Ignition system DODGE RAM 1999 Service Owner's Guide

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1st gear and read governor pressure voltage. If voltage is one volt or
greater, replace PCM. If voltage is less than one volt, test is
complete.
15) Drain transmission fluid and remove oil pan. Disconnect
governor pressure solenoid harness connector. Inspect connector and
terminals for damage. Repair as necessary. If connector and terminals
are okay, measure resistance across governor pressure solenoid
terminals. If resistance is 2.5 ohms or less, go to next step. If
resistance is greater than 2.5 ohms, go to step 17).
16) Replace governor pressure solenoid. Replace oil pan and
fill with fluid. Reconnect all disconnected harness connectors. Using
scan tool, perform GOV and 3-4 SHIFT VALVE SYSTEM TEST. Select 1st
gear and read governor pressure voltage. If voltage is one volt or
greater, replace PCM. If voltage is less than one volt, test is
complete.
17) Repair or replace transmission solenoid and harness
assembly. Reconnect all disconnected harness connectors. Using scan
tool, perform GOV and 3-4 SHIFT VALVE SYSTEM TEST. Select 1st gear and
read governor pressure voltage. If voltage is one volt or greater,
replace PCM. If voltage is less than one volt, test is complete.
18) Remove transmission control relay. Inspect transmission
control relay connector and terminals for damage. Repair as necessary.
If connector and terminals are okay, turn ignition on. Measure voltage
between ground and fused B+ circuit at transmission control relay
connector. If voltage is 10 volts or less, repair open fused B+
circuit. If voltage is greater than 10 volts, go to next step.
19) Turn ignition off. Measure resistance of transmission
control relay output circuit at transmission control relay connector
and TCC solenoid harness connector. If resistance is greater than 5
ohms, repair open transmission control relay output circuit. If
resistance is 5 ohms or less, go to next step.
20) Measure resistance between ground and transmission
control relay output circuit at transmission solenoid harness
connector. If resistance is less than 5 ohms, repair open in
transmission control relay output circuit. If resistance is 5 ohms or
greater, replace transmission control relay.
Diagnostic Procedure (AB, BR & WJ Bodies)
NOTE: On WJ body, if all solenoid codes, P0743, P0748 and P0753 are
set, go to test DTC P1765: TRANS 12-VOLT SUPPLY RELAY CNTRL
CIRCUIT before proceeding.
1) Using scan tool, read DTCs. On BR and WJ bodies, go to
next step. On AB body, if DTC SPECIFIC GOOD TRIPS counter is not
displayed or displayed count is not "0", go to step 20). If DTC
SPECIFIC GOOD TRIPS counter is displayed and displayed count is "0",
indicating DTC still exists, go to next step.
2) If DTC P1765 is also set, go to DTC DTC P1765: TRANS 12-
VOLT SUPPLY RELAY CNTRL CIRCUIT. If DTC P1765 is not set, go to next
step.
3) Using scan tool, perform GOV and 3-4 SHIFT VALVE SYSTEM
TEST. Select 1st gear and read governor pressure voltage. If voltage
is one volt or greater, go to step 20). If voltage is less than one
volt, go to next step.
4) Turn ignition off. Disconnect transmission solenoid
harness connector. Turn ignition on. Using scan tool, actuate
transmission control relay. Measure voltage between ground and
transmission relay output circuit at transmission solenoid harness
connector. If voltage does not switch from zero to greater than 10
volts, go to step 17). If voltage switches from zero to greater than
10 volts, go to next step.
5) Turn ignition off. Disconnect PCM harness connectors.

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Inspect connectors and terminals for damage. Repair as necessary. If
connectors and terminals are okay, turn ignition on. Measure voltage
between ground and governor pressure solenoid control circuit at
transmission solenoid harness connector. If voltage is greater than 10
volts, go to next step. If voltage is 10 volts or less, go to step 7).
6) Repair governor pressure solenoid control circuit for
short to voltage. Reconnect all disconnected harness connectors. Using
scan tool, perform GOV and 3-4 SHIFT VALVE SYSTEM TEST. Select 1st
gear and read governor pressure voltage. If voltage is one volt or
greater, replace PCM. If voltage is less than one volt, test is
complete.
7) Turn ignition off. Reconnect transmission solenoid harness
connector. Measure resistance between ground and governor pressure
solenoid control circuit at White PCM harness connector C2. If
resistance is 5 ohms or less, repair short to ground in governor
pressure solenoid control circuit. If resistance is greater than 5
ohms, go to next step.
8) Remove transmission control relay. Inspect transmission
control relay connector and terminals for damage. Repair as necessary.
If connector and terminals are okay, measure resistance between
transmission control relay output circuit at transmission control
relay connector and governor pressure solenoid control circuit at
White PCM harness connector C2. If resistance is 2.5-5.0 ohms, replace
PCM. If resistance is not 2.5-5.0 ohms, go to next step.
9) Measure resistance between transmission control relay
output circuit at transmission control relay connector and governor
pressure solenoid control circuit at White PCM harness connector C2.
If resistance is greater than 5 ohms, go to next step. If resistance
is 5 ohms or less, go to step 12).
10) Drain transmission fluid and remove oil pan. Disconnect
governor pressure solenoid harness connector. Inspect connector and
terminals for damage. Repair as necessary. If connector and terminals
are okay, measure resistance across governor pressure solenoid
terminals. If resistance is 5 ohms or less, repair or replace
transmission solenoid and harness assembly. If resistance is greater
than 5 ohms, go to next step.
11) Measure resistance of governor pressure solenoid control
circuit between White PCM harness connector C2 and transmission
solenoid harness connector. If resistance is greater than 5 ohms,
repair open governor pressure solenoid control circuit. If resistance
is 5 ohms or less, replace governor pressure solenoid.
12) Measure resistance between governor pressure solenoid
control circuit and all other circuits at transmission solenoid
harness connector. If resistance is less than 2.5 ohms between any 2
circuits, go to next step. If resistance is not less than 2.5 ohms
between any 2 circuits, go to step 14).
13) Repair governor pressure solenoid control circuits that
were shorted together. Reconnect all disconnected harness connectors.
Using scan tool, perform GOV and 3-4 SHIFT VALVE SYSTEM TEST. Select
1st gear and read governor pressure voltage. If voltage is one volt or
greater, replace PCM. If voltage is less than one volt, test is
complete.
14) Drain transmission fluid and remove oil pan. Disconnect
governor pressure solenoid harness connector. Inspect connector and
terminals for damage. Repair as necessary. If connector and terminals
are okay, measure resistance across governor pressure solenoid
terminals. If resistance is 2.5 ohms or less, go to next step. If
resistance is greater than 2.5 ohms, go to step 16).
15) Replace governor pressure solenoid. Replace oil pan and
fill with fluid. Reconnect all disconnected harness connectors. Using
scan tool, perform GOV and 3-4 SHIFT VALVE SYSTEM TEST. Select 1st
gear and read governor pressure voltage. If voltage is one volt or
greater, replace PCM. If voltage is less than one volt, test is

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complete.
16) Repair or replace transmission solenoid and harness
assembly. Reconnect all disconnected harness connectors. Using scan
tool, perform GOV and 3-4 SHIFT VALVE SYSTEM TEST. Select 1st gear and
read governor pressure voltage. If voltage is one volt or greater,
replace PCM. If voltage is less than one volt, test is complete.
17) Remove transmission control relay. Inspect transmission
control relay connector and terminals for damage. Repair as necessary.
If connector and terminals are okay, turn ignition on. Measure voltage
between ground and fused B+ circuit at transmission control relay
connector. If voltage is 10 volts or less, repair open fused B+
circuit. If voltage is greater than 10 volts, go to next step.
18) Turn ignition off. Measure resistance of transmission
control relay output circuit at transmission control relay connector
and TCC solenoid harness connector. If resistance is greater than 5
ohms, repair open transmission control relay output circuit. If
resistance is 5 ohms or less, go to next step.
19) Measure resistance between ground and transmission
control relay output circuit at transmission solenoid harness
connector. If resistance is less than 5 ohms, repair short to ground
in transmission control relay output circuit. If resistance is 5 ohms
or greater, replace transmission control relay.
20) Using scan tool, erase DTCs. Start engine. Using scan
tool, read DTCs while wiggling wiring harness between governor
pressure solenoid and PCM. Note if DTC P0748 resets. If DTC P0748
resets, repair wiring harness as necessary. If DTC P0748 does not
reset, go to next step.
21) Inspect all related wiring and connectors. Repair as
necessary. If wiring and connectors are okay, see INACTIVE DTC
CONDITION under SELF-DIAGNOSTIC SYSTEM. Testing is complete.
DTC P0751: O/D SWITCH PRESSED (LO) MORE THAN 5 MIN
Circuit Description
Circuit is monitored after engine is running for 10 seconds
and reviewed every 440ms. Code sets if overdrive switch is held low
for 5 minutes or more from time of closure or ignition on.
Possible Causes
* Fused B+ circuit open.
* Solenoid and harness assembly defective.
* Governor pressure solenoid out of tolerance.
* Transmission control relay defective.
* Governor pressure solenoid control circuit shorted to
ground.
* Governor pressure solenoid harness defective.
* Governor pressure solenoid control circuit open.
* Transmission control relay output circuit open.
* Transmission control relay output circuit shorted to
ground.
* PCM defective.
Diagnostic Procedure
1) Turn ignition off. Disconnect PCM harness connectors.
Inspect connectors and terminals for damage. Repair as necessary. If
connectors and terminals are okay, measure resistance between ground
and Overdrive (O/D) off switch sense circuit at Gray PCM harness
connector C3. If resistance is less than 5 ohms, go to next step. If
resistance is 5 ohms or greater, go to step 3).
2) Disconnect O/D switch harness connector. Inspect connector
and terminals for damage. Repair as necessary. If connector and
terminals are okay, measure resistance between ground and O/D off

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switch sense circuit at O/D switch harness connector. If resistance is
less than 5 ohms, repair short to ground in O/D switch sense circuit.
If resistance is 5 ohms or greater, replace O/D off switch.
3) Conditions required to set DTC P0751 are not present at
this time. DTC P0751 sets if PCM senses O/D off switch input is held
low for 5 minutes or from time of closure or ignition on. Possible
causes are: faulty O/D OFF switch, shorted wire or faulty PCM. Inspect
all related wiring and connectors. Repair as necessary. If wiring and
connectors are okay, see INACTIVE DTC CONDITION under SELF-DIAGNOSTIC
SYSTEM. Testing is complete.
DTC P0753: TRANS 3-4 SHIFT SOLENOID/TRANS RELAY CIRCUITS
Circuit Description
Circuit is monitored continuously while key is on. Code sets
if voltage detected on 3-4 shift solenoid control circuit at the
Powertrain Control Module (PCM) does not match expected voltage.
Possible Causes
* Transmission mechanically defective.
* TPS codes set.
* Transmission 3-4 solenoid wiring harness defective.
* Transmission fluid burnt or oil pan has excessive debris.
* Shift control solenoid circuit shorted to ground.
* Solenoid and harness assembly defective.
* Transmission control relay output circuit open.
* Transmission control relay output circuit shorted to
ground.
* PCM defective.
Diagnostic Procedure (AN & DN Bodies)
1) If DTC P1765 is also set, go to DTC P1765: TRANS 12-VOLT
SUPPLY RELAY CNTRL CIRCUIT. If DTC P1765 is not set, go to next step.
2) Road test vehicle and reach a speed of 50 MPH. Depress
Overdrive (OD) switch 4 times so vehicle attempts to shift from 4th
gear to 3rd gear and back. If vehicle does not shift between 3rd and
4th gear, go to step 5). If vehicle shifts between 3rd and 4th gear,
go to next step.
3) Using scan tool, erase DTCs. Start engine. Using scan
tool, read DTCs while wiggling wiring harness between 3-4 shift
solenoid and PCM. If DTC P0753 resets, repair wiring harness as
necessary. If DTC P0753 does not reset, go to next step.
4) Using wiring diagram as a guide, inspect wiring and
connectors. Repair wiring harness as necessary. If wiring and
connectors are okay, see INACTIVE DTC CONDITION under SELF-DIAGNOSTIC
SYSTEM. Testing is complete.
5) Turn ignition off. Disconnect transmission solenoid
harness connector. Turn ignition on. Using scan tool, actuate
transmission control relay. Measure voltage between ground and
transmission relay output circuit at transmission solenoid harness
connector. If voltage does not switch from zero to greater than 10
volts, go to step 16). If voltage switches from zero to greater than
10 volts, go to next step.
6) Turn ignition off. Disconnect PCM harness connectors.
Inspect connectors and terminals for damage. Repair as necessary. If
connectors and terminals are okay, turn ignition on. Measure voltage
between ground and 3-4 shift solenoid control circuit at transmission
solenoid harness connector. If voltage is greater than 10 volts, go to
next step. If voltage is 10 volts or less, go to step 8).
7) Repair 3-4 shift solenoid control circuit for short to
voltage. Reconnect all disconnected harness connectors. Road test
vehicle and reach a speed of 50 MPH. Depress Overdrive (OD) switch 4

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connector. If resistance is 5 ohms or greater, repair open 3-4 shift
solenoid circuit. If resistance is less than 5 ohms, replace
transmission solenoid and harness assembly.
12) Measure resistance between transmission control relay
output circuit at transmission control relay connector and 3-4 shift
solenoid control circuit at White PCM harness connector C2. If
resistance is 26-40 ohms, replace PCM. If resistance is not 26-40
ohms, test is complete.
13) Remove transmission control relay. Inspect transmission
control relay connector and terminals for damage. Repair as necessary.
If connector and terminals are okay, turn ignition on. Measure voltage
between ground and fused B+ circuit at transmission control relay
connector. If voltage is 10 volts or less, repair open fused B+
circuit. If voltage is greater than 10 volts, go to next step.
14) Turn ignition off. Measure resistance of transmission
control relay output circuit at transmission control relay connector
and TCC solenoid harness connector. If resistance is greater than 5
ohms, repair open transmission control relay output circuit. If
resistance is 5 ohms or less, go to next step.
15) Measure resistance between ground and transmission
control relay output circuit at transmission solenoid harness
connector. If resistance is less than 5 ohms, repair short to ground
in transmission control relay output circuit. If resistance is 5 ohms
or greater, replace transmission control relay.
16) Using scan tool, erase DTCs. Start engine. Attempt to
duplicate data and reset code. Using wiring diagram as a guide,
inspect wiring and connectors. Repair wiring harness as necessary. If
wiring and connectors are okay, go to next step.
17) Wiggle wiring harness between TCC solenoid and PCM. Note
if DTC P0753 resets. If DTC P0753 resets, repair wiring harness as
necessary. If DTC P0753 does not reset, replace PCM and see INACTIVE
DTC CONDITION under SELF-DIAGNOSTIC SYSTEM. Testing is complete.
Diagnostic Procedure (WJ Body)
NOTE: If all solenoid codes, P0743, P0748 and P0753 are set, go to
test DTC P1765: TRANS 12-VOLT SUPPLY RELAY CNTRL CIRCUIT
before proceeding.
1) Using scan tool, read DTCs. If DTC SPECIFIC GOOD TRIPS
counter is not displayed or displayed count is not "0", go to next
step. If DTC SPECIFIC GOOD TRIPS counter is displayed and displayed
count is "0", go to step 16).
2) Road test vehicle and reach a speed of 50 MPH. Depress
Overdrive (OD) switch 4 times so that vehicle attempts to shift from
4th gear to 3rd gear and back. If vehicle does not shift between 3rd
and 4th gear, go to step 4). If vehicle shifts between 3rd and 4th
gear, go to next step.
3) Record freeze frame data to determine conditions when code
was set. Using wiring diagram as a guide, inspect wiring and
connectors. Repair wiring harness as necessary. If wiring and
connectors are okay, see INACTIVE DTC CONDITION under SELF-DIAGNOSTIC
SYSTEM. Testing is complete.
4) Turn ignition off. Disconnect transmission solenoid
harness connector. Inspect connector and terminals for damage. Repair
as necessary. If connector and terminals are okay, turn ignition on.
Using scan tool, actuate transmission control relay. Measure voltage
between ground and transmission relay output circuit at transmission
solenoid harness connector. If voltage does not switch from zero to
greater than 10 volts, go to step 12). If voltage switches from zero
to greater than 10 volts, go to next step.
5) Turn ignition off. Disconnect PCM harness connectors.
Inspect connectors and terminals for damage. Repair as necessary. If

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(1) - See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.\
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3) Ensure fuel tank is at least 1/4 full. If fuel level is
too low, correct fuel level and retest. If fuel level is okay, go to
next step.
4) Ensure transfer case is not in low range. Shift transfer
case out of low range. If transfer case is not in low range, go to
next step.
5) Ensure PTO is not engaged. Disengage PTO. If PTO is not
engaged, go to next step.
6) Ensure transmission fluid temperature is above 32
F (0C).
Warm transmission to normal operating temperature. If transmission
fluid temperature is above 32
F (0C), go to next step.
7) Turn ignition on. Using scan tool, build a custom display
with engine RPM, output shaft SPD, TCC solenoid, O/D solenoid and
throttle position. Set overdrive to off position. Road test vehicle
and reach a steady speed of 55 MPH with a minimum throttle opening
voltage of 1.15 volts for 20 seconds. Note shift patterns while
vehicle is attaining speed. If engine RPM is within 60 RPM of output
shaft speed RPM, go to next step. If engine RPM is not within 60 RPM
of output shaft speed RPM, go to step 15).
8) If output shaft speed RPM is greater than engine RPM, go
to next step. If output shaft speed RPM is equal to or less than
engine RPM, go to step 15).
9) Road test vehicle and reach a steady speed of 55 MPH and
engage overdrive. If engine RPM is 69 percent of output shaft speed,
go to step 15). If engine RPM is not 69 percent of output shaft speed,
go to next step.
10) Connect a 0-300 psi (0-21 kg/cm
) pressure gauge to
transmission Overdrive (O/D) clutch pressure test port. Connect a
second 0-300 psi (0-21 kg/cm
) pressure gauge to transmission governor
pressure test port. See appropriate AUTOMATIC TRANSMISSION OVERHAUL
article. Ensure engine and transmission are at normal operating
temperature. With an assistant, test drive vehicle. Using scan tool,
select GOV and 3-4 SHIFT VALVE SYSTEM TEST. Select 4th gear while
monitoring pressure gauge. Governor pressure should rise to greater
than 20 psi (1.4 kg/cm
) and O/D pressure should rise to greater than
40 psi (2.8 kg/cm). If pressures are as specified, go to next step.
If pressures are not as specified, go to step 13).
11) Check transmission fluid for proper level and for any
debris. Fill or repair transmission as necessary. If fluid level and
condition are okay, go to next step.
12) Drain transmission fluid and remove oil pan. If
transmission fluid is burnt or has excessive debris, repair as
necessary. If transmission fluid is okay, go to step 23).
13) Check transmission fluid for proper level and for any
debris. Fill or repair transmission as necessary. If fluid level and
condition are okay, go to next step.
14) Leave gauges connected. Replace 3-4 shift solenoid. Start
engine and allow engine and transmission to reach normal operating
temperature. Using scan tool, select GOV and 3-4 SHIFT VALVE SYSTEM
TEST. Select 4th gear while monitoring pressure gauges. Governor
pressure should rise to greater than 20 psi (1.4 kg/cm
) and O/D
pressure should rise to greater than 40 psi (2.8 kg/cm). If pressures
are as specified, testing is complete. If pressures are not as
specified, see appropriate AUTOMATIC TRANSMISSION OVERHAUL article,
paying attention to seals and clutches related to O/D clutch.
15) Check transmission fluid for proper level and for any
debris. Fill or repair transmission as necessary. If fluid level and
condition are okay, go to next step.
16) Start engine. Using scan tool, perform TCC SYSTEM TEST.

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If engine stalls, go to next step. If engine does not stall, go to
step 19).
17) Using scan tool, select GOV and 3-4 SHIFT VALVE SYSTEM
TEST. Select 4th gear. If engine stalls, go to next step. If engine
does not stall, go to step 23).
18) Replace TCC solenoid. Perform GOV and 3-4 SHIFT VALVE
SYSTEM TEST. Select 4th gear. If engine stalls, repair internal
problem. Check for internally blocked passages. See appropriate
AUTOMATIC TRANSMISSION OVERHAUL article. If engine does not stall,
test is complete.
19) Turn ignition off. Remove oil pump. Inspect reaction
shaft, input shaft and input seal. If any parts are damaged, repair as
necessary and go to next step. If all parts are okay, replace torque
converter.
20) Start engine. Perform GOV and 3-4 SHIFT VALVE SYSTEM
TEST. Select 4th gear. If engine stalls, go to next step. If engine
does not stall, go to step 23).
21) Turn ignition off. Replace TCC solenoid. Start engine.
Perform GOV and 3-4 SHIFT VALVE SYSTEM TEST. Select 4th gear. If
engine stalls, repair internal problem. Check for internally blocked
passages. See appropriate AUTOMATIC TRANSMISSION OVERHAUL article. If
engine does not stall, go to next step.
22) Turn ignition off. Remove oil pump. Inspect reaction
shaft, input shaft and input seal. If any parts are damaged, repair as
necessary and replace torque converter. If all parts are okay, test is
complete.
23) Turn ignition off. Remove oil pump. Inspect reaction
shaft, input shaft and input seal. If any parts are damaged, repair as
necessary and replace torque converter. If all parts are okay, go to
next step.
24) Record freeze frame data to determine conditions when
code was set. Using wiring diagram as a guide, inspect wiring and
connectors. Repair wiring harness as necessary. If wiring and
connectors are okay, go to next step.
25) Using scan tool, erase DTCs. Start engine. Attempt to
duplicate data and reset code. Road test vehicle maintaining a
constant throttle opening voltage of 1.15 volts, reach a speed of 60
MPH. Repeat road test 4 times. Note if DTC P1740 resets. If DTC P1740
resets, there are no other possible causes remaining. Problem is
considered to be an intermittent problem in wiring harness connector
or wire. See INACTIVE DTC CONDITION under SELF-DIAGNOSTIC SYSTEM.
Repair wiring harness as necessary. If DTC P1740 does not reset,
testing is complete.
DTC P1756: GOV PRESS NOT EQUAL TO TARGET @ 15-20 PSI
Circuit Description
Circuit is monitored continuously while key is on and engine
running, not in Park or Neutral position or with Malfunction Indicator
Light (MIL) illuminated. Code sets if governor pressure sensor output
is not 15-30 psi (1.0-2.1 kg/cm
) when requested pressure is 20-25 psi
(1.4-1.7 kg/cm) for 2.2 seconds. Test must fail 5 times to set code.
Possible Causes
* Other transmission codes are set.
* Solenoid pack connector 5 volt supply circuit open.
* Governor pressure sensor defective.
* Transmission fluid burnt or oil pan has excessive debris.
* Governor pressure out of range.
* Transmission leaking internally.
Diagnostic Procedures

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as necessary. If connector and terminals are okay, turn ignition on.
Measure voltage between ground and 5-volt supply circuit at
transmission solenoid harness connector. If voltage is 4.5 volts or
less, repair open 5-volt supply circuit. If voltage is greater than 4.
5 volts, replace governor pressure sensor.
13) Turn engine off. Install transmission control relay.
Drain transmission fluid and remove oil pan. Inspect pan for burnt oil
and debris. Repair transmission as necessary. See appropriate
AUTOMATIC TRANSMISSION OVERHAUL article. If transmission is okay, go
to next step.
14) Replace governor pressure solenoid. Replace transmission
oil pan and refill fluid. Start engine. Remove transmission control
relay. Depress brake pedal and place gear selector in "D" position.
Read gauge pressure. If pressure is 40-55 psi (2.8-3.9 kg/cm
),
testing is complete. If pressure is not as specified, replace valve
body.
15) Conditions required to set DTC P1756 are not present at
this time. Using scan tool, clear DTCs. Start engine and check for
DTCs. Wiggle wiring harness between governor pressure sensor and PCM.
Note if DTC P1756 resets. If DTC P1756 resets, repair wiring harness
as necessary. If DTC P1756 does not reset, see INACTIVE DTC CONDITION
under SELF-DIAGNOSTIC SYSTEM. Testing is complete.
DTC P1757: GOV PRES ABOVE 3 PSI IN GEAR WITH 0 MPH
Circuit Description
Circuit is monitored continuously while key is on and engine
running, not in Park or Neutral position or with Malfunction Indicator
Light (MIL) illuminated. Code sets if governor pressure sensor is
greater than 3 psi (.2 kg/cm
) when requested pressure is zero with
governor pressure solenoid duty cycle at 95 percent for 2.65 seconds.
Test must fail twice to set code.
Possible Causes
* Other transmission codes are set.
* Solenoid pack connector 5-volt supply circuit open.
* Governor pressure sensor defective.
* Wiring harness and/or connectors defective.
* Transmission fluid burnt or oil pan has excessive debris.
* Valve body defective.
Diagnostic Procedures
1) Using scan tool, read DTCs. On AN and DN bodies, go to
next step. On all except AN and DN bodies, if DTC SPECIFIC GOOD TRIPS
counter is not displayed or displayed count is not "0", go to step 8).
If DTC SPECIFIC GOOD TRIPS counter is displayed and displayed count is
"0", go to next step.
2) Repair any other transmission related DTCs before
proceeding. If no other transmission related DTCs exist, go to next
step.
3) Start engine. Allow engine to reach normal operating
temperature. Set parking brake, depress brake pedal and place gear
selector in "D" position. Using scan tool, read governor pressure
sensor value. If value is greater than 3 psi (.2 kg/cm
), go to next
step. If value is 3 psi (.2 kg/cm) or less, go to step 8).
4) Turn ignition off. Install a pressure gauge at governor
pressure test port. See TESTING in appropriate AUTOMATIC TRANSMISSION
OVERHAUL article. Start engine. With gear selector in "D" position,
read gauge pressure. If pressure is less than 3 psi (.2 kg/cm
), go to
step 7). If pressure is 3 psi (.2 kg/cm) or greater, go to next step.
5) Turn engine off. Drain transmission fluid and remove oil
pan. Inspect oil pan for burnt oil and debris. Repair transmission as

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DIAGNOSTIC SYSTEM. Testing is complete.
15) Turn ignition off. Disconnect transmission solenoid
harness connector. Disconnect PCM harness connectors. Inspect
connectors and terminals for damage. Repair as necessary. If connector
and terminals are okay, measure resistance of governor pressure sensor
ground circuit between transmission solenoid harness connector and
Black PCM harness connector C1. If resistance is greater than 5 ohms,
repair open governor pressure sensor ground circuit. If resistance is
5 ohms or less, go to next step.
16) Turn ignition on. Measure voltage between ground and
governor pressure signal circuit at White PCM harness connector C2. If
voltage is greater than one volt, repair governor pressure signal
circuit for short to voltage. If voltage is one volt or less, go to
next step.
17) Turn ignition off. Measure resistance of governor
pressure sensor signal circuit between White PCM harness connector C2
and governor pressure sensor harness connector. If resistance is
greater than 5 ohms, repair open in governor pressure sensor signal
circuit. If resistance is 5 ohms or less, go to next step.
18) Reconnect all harness connectors except White PCM harness
connector C2. Turn ignition on. Using scan tool, read governor
pressure sensor voltage. If voltage is greater than 4.65 volts, go to
next step. If voltage is 4.65 volts or less, replace PCM.
19) Turn ignition off. Disconnect all PCM connectors. Drain
transmission fluid and remove oil pan. Disconnect pressure/temperature
sensor connector. Inspect connectors and terminals for damage. Repair
as necessary. If connector and terminals are okay, measure resistance
of governor pressure sensor signal circuit between White PCM harness
connector C2 and governor pressure sensor connector. If resistance is
greater than 5 ohms, repair or replace transmission solenoid and
harness assembly. If resistance is 5 ohms or less, go to next step.
20) Measure resistance of governor pressure sensor ground
circuit between Black PCM harness connector C1 and governor pressure
sensor harness connector. If resistance is greater than 5 ohms, repair
or replace transmission solenoid and harness assembly. If resistance
is 5 ohms or less, go to next step.
21) Turn ignition on. Measure voltage between ground and
governor pressure signal circuit at White PCM harness connector C2. If
voltage is greater than one volt, repair or replace transmission
solenoid and harness assembly. If voltage is one volt or less, replace
pressure/temperature sensor.
22) Conditions required to set DTC P1763 are not present at
this time. DTC P1763 sets if governor pressure sensor input is greater
than 4.89 volts for 8.5 seconds. Possible causes are: faulty PCM,
faulty governor pressure sensor, dirty or corroded connectors or open
or shorted wiring. Inspect all related wiring and connectors. Repair
as necessary. If wiring and connectors are okay, sing scan tool to
monitor governor pressure voltage. Wiggle wiring harness between
governor pressure sensor and PCM. If voltage fluctuates, repair wiring
harness as necessary. If voltage does not fluctuate, see INACTIVE DTC
CONDITION under SELF-DIAGNOSTIC SYSTEM. Testing is complete.
DTC P1763B: GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH (AN & DN
BODIES)
Circuit Description
Circuit is monitored continuously while key is on and engine
running. Code sets if governor pressure is greater than 4.89 volts for
8.5 seconds.
Possible Causes
* Transmission harness/solenoid defective.

Page 262 of 1691

10) If governor pressure voltage is than .12-.80 volt, go to
next step. If governor pressure voltage is .80 volt or greater, go to
test DTC P1763B: GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH (AN & DN
BODIES).
11) Wiggle wiring harness between PCM and governor pressure
sensor while monitoring governor pressure voltage on scan tool. If
voltage changes while wiggling wiring harness, repair wiring harness
as necessary. If voltage does not change, conditions required to set
DTC P1764 are not present at this time. DTC P1764 sets if governor
pressure sensor input is less than .1 volt for 8.5 seconds. Possible
causes are: PCM internally shorted or open, incorrectly wired, dirty
or corroded connectors or open or shorted wiring. See INACTIVE DTC
CONDITION under SELF-DIAGNOSTIC SYSTEM. Testing is complete.
Diagnostic Procedures (BR Body)
1) Using scan tool, read DTCs. If DTC SPECIFIC GOOD TRIPS
counter is not displayed or displayed count is not "0", go to step
23). If DTC SPECIFIC GOOD TRIPS counter is displayed and displayed
count is "0", go to next step.
2) Turn ignition off. Disconnect transmission solenoid
harness connector. Inspect connector and terminals for damage. Repair
as necessary. If connector and terminals are okay, turn ignition on.
Measure voltage between ground and 5-volt supply circuit at
transmission solenoid harness connector. If voltage is 4.5-5.5 volts,
go to next step. If voltage is not as specified, repair open 5-volt
supply circuit.
3) Reconnect transmission solenoid harness connector. Using
scan tool, read governor pressure sensor voltage. If voltage is
greater than 4.65 volts, go to step 9). If voltage is less than .12
volt, go to next step. If voltage is not .12-.80 volt, go to step 23).
If voltage is .80-4.65 volts, go to step 16).
4) Check and record freeze frame data to determine conditions
which set code. Turn ignition off. Disconnect PCM harness connectors.
Disconnect transmission solenoid harness connector. Inspect connector
and terminals for damage. Repair as necessary. If connector and
terminals are okay, measure resistance between sensor ground circuit
at Black PCM harness connector C1 and governor pressure sensor signal
circuit at White PCM harness connector C2. If resistance is less than
5 ohms, repair governor pressure sensor signal circuit for short to
ground circuit. If resistance is 5 ohms or greater, go to next step.
5) Measure resistance between ground and governor pressure
sensor signal circuit at White PCM harness connector C2. If resistance
is less than 5 ohms, repair governor pressure sensor signal circuit
for short to ground. If resistance is 5 ohms or greater, go to next
step.
6) Drain transmission fluid and remove oil pan. Disconnect
pressure/temperature sensor harness connector. Inspect connector and
terminals for damage. Repair as necessary. If connector and terminals
are okay, reconnect transmission solenoid harness connector. Measure
resistance between ground circuit and governor pressure sensor signal
circuit at governor pressure sensor harness connector. If resistance
is less than 5 ohms, repair or replace transmission solenoid and
harness assembly. If resistance is 5 ohms or greater, go to next step.
7) Measure resistance between ground and governor pressure
sensor signal circuit at governor pressure sensor harness connector.
If resistance is less than 5 ohms, repair or replace transmission
solenoid and harness assembly. If resistance is 5 ohms or greater, go
to next step.
8) Reconnect all harness connectors except
pressure/temperature sensor harness connector. Turn ignition on. Using
scan tool, read governor pressure sensor voltage. If voltage is 4.8
volts or less, replace PCM. If voltage is greater than 4.8 volts,
replace pressure/temperature sensor.

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