key DODGE RAM 1999 Service Owner's Manual
[x] Cancel search | Manufacturer: DODGE, Model Year: 1999, Model line: RAM, Model: DODGE RAM 1999Pages: 1691, PDF Size: 40.34 MB
Page 235 of 1691
problem is found, measure resistance between output speed sensor
terminals. If resistance is 300-1200 ohms, go to next step. If
resistance is not as specified, replace output speed sensor.
7) Reconnect output speed sensor. Measure resistance between
ground and output speed sensor ground circuit at PCM harness
connector. If resistance is greater than 5 ohms, go to next step. If
resistance is not as specified, repair output speed sensor ground
circuit for a short to ground.
8) Measure resistance between ground and output speed sensor
signal circuit at PCM harness connector. If resistance is less than 5
ohms, repair output speed sensor signal circuit for a short to ground.
If resistance is not as specified, go to next step.
9) Measure resistance between output speed sensor signal
circuit and ground circuit at PCM harness connector. If resistance is
300-1200 ohms, replace PCM. If resistance is not as specified, go to
next step.
10) Disconnect output speed sensor harness connector. Measure
resistance of output speed sensor signal circuit between output speed
sensor harness connector and PCM harness connector. If resistance is
greater than 5 ohms, repair open in output speed sensor signal
circuit. If resistance is not as specified, repair open in output
speed sensor ground circuit.
11) Turn ignition on. Measure voltage between ground and
speed sensor ground circuit at PCM harness connector. Place gearshift
lever in each gear position and record voltage at each position. If
voltage is greater than one volt in any gear position, repair speed
sensor ground circuit for a short to power. If voltage is not as
specified, go to next step.
12) Raise and support vehicle. Start engine. Place gearshift
lever in "OD" position. Release brakes and allow wheels to rotate.
Using scan tool, monitor output speed sensor. While monitoring output
speed sensor, wiggle harness between output speed sensor and PCM. If
reading dropped towards zero while wiggling harness, repair
intermittent short or open in harness. If reading does not drop
towards zero while wiggling harness, problem is intermittent. See
INACTIVE DTC CONDITION under SELF-DIAGNOSTIC SYSTEM. Testing is
complete.
DTC P0740: TORQ CONV CLU, NO RPM DROP AT LOCKUP
Circuit Description
Circuit is monitored continuously while key is on, and gear
selector is not in Park or Neutral. Code sets if Torque Converter
Clutch (TCC) does not achieve desired drop in RPM when TCC solenoid is\
near maximum duty cycle. A bad test 3 consecutive times is required to
set code.
Possible Causes
* Misfire trouble code set.
* Vehicle stalls (faulty TCC solenoid).
* TCC shaft seal/seal defective.
* Transmission fluid contaminated.
* TCC solenoid wiring harness defective.
* TCC defective.
* TCC hydraulic circuit damaged.
Diagnostic Procedure
1) Using scan tool, read DTCs. On all bodies except AB and WJ
bodies, go to next step. On AB and WJ bodies, if DTC SPECIFIC GOOD
TRIPS counter is not displayed or displayed count is not "0", go to
step 10). If DTC SPECIFIC GOOD TRIPS counter is displayed and
displayed count is "0", indicating DTC still exists, go to next step.
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![DODGE RAM 1999 Service Owners Manual 2) If any DTCs listed are present, perform appropriate
test(s). See TORQUE CONVERTOR CLUTCH (TCC) TESTS table. If no DTCs a\
re
present, go to next step.
TORQUE CONVERTOR CLUTCH (TCC) TESTS](/img/12/56915/w960_56915-235.png "DODGE RAM 1999 Service Owners Manual 2) If any DTCs listed are present, perform appropriate
test(s). See TORQUE CONVERTOR CLUTCH (TCC) TESTS table. If no DTCs a\
re
present, go to next step.
TORQUE CONVERTOR CLUTCH (TCC) TESTS")
2) If any DTCs listed are present, perform appropriate
test(s). See TORQUE CONVERTOR CLUTCH (TCC) TESTS table. If no DTCs a\
re
present, go to next step.
TORQUE CONVERTOR CLUTCH (TCC) TESTS
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DTC DTC Message
P0122 (1) ................. THROTTLE POSITION SENSOR VOLTAGE TOO LOW
P0123 ( 1) ................ THROTTLE POSITION SENSOR VOLTAGE TOO HIGH
P1696 ( 1) .......................... PCM FAILURE EEPROM WRITE DENIED
P0743 ........ TORQUE CONVERTOR CLUTCH SOLENOID/TRANS RELAY CIRCUITS
( 2) ........................................................ MISFIRE
P0320 ( 1) ......................... NO CRANK REFERENCE SIGNAL AT PCM
( 1) - See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
( 2) - Perform appropriate misfire DTC test. See appropriate
SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
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3) 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.
4) Start engine. Using scan tool, perform TCC SYSTEM TEST. If
vehicle does not stall, go to step 9). If vehicle stalls, go to next
step.
5) Using scan tool, perform GOV and 3-4 SHIFT VALVE SYSTEM
TEST. Select 4th gear. If vehicle stalls, go to next step. If vehicle
does not stall, go to step 7).
6) Turn ignition off. Replace TCC solenoid. Using scan tool,
perform GOV and 3-4 SHIFT VALVE SYSTEM TEST. Select 4th gear. If
vehicle stalls, problem in internal. Check for blocked passage. If
vehicle does not stall, testing is complete.
7) Turn ignition off. Remove oil pump and inspect reaction
shaft, input shaft and input seal. Repair transmission as necessary.
See appropriate AUTOMATIC TRANSMISSION OVERHAUL article. If
transmission is okay, go to next step.
8) 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.
9) Turn ignition off. Connect a pressure gauge to
transmission cooler OUT port. Start engine. Using scan tool, perform
TCC SYSTEM TEST. If pressure increases when TCC is actuated, go to
next step. If pressure does not increase, repair leaks or blockage in
hydraulic circuit, or repair valve body as necessary.
10) Turn engine off. Remove oil pump and inspect reaction
shaft, input shaft and input seal. Repair transmission as necessary.
See appropriate AUTOMATIC TRANSMISSION OVERHAUL article. If
transmission is okay, there are no other potential causes remaining.
TCC is assumed to be defective. Replace torque converter.
DTC P0743: TORQUE CONV CLUTCH SOLENOID/TRANS RELAY CKT
NOTE: To test transmission temperature sensor, engine and
transmission temperature must be less than 85F (29C).
Circuit Description
Circuit is monitored continuously while key is on. Code sets
if voltage detected on Torque Converter Clutch (TCC) at the Powertrain\
Control Module (PCM) does not match desired voltage.
Possible Causes
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15) Remove transmission control relay. Inspect connector and
terminals for damage. Repair as necessary. If connector and terminals
are okay, measure resistance of transmission control relay output
circuit between ground and transmission control relay 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, go to next step.
16) Measure resistance of transmission control relay output
circuit between 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.
17) Turn ignition on. Measure voltage between ground and B+
circuit at transmission control relay harness connector. If voltage is
10 volts or less, repair open fused B+ circuit. If resistance is
greater than 10 volts, replace transmission control relay.
18) Record freeze frame data to determine conditions when
code was set. Using freeze frame data and wiring diagram as a guide,
inspect wiring and connectors. Repair wiring harness as necessary. If
wiring and connectors are okay, go to next step.
19) Using scan tool, clear DTCs. Start engine and check for
DTCs. Wiggle wiring harness between TCC solenoid and PCM. If DTC P0743
resets, repair wiring harness as necessary. If DTC P0743 does not
reset, see INACTIVE DTC CONDITION under SELF-DIAGNOSTIC SYSTEM.
Testing is complete.
DTC P0748: GOVERNOR PRESSURE SOL CONTROL/TRANS RELAY CIRCUITS
Circuit Description
Circuit is monitored continuously while key is on. Code sets
if voltage detected on governor pressure solenoid control circuit at
the Powertrain Control Module (PCM) does not match desired voltage for\
4.8 seconds.
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 (AN & DN Bodies)
1) Using scan tool, read DTCs. If DTC P1765 is set, go to DTC
DTC P1765: TRANS 12-VOLT SUPPLY RELAY CNTRL CIRCUIT. If DTC P1765 is
not set, go to next step.
2) 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 5). If voltage is less than one
volt, go to next step.
3) Using scan tool, erase DTCs. Start engine. Using scan
tool, read DTCs while wiggling wiring harness between governor
pressure solenoid and PCM. If DTC P0748 resets, repair wiring harness
as necessary. If DTC P0748 does not reset, go to next step.
4) Inspect all related wiring and connectors. Repair as
necessary. If wiring and connectors are okay, see INACTIVE DTC
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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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replace PCM and see INACTIVE DTC CONDITION under SELF-DIAGNOSTIC
SYSTEM. Testing is complete.
DTC P0783: 3-4 SHIFT SOL, NO RPM DROP @ 3-4 SHIFT
Circuit Description
Circuit is monitored continuously while key is on and engine
running. Code sets if expected RPM drop does not occur within 4
seconds of requested gear change by PCM. Test must fail 3 times to set
code.
Possible Causes
* Transmission mechanically defective.
* TPS codes set.
* Transmission 3-4 solenoid wiring harness defective.
* Transmission fluid burnt or oil pan has excessive debris.
Diagnostic Procedures
1) Using scan tool, read DTCs. On all bodies except AB and WJ
bodies, go to next step. On AB and WJ bodies, if DTC SPECIFIC GOOD
TRIPS counter is not displayed or displayed count is not "0", go to
step 6). If DTC SPECIFIC GOOD TRIPS counter is displayed and displayed
count is "0", indicating DTC still exists, go to next step.
2) If any DTCs listed are present, perform appropriate
test(s). See 3-4 SHIFT SOLENOID TESTS table. If no DTCs are present,
go to next step.
3-4 SHIFT SOLENOID TESTS
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DTC Message Test
NO CAM SIGNAL AT PCM ..................................... ( 1) P0340
P/N SWITCH STUCK IN PARK OR IN GEAR .......................... P1899
Any Throttle Position Sensor (TPS) DTC ......................... ( 1)
TORQUE CONVERTOR CLUTCH SOLENOID/TRANS RELAY CIRCUITS ........ P0743
TRANS 12-VOLT SUPPLY RELAY CNTRL CIRCUIT ..................... P1765
TRANS 3-4 SHIFT SOLENOID/TRANS RELAY CIRCUITS ................ P0753
( 1) - See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
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3) 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.
4) 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 8).
5) 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.
6) Using scan tool, erase DTCs. Start engine. Road test
vehicle at 0-55 MPH with a constant 20 percent throttle. Repeat road
test 4 times. Note if DTC P0783 resets. If DTC P0783 resets, repair
wiring harness as necessary. If DTC P0783 does not reset, go to next
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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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necessary. See appropriate AUTOMATIC TRANSMISSION OVERHAUL article. If
transmission is okay, go to next step.
6) Replace governor pressure solenoid. Replace transmission
oil pan and refill fluid. Start engine. Read gauge pressure. If
pressure is less than 3 psi (.2 kg/cm
), testing is complete. If
pressure is 3 psi (.2 kg/cm) or greater, replace valve body.
7) 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 volts or
less, repair open 5-volt supply circuit. If voltage is greater than 4.
5 volts, replace governor pressure sensor.
8) Using scan tool, read and record FREEZE FRAME data. Ensure
CAUSED BY DTC hex code matches DTC message on screen. 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.
9) Using scan tool, clear DTCs. Drive vehicle at 0-20 MPH and
come to complete for 20 seconds. Repeat road test 5 times. Using scan
tool, monitor governor actual pressure and target pressure. If
pressures greater than 3 psi (.2 kg/cm
) at zero MPH appears, repair
wiring harness as necessary. If pressures greater than 3 psi (.2
kg/cm
) at zero MPH do not appear, testing is complete.
DTC P1762: GOV PRESS SEN OFFSET VOLTS TOO LOW OR HIGH
Circuit Description
Circuit is monitored continuously while key is on and engine
running. Code sets if governor pressure is out of range for 1.3
seconds. Test must fail 3 times to set code.
Possible Causes
* Solenoid pack connector 5 volt supply circuit open.
* Governor pressure sensor ground circuit open.
* Governor pressure sensor wiring harness and/or connectors
defective.
* Transmission fluid burnt or oil pan has excessive debris.
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 9).
If DTC SPECIFIC GOOD TRIPS counter is displayed and displayed count is
"0", go to next step.
2) Start engine and allow it to reach normal temperature.
Check transmission fluid level and condition. Correct transmission
fluid level or condition as necessary. If transmission fluid level and
condition are okay, go to next step.
3) Turn ignition off and back on. Do not start. Using scan
tool, check Park/Neutral Position (PNP) switch operation. Repair PNP
switch as necessary. If PNP switch operation is okay, go to next step.
4) Start engine. Place gear selector in Neutral. Using scan
tool, read GOV PRESSURE voltage. If voltage is not .30-.76 volt, go to
step 6). If voltage is as specified, go to next step.
5) While monitoring GOV PRESSURE sensor voltage, wiggle
connectors and wiring harness between governor pressure sensor and
PCM. If voltage changes while wiggling connectors and harness, repair
connector or harness as necessary. If voltage does not change,
conditions required to set DTC P1762 are not present at this time. DTC
P1762 sets if governor pressure sensor input is less than or greater
than a predetermined PNP switch calibration for 1.3 seconds under
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predetermined conditions. Possible causes are: faulty governor
pressure sensor, shorted or open 5-volt supply circuit or faulty PCM.
Testing is complete.
6) While monitoring GOV PRESSURE sensor voltage, wiggle
connectors and wiring harness between governor pressure sensor and
PCM. If voltage changes while wiggling connectors and harness, repair
connector or harness as necessary. If voltage does not change, go to
next step.
7) Read and record FREEZE FRAME data. 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 less than 4.5 volts, repair open 5-volt supply circuit.
If voltage is 4.5 volts or greater, go to next step.
8) Turn ignition off. Disconnect PCM harness connectors.
Inspect connectors and terminals for damage. Repair as necessary. If
connectors and terminals are okay, measure resistance of ground
circuit between transmission solenoid harness connector and Black PCM
harness connector C1. If resistance is 5 ohms or greater, repair open
ground circuit. If resistance is less than 5 ohms, go to next step.
9) Reconnect all harness connectors. Start engine. Use scan
tool to read and record FREEZE FRAME data. Erase DTCs. Start engine
and allow it to idle in Neutral or Park for 3 minutes. Read DTCs. If
DTC P1762 does not reset test is complete. If DTC P1762 resets, go to
next step.
10) Drain transmission fluid and remove oil pan. Replace
governor pressure sensor. Inspect oil pan for burnt oil and debris.
Repair transmission as necessary. See appropriate AUTOMATIC
TRANSMISSION OVERHAUL article. If transmission is okay, no problem is
found at this time. Testing is complete.
DTC P1763: GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH
Circuit Description
Circuit is monitored continuously while key is on and engine
running. Code sets if governor pressure signal voltage is greater than
4.89 volts for 8.5 seconds.
Possible Causes
* Solenoid pack connector 5 volt supply circuit open.
* Governor pressure sensor ground circuit open.
* Governor pressure sensor wiring harness and/or connectors
defective.
* Governor pressure/temperature sensor defective.
* Governor pressure sensor signal circuit short to voltage.
* Governor pressure sensor signal circuit open.
* PCM defective.
Diagnostic Procedures
1) Using scan tool read DTCs. If DTC SPECIFIC GOOD TRIPS
counter is not displayed or displayed count is not "0", go to step
22). If DTC SPECIFIC GOOD TRIPS counter is displayed and displayed
count is "0", indicating DTC still exists, 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
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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.