relay DODGE RAM 1999 Service Owner's Guide
[x] Cancel search | Manufacturer: DODGE, Model Year: 1999, Model line: RAM, Model: DODGE RAM 1999Pages: 1691, PDF Size: 40.34 MB
Page 248 of 1691
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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connectors and terminals are okay, measure resistance between ground
and 3-4 shift solenoid control circuit at PCM harness connector. If
resistance is 5 ohms or greater, go to next step. If resistance is
less than 5 ohms, repair short to ground in 3-4 shift solenoid
circuit.
6) Measure resistance of 3-4 shift solenoid circuit between
White PCM harness connector C2 and transmission solenoid harness
connector. If resistance is 5 ohms or greater, repair open 3-4 shift
solenoid circuit. If resistance is less than 5 ohms, go to next step.
7) Turn ignition on. Measure voltage between ground and 3-4
shift solenoid control circuit at PCM harness connector. If voltage is
greater than one volt, repair 3-4 shift solenoid control circuit for
short to voltage. If voltage is one volt or less, go to next step.
8) Turn ignition off. 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 3-4 shift solenoid control
circuit at White PCM harness connector C2. If resistance is 26-40
ohms, go to next step. If resistance is not 26-40 ohms or less,
replace 3-4 shift solenoid.
9) Measure resistance between ground and transmission control
relay output circuit at transmission control relay 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.
10) Measure resistance between transmission control relay
output circuit between transmission control relay connector and
transmission solenoid harness connector. If resistance is 5 ohms or
greater, repair open transmission control relay output circuit. If
resistance is less than 5 ohms, go to next step.
11) 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, replace PCM.
12) Disconnect transmission control relay. Inspect connector
and terminals for damage. Repair as necessary. If connector and
terminals are okay, turn ignition on. Replace transmission control
relay. Using scan tool, actuate transmission control relay. Measure
voltage between ground and transmission relay output circuit at
transmission solenoid harness connector. If voltage is greater than 10
volts, replace transmission control relay. If voltage is 10 volts or
less, go to next step.
13) Measure resistance of transmission control relay output
circuit between transmission control relay connector solenoid harness
connector. If resistance is 5 ohms or greater, repair open in
transmission control relay output circuit. If resistance is less than
5 ohms, go to next step.
14) Measure resistance of transmission control relay output
circuit between ground and transmission control relay connector. If
resistance is 5 ohms or greater, go to next step. If resistance is
less than 5 ohms, repair short to ground in transmission control relay
output circuit.
15) 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, test is complete.
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, 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,
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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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step.
7) Turn engine off. Drain transmission fluid and remove oil
pan. 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, see INACTIVE
DTC CONDITION under SELF-DIAGNOSTIC SYSTEM. Testing is complete.
8) Leave gauges connected. Replace 3-4 shift solenoid.
Replace transmission pan and fill with fluid. 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, no
problem is found at this time. 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.
DTC P1740: TCC OR O/D SOLENOID PERFORMANCE (BR BODY - DIESEL)
Circuit Description
Torque Converter Clutch (TCC) and overdrive clutch are tested\
when Powertrain Control Module (PCM) requests TCC engagement in 3rd
gear and overdrive. Code will set if expected RPM drop is not achieved
while attempting to engage TCC and/or overdrive. Code indicates
malfunctioning torque converter or overdrive clutch.
Possible Causes
* Fluid level or quality problem.
* Transmission wiring and connector defective.
* Transmission mechanically defective.
* Low fuel level.
* Trans temperature below 32
.
* Transfer case is in low range.
* Engine RPM trouble codes set.
* Misfire trouble code set (DTCs P0300-P0306).
* Output shaft speed trouble code set.
* PTO is engaged.
* TPS codes set (DTCs P0121-P0123).
* Torque converter 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
16). If DTC SPECIFIC GOOD TRIPS counter is displayed and displayed
count is "0", go to next step.
2) If any DTCs listed are present, perform appropriate
test(s). See TCC OR O/D SOLENOID TESTS table. If no DTCs are present,
go to next step.
TCC OR O/D SOLENOID TESTS
\
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\
DTC Message Test
CAMSHAFT POSITION SENSOR SIGNAL .......................... ( 1) P0341
P/N SWITCH STUCK IN PARK OR IN GEAR .......................... P1899
Any Throttle Position Sensor (TPS) DTC ......................... ( 1)
Any Misfire DTC ................................................ ( 1)
Any Engine RPM DTC ............................................. ( 1)
Any Output Shaft Speed Sensor DTC .............................. ( 1)
TRANS 12-VOLT SUPPLY RELAY CNTRL CIRCUIT ..................... P1765
TORQUE CONVERTOR CLUTCH SOLENOID/TRANS RELAY CIRCUITS ........ P0743
TRANS 3-4 SHIFT SOLENOID/TRANS RELAY CIRCUITS ................ P0753
Page 254 of 1691
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
15). 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. See DIAGNOSTIC TROUBLE CODES (DTC) & DRB MESSAGES table.
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 7).
4) Turn ignition off. Install a pressure gauge at
transmission 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 5 psi (.3 kg/cm
), go to step 12). If pressure is 5 psi (.3
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
necessary. See appropriate AUTOMATIC TRANSMISSION OVERHAUL article. If
transmission is okay, go to next step.
6) Replace governor pressure solenoid. Start engine. Read
gauge pressure. If pressure is less than 5 psi (.3 kg/cm
), testing is
complete. If pressure is 5 psi (.3 kg/cm) or greater, replace valve
body.
NOTE: Removing transmission control relay in the following step may
set other DTCs. Disregard these DTCs.
7) Place gear selector in Park. With engine still running,
remove transmission control relay. Depress brake pedal and place gear
selector in "D" position. Read governor pressure sensor value. If
value is 40-55 psi (2.8-3.9 kg/cm
), go to next step. If value is not
as specified, go to step 10).
8) Turn engine off. Install transmission control relay. Drive
vehicle at 25-30 MPH. Using scan tool, monitor governor actual
pressure and target pressure. If pressures do not stay consistently
within 5 psi (.3 kg/cm
) of each other within 3 seconds, go to next
step. If pressures stay consistently within 5 psi (.3 kg/cm) of each
other, test is complete.
9) Replace governor pressure solenoid. Drive vehicle at 25-30
MPH. Using scan tool, monitor governor actual pressure and target
pressure. If pressures do not stay consistently within 5 psi (.3
kg/cm
) of each other, repair internal transmission leakage problem.
If pressures stay consistently within 5 psi (.3 kg/cm) of each other,
testing is complete.
10) On all bodies except WJ body, go to next step. On WJ
body, turn ignition on, engine off. Measure voltage (backprobe)
between ground and 5-volt supply circuit at transmission solenoid
harness connector. If voltage is 4.5 volts or less, repair 5-volt
supply circuit for low voltage. If voltage is greater than 4.5 volts,
go to next step.
11) Turn ignition off. Install transmission control relay.
Install a pressure gauge at governor pressure test port. See TESTING
in appropriate AUTOMATIC TRANSMISSION OVERHAUL article. 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
), go to next step. If pressure is not as
specified, go to step 13).
12) Turn ignition off. Disconnect transmission solenoid
harness connector. Inspect connector and terminals for damage. Repair
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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
Page 258 of 1691
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, go to step 11).
4) 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
signal circuit between transmission solenoid harness connector and
White PCM harness connector C2. If resistance is greater than 5 ohms,
repair open governor pressure sensor signal circuit. If resistance is
5 ohms or less, go to next step.
5) Measure resistance of sensor ground circuit between Black
PCM harness connector C1 and transmission solenoid harness connector.
If resistance is greater than 5 ohms, repair open ground circuit. If
resistance is 5 ohms or less, go to next step.
6) Connect a fused jumper wire between fused B+ circuit and
transmission control relay output circuit at transmission relay
connector. Turn ignition on. Measure voltage between ground and
governor pressure signal circuit at White PCM harness connector C2. If
voltage is greater than 10 volts, repair governor pressure signal
circuit for short to voltage. If voltage is 10 volts or less, go to
next step.
7) Turn ignition off. Drain transmission fluid and remove oil
pan. Reconnect transmission solenoid harness connector. Disconnect
governor pressure sensor harness connector. Inspect connector and
terminals for damage. Repair as necessary. If connector and terminals
are okay, 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.
8) Reconnect all harness connectors except governor pressure
sensor harness connector. Carefully connect a fused jumper wire
between ground circuit and governor pressure signal circuit at
governor pressure sensor harness connector. Turn ignition on. Using
scan tool, read governor pressure sensor voltage. If voltage is .1
volt or less, replace governor pressure sensor. If resistance is
greater than .1 volt, go to next step.
9) 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
or replace transmission solenoid and harness assembly. If resistance
is 5 ohms or less, go to next step.
10) Turn ignition on. Measure voltage between ground and
governor pressure signal circuit at governor pressure sensor harness
connector. If voltage is greater than one volt, repair or replace
transmission solenoid and harness assembly. If voltage is one volt or
less, replace PCM.
11) If governor pressure voltage is less than .12 volt, go to
DTC P1764: GOVERNOR PRESSURE SENSOR VOLTS TOO LOW. If governor
pressure voltage is .12 volt or greater, go to next step.
12) If governor pressure voltage is .12-.80 volt, go to next
step. If governor pressure voltage is .80 volt or greater, go to step
15).
13) 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, go next step.
14) 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 8.36 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-
Page 263 of 1691
9) Check and record freeze frame data to determine conditions
which set code. 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.
10) 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 governor pressure sensor signal circuit. If resistance is 5 ohms
or less, go to next step.
11) Connect a fused jumper wire between fused B+ circuit and
transmission control relay output circuit at transmission relay
connector. 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.
12) 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. Carefully
connect a fused jumper wire between ground circuit and governor
pressure signal circuit at governor pressure sensor harness connector.
Turn ignition on. Using scan tool, read governor pressure sensor
voltage. If voltage is .1 volt or less, replace pressure/temperature
sensor. If voltage is greater than .1 volt, go to next step.
13) 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
or replace transmission solenoid and harness assembly. If resistance
is 5 ohms or less, go to next step.
14) 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.
15) Turn ignition on. Measure voltage between ground and
governor pressure signal circuit at governor pressure sensor harness
connector. If voltage is greater than one volt, repair or replace
transmission solenoid and harness assembly. If voltage is one volt or
less, replace PCM.
16) 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 of sensor ground circuit
between Black PCM harness connector C1 and solenoid harness connector.
If resistance is less than 5 ohms, go to next step. If resistance is 5
ohms or greater, repair open in governor pressure sensor ground
circuit.
17) Turn ignition on. Measure voltage between ground and
governor pressure signal circuit at governor pressure sensor harness
connector. 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.
18) Turn ignition off. Measure resistance of governor
pressure sensor signal circuit between White PCM harness connector C2
and solenoid harness connector. If resistance is greater than 5 ohms,
repair open governor pressure sensor signal circuit. If resistance is
5 ohms or less, go to next step.
Page 264 of 1691
19) Turn ignition on. Using scan tool, read governor pressure
sensor voltage. If voltage is 4.65 volts or less, replace PCM. If
resistance is greater than 4.65 volts, go to next step.
20) Turn ignition off. 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 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 or replace transmission solenoid and harness assembly. If
resistance is 5 ohms or less, go to next step.
21) 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.
22) Turn ignition on. Measure voltage between ground and
governor pressure signal circuit at governor pressure sensor harness
connector. 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.
23) Check and record freeze frame data to determine
conditions which set code. Conditions required to set DTC P1764 are
not present at this time. 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.
24) Using scan tool, clear DTCs. While reading DTCs, wiggle
wiring harness between PCM and governor pressure sensor. If DTC P1764
resets while wiggling wiring harness, repair wiring harness as
necessary. If DTC P1764 does not reset, go next step.
25) DTC P1764 sets if governor pressure sensor input is less
than .1 volt for 8.36 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.
DTC P1765: TRANS 12-VOLT SUPPLY RELAY CNTRL CIRCUIT
Circuit Description
Circuit is monitored continuously while key is on. Code sets
if voltage on transmission control relay circuit at PCM is different
than expected voltage for 3 seconds.
Possible Causes
* Generator source circuit open.
* Transmission relay control circuit open.
* Transmission relay control circuit short to ground.
* Transmission control relay wiring harness defective.
* PCM defective.
* Transmission control relay 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 9).
If DTC SPECIFIC GOOD TRIPS counter is displayed and displayed count is
"0", go to next step.
2) Using scan tool, actuate transmission control relay. If
transmission control relay does not click, go to step 5). If
transmission control relay clicks, go to next step.
3) Wiggle wiring harness between transmission control relay
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and PCM. Ensure scan tool is still actuating transmission control
relay. If transmission control relay stops clicking, repair wiring
harness as necessary. If transmission control relay continues
clicking, 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) Remove transmission control relay. Inspect connector and
terminals for damage. Repair as necessary. If connector and terminals
are okay, turn ignition on. Using scan tool, actuate generator field.
Measure voltage between ground and generator source circuit at
transmission control relay harness connector. If voltage is 10 volts
or less, repair open generator source circuit. If voltage is greater
than 10 volts, go to next step.
6) Turn ignition off. Measure resistance between transmission
control relay terminals No. 85 and 86. If resistance is 100 ohms or
greater, replace transmission control relay. If resistance is less
than 100 ohms, go to next step.
7) Disconnect White PCM harness connector C2. Inspect
connector and terminals for damage. Repair as necessary. If connector
and terminals are okay, measure resistance between ground and
transmission relay control circuit at White PCM harness connector C2.
If resistance is less than 5 ohms, repair short to ground in
transmission relay control circuit. If resistance is 5 ohms or
greater, go to next step.
8) Measure resistance of transmission relay control circuit
between transmission control relay connector and White PCM harness
connector C2. If resistance is 5 ohms or greater, repair open
transmission relay control circuit. If resistance is less than 5 ohms,
replace PCM.
9) Conditions required to set DTC P1765 are not present at
this time. DTC P1765 sets if transmission control relay is not in a
state requested by PCM for greater than 3 seconds. Possible causes
are: faulty relay, open or shorted control circuit, faulty PCM or
faulty connector terminals. Inspect all related wiring and connectors.
Repair as necessary. If wiring and connectors are okay, erase DTCs.
Using scan tool, read DTCs while wiggling wiring harness between
governor pressure sensor and PCM. If DTC P1765 resets, repair wiring
harness as necessary. If DTC P1765 does not reset, see INACTIVE DTC
CONDITION under SELF-DIAGNOSTIC SYSTEM. Testing is complete.
DTC P1899: P/N SWITCH STUCK IN PARK OR IN GEAR
Circuit Description
Circuit is monitored with transmission in "D", "N" or "P"
position. Code sets if PCM detects an incorrect park/neutral switch
state for any given mode of vehicle operation.
Possible Causes
* Park Neutral Position (PNP) switch wiring harness
defective.
* PNP switch sense circuit open.
* PNP switch defective.
* PNP switch sense circuit short to ground.
* PNP switch stuck.
Diagnostic Procedures (AN, DN & WJ Bodies)
1) Using scan tool, read DTCs. On AN and DN bodies, go to
next step. On WJ body, 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",