automatic transmission fluid DODGE RAM 1999 Service Repair Manual
[x] Cancel search | Manufacturer: DODGE, Model Year: 1999, Model line: RAM, Model: DODGE RAM 1999Pages: 1691, PDF Size: 40.34 MB
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ABBREVIATIONS
1999 Dodge Pickup R1500
GENERAL INFORMATION
COMMONLY USED ABBREVIATION
"A" ABBREVIATION TABLE
"A" ABBREVIATION TABLE
ABBREVIATION DEFINITION A Amperes A/C Air Conditioning A/T Automatic Transmission/Transaxle AAP Auxiliary Accelerator Pump AB Air Bleed ABCV Air Bleed Control Valve ABDC After Bottom Dead Center ABRS Air Bag Restraint System ABS Anti-Lock Brake System AC Alternating Current ACC A/C Clutch Compressor ACCS A/C Cycling Switch ACCUM Accumulator ACCY Accessory ACT Air Charge Temperature Sensor ACV Thermactor Air Control Valve ADJ Adjust or Adjustable ADV Advance AFS Airflow Sensor AI Air Injection AIR or A.I.R. Air Injection Reactor AIS Air Injection System ALCL Assembly Line Communications Link ALDL Assembly Line Diagnostic Link ARC Automatic ASCD Automatic ASCS Air Suction Control Solenoid ASD Auto Shutdown ASDM Air Bag System Diagnostic Module ASV Air Suction Valve ATC Automatic Temperature Control ATDC After Top Dead Center ATF Automatic Transmission Fluid ATS Air Temperature Sensor AXOD Automatic Transaxle Overdrive Abs. Absolute Accy. Accessory Alt. Alternator or Altitude Amp. Ampere Assy. Assembly Auto. Automatic Aux. Auxiliary Avg. Average
3
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![DODGE RAM 1999 Service Repair Manual The OD (Overdrive) OFF switch is located on instrument panel,\
to the right of steering column. The OD OFF switch controls overdrive
operation by delivering an input signal to PCM. The PCM u](/img/12/56915/w960_56915-220.png "DODGE RAM 1999 Service Repair Manual The OD (Overdrive) OFF switch is located on instrument panel,\
to the right of steering column. The OD OFF switch controls overdrive
operation by delivering an input signal to PCM. The PCM u")
The OD (Overdrive) OFF switch is located on instrument panel,\
to the right of steering column. The OD OFF switch controls overdrive
operation by delivering an input signal to PCM. The PCM uses this
signal for controlling operation of overdrive solenoid on the valve
body.
When overdrive switch is in the OFF position, OD light on
instrument panel will be illuminated and transmission will not upshift
into 4th gear for overdrive operation. When OD switch is in the ON
position, OD light on instrument panel will not be illuminated and
transmission will upshift into 4th gear for overdrive operation.
If OD switch is in the ON position, the TCC will lock-up when
transmission is in 4th gear with vehicle speed greater than 45 MPH. If
overdrive switch is in the OFF position, the TCC will lock-up when
transmission is in 3rd gear with vehicle speed greater than 35 MPH at
light throttle application.
THROTTLE POSITION (TP) SENSOR
The TP sensor delivers an input signal to the PCM to indicate
throttle position. The PCM uses this input signal for controlling TCC
operation, governor pressure and upshift into 4th gear for overdrive
operation.
TRANSMISSION FLUID TEMPERATURE SENSOR
NOTE: Transmission fluid temperature sensor may also be referred to
as transmission fluid temperature thermistor or transmission
fluid temperature sender.
Transmission fluid temperature sensor delivers an input
signal to the PCM to indicate transmission fluid temperature. The PCM
uses this input signal for controlling the TCC, overdrive operation
and governor pressure. Transmission fluid temperature sensor is
located on the valve body and is integral with governor pressure
sensor. See Fig. 1.
OUTPUT SHAFT SPEED SENSOR
NOTE: Output shaft speed sensor may also be referred to as
transmission shaft speed sensor or shaft speed sensor.
Output shaft speed sensor is located on overdrive unit
attached to rear of transmission. Output shaft speed sensor is mounted
above the lugs on park gear in the overdrive unit. Speed sensor input
signals are generated when lugs on park gear rotate past face of
sensor. Input signals are delivered to PCM. The PCM uses this input
signal for controlling transmission operation. The Vehicle Speed
Sensor (VSS) also serves as a back-up to the output shaft speed
sensor. The VSS signal is also an input to the PCM.
TROUBLE SHOOTING
* PLEASE READ THIS FIRST *
NOTE: For symptom trouble shooting, see appropriate AUTOMATIC
TRANSMISSION OVERHAUL article.
PRELIMINARY INSPECTION
Visually inspect all electrical wiring, looking for chafed,
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stretched, cut or pinched wiring. Ensure electrical connectors fit
tightly and are not corroded. Check PCM, sensors and switches for
physical damage. Check engine coolant level. Check transmission fluid
level and condition.
SELF-DIAGNOSTIC SYSTEM
* PLEASE READ THIS FIRST *
NOTE: Only transaxle-related trouble codes are listed. For engine-
related DTC definitions, see TROUBLE CODE DEFINITIONS article
in APPLICATIONS & IDENTIFICATION. For engine-related DTC
diagnosis, see appropriate SELF-DIAGNOSTICS article in ENGINE
PERFORMANCE. Engine performance DTCs must be repaired first,
as engine performance and related component signals will
affect transaxle operation and diagnosis.
DIAGNOSTIC PROCEDURE
When performing vehicle diagnosis:
* Ensure transmission fluid level is correct and fluid is
neither contaminated or aerated.
* Ensure shift cable is properly adjusted. See appropriate
AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION
SERVICING.
* Ensure battery is fully charged.
* Perform visual inspection, ensuring all electrical
connections at transmission, PCM, TP sensor and output shaft
speed sensor are clean and properly installed.
* Retrieve DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES.
* Repair DTCs in order displayed.
* Always perform test verification test after any repair
procedure is completed unless specified otherwise. See
appropriate verification test under DIAGNOSTIC TESTS.
NOTE: Self-diagnostic tests are written specifically for Chrysler's
Diagnostic Readout Box (DRB) scan tool. A generic scan tool
may be used, but may not be capable of performing all
necessary test functions.
TEST EQUIPMENT HOOK-UP
Generic Scan Tool & DVOM
Self-diagnostic tests are written specifically for Chrysler's
Diagnostic Readout Box (DRB) scan tool. The DRB has a built-in DVOM
function. A generic scan tool may be used, but may not be capable of
performing all necessary test functions. If DRB test procedures
require resistance or voltage to be measured using scan tool in
ohmmeter or voltmeter mode, connect DVOM ground lead to DLC connector
terminal No. 4 and positive lead to terminal specified in test
procedure.
DRB Scan Tool
Refer to DRB scan tool instructions to read and clear DTCs,
and when performing other scan tool functions. DRB scan tool is
grounded through DLC connector terminal No. 4. Only one volt/ohmmeter
test lead is required to measure voltage or resistance. See Fig. 2.
RETRIEVING DIAGNOSTIC TROUBLE CODES
NOTE: Manufacturer recommends using Chrysler's Diagnostic Readout
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![DODGE RAM 1999 Service Repair 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 Repair 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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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
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![DODGE RAM 1999 Service Repair Manual (1) - See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. \
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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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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