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
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
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
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
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-
* PCM defective.
* Governor pressure sensor signal circuit short to voltage.
* Governor pressure sensor ground circuit open.
* Governor pressure sensor signal circuit open.
* Governor pressure/temperature sensor defective.
Diagnostic Procedures
1) Disconnect White PCM harness connector C2. Inspect
connectors and terminals for damage. Repair as necessary. If connector
and terminals are okay, 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.
2) Turn ignition off. Disconnect all PCM harness connectors.
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, 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.
3) 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 governor pressure sensor signal circuit at
transmission solenoid harness connector. If voltage is greater than
one volt, repair governor pressure signal circuit for short to
voltage. If voltage is not as specified, go to next step.
4) Reconnect transmission solenoid harness connector. 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 or replace transmission
solenoid and harness assembly. If resistance is 5 ohms or less, go to
next step.
5) Turn ignition off. Disconnect transmission solenoid
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 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.
6) 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.
7) Reconnect transmission solenoid harness connector. 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.
DTC P1764: GOVERNOR PRESSURE SENSOR VOLTS TOO LOW
Circuit Description
Circuit is monitored continuously while key is on and engine
running. Code sets if governor pressure is less than .1 volt for 8.5
seconds.
Possible Causes
TRIP COUNTER displays "0", return to appropriate test(s). If DTC
SPECIFIC GOOD TRIP COUNTER displays one or more, repair is complete.
Go to step 9).
3) If coming to this test from a mis-fire DTC test, go step
7). If coming to this test from other than a mis-fire DTC test, use
scan tool to monitor pretest enabling conditions until all conditions
have been met. Once all enabling conditions are met, observe
appropriate monitor for DTC on scan tool and go to next step.
4) Using scan tool, monitor SIMILAR CONDITIONS to attempt to
duplicate conditions that vehicle was operating at when DTC was set.
If conditions can be duplicated, GOOD TRIP COUNTER will change to one
or more. Monitor operation may be observed on scan tool. All specified
enabling conditions for specified DTC must be met before PCM will
operate monitor. Go to next step.
5) Turn ignition off for 10 seconds. Start engine and allow
it to idle for 2 minutes while monitoring scan tool. If STARTS SINCE
SET and DTC SPECIFIC GOOD TRIP COUNTER change to one or more, repair
is complete. Go to step 9). If STARTS SINCE SET and DTC SPECIFIC GOOD
TRIP COUNTER do not change to one or more, go to next step.
6) Using scan tool, read DTCs. If any DTC exists, return to
appropriate test(s). If no other DTC exists, go to next step.
7) Using scan tool, monitor SIMILAR CONDITIONS to attempt to
duplicate conditions that vehicle was operating at when DTC was set.
If conditions can be duplicated, MISFIRE GOOD TRIP COUNTER will change
to one or more. If MISFIRE GOOD TRIP COUNTER changes to one or more,
test is complete. Go to step 9). If MISFIRE GOOD TRIP COUNTER does not
change to one or more, go to next step.
8) Using scan tool, read DTCs. If any DTC exists, return to
appropriate test(s). If no other DTC exists, go to next step.
9) Turn ignition on, with engine off. Using scan tool, erase
DTCs. Turn ignition off. Disconnect scan tool. Test is complete.
REMOVAL & INSTALLATION
GOVERNOR PRESSURE SENSOR, GOVERNOR PRESSURE SOLENOID &
TRANSMISSION FLUID TEMPERATURE SENSOR
NOTE: Transmission fluid temperature sensor is integral with
governor pressure sensor.
Removal
1) Raise and support vehicle. Drain transmission fluid.
Remove transmission oil pan and filter. Disconnect harness connectors
from governor pressure solenoid and sensor.
2) Remove pressure solenoid retainer-to-governor body screws.
Separate solenoid retainer from governor and pull solenoid from
governor body.
3) Remove governor body-to-valve body bolts. Separate
governor body from valve body. Remove governor body and gasket. Remove
retainer clip holding pressure sensor to governor body and remove
pressure sensor.
Installation
1) Clean all gasket surfaces. Lubricate NEW "O" ring with ATF
and install on pressure sensor. Push pressure sensor into governor
body and install retainer clip. Position governor body on valve body
with NEW gasket and install governor body-to-valve body bolts.
2) Lubricate NEW "O" ring with ATF and install on pressure
solenoid. Push solenoid into governor body. Install solenoid retainer.
Reconnect harness connectors to pressure solenoid and sensor. To
complete installation, reverse removal procedure.
F - B ASIC T E STIN G - R W D - G ASO LIN E
1999 D odge P ic ku p R 1500
1999 ENGINE PERFORMANCE
CHRY - Basic Diagnostic Procedures Trucks & RWD Vans
Dakota, Durango, Ram Pickup, Ram Van, Ram Wagon
CAUTION: When battery is disconnected, vehicle computer and memory
systems may lose memory data. Driveability problems may exist
until computer systems have completed a relearn cycle. See
COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION
before disconnecting battery.
INTRODUCTION
The following diagnostic steps will help prevent overlooking
a simple problem. This is also where to begin diagnosis for a no-start
condition.
The first step in diagnosing any driveability problem is
verifying the customer's complaint with a test drive under the
conditions the problem reportedly occurred.
Before entering self-diagnostics, perform a careful and
complete visual inspection. Most engine control problems result from
mechanical breakdowns, poor electrical connections or
damaged/misrouted vacuum hoses. Before condemning the computerized
system, perform each test listed in this article.
NOTE: Perform all voltage tests with a Digital Volt-Ohmmeter (DVOM)\
with a minimum 10-megohm input impedance, unless stated
otherwise in test procedure.
PRELIMINARY INSPECTION & ADJUSTMENTS
VISUAL INSPECTION
Visually inspect all electrical wiring, looking for chafed,
stretched, cut or pinched wiring. Ensure electrical connectors fit
tightly and are not corroded. Ensure vacuum hoses are properly routed
and are not pinched or cut. Inspect air induction system for possible
vacuum leaks.
MECHANICAL INSPECTION
Compression
Ensure battery is fully charged. Warm engine to normal
operating temperature. Disconnect wire at ignition coil to prevent
engine from starting. Check engine compression with all spark plugs
removed and throttle wide open.
Check engine mechanical condition with a compression gauge,
vacuum gauge, or an engine analyzer. See engine analyzer manual for
specific instructions.
COMPRESSION SPECIFICATIONS
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Application Specification
Compression Ratio
Ram Pickup (8.0L) .......................................... 8.4:1\
All Others ................................................. 9.1:1
Normal Compression Pressure .................................... ( 1)