1999 DODGE RAM oil pressure

* 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

* Governor pressure sensor harness defective.
* Governor pressure/temperature sensor defective.
* Governor pressure sensor signal short to sensor ground
circuit.
* Governor pressure sensor signal circuit short to ground.
* Transmission harness/solenoid assembly defective.
* PCM defective.
* Solenoid pack connector 5-volt supply circuit open.
* Governor pressure sensor ground circuit open.
* Governor pressure sensor signal circuit short to voltage.
* Governor pressure sensor signal circuit open.
Diagnostic Procedures (AB, AN, DN & WJ Bodies)
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
11). If DTC SPECIFIC GOOD TRIPS counter is displayed and displayed
count is "0", go to next step.
2) Turn ignition off. Disconnect transmission solenoid
harness connector. 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 test DTC P1763: GOVERNOR PRESSURE
SENSOR VOLTS TOO HIGH. If voltage is 4.65 volts or less, go to next
step.
4) If voltage is less than .12 volt, go to next step. If
voltage is not .12-.80 volt, go to next step. If voltage is not as
specified, go to step 10).
5) Turn ignition off. Disconnect PCM harness connectors.
Disconnect transmission solenoid harness connector. Inspect connectors
and terminals for damage. Repair as necessary. If connector and
terminals are okay, measure resistance between sensor ground circuit
at Black PCM harness connector C1 and governor pressure sensor signal
circuit at White PCM harness connector C2. If resistance is less than
5 ohms, repair governor pressure sensor signal circuit for short to
ground circuit. If resistance is 5 ohms or greater, go to next step.
6) Measure resistance between ground and governor pressure
sensor signal circuit at governor pressure sensor harness connector.
If resistance is less than 5 ohms, repair governor pressure sensor
signal circuit for short to ground. If resistance is 5 ohms or
greater, go to next step.
7) Reconnect transmission solenoid harness connector. Drain
transmission fluid and remove oil pan. Disconnect governor
pressure/temperature sensor harness connector. Inspect connector and
terminals for damage. Repair as necessary. If connector and terminals
are okay, measure resistance between sensor ground circuit at Black
PCM harness connector C1 and governor pressure sensor signal circuit
at White PCM harness connector C2. If resistance is less than 5 ohms,
repair or replace transmission solenoid and harness assembly. If
resistance is 5 ohms or greater, go to next step.
8) Measure resistance between ground and governor pressure
sensor signal circuit at governor pressure sensor harness connector.
If resistance is less than 5 ohms, repair or replace transmission
solenoid and harness assembly. If resistance is 5 ohms or greater, go
to next step.
9) Reconnect all harness connectors except governor
pressure/temperature sensor harness connector. Turn ignition on. Using
scan tool, read governor pressure sensor voltage. If voltage is 4.8
volts or less, replace PCM. If voltage is greater than 4.8 volts,
replace governor pressure sensor.

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

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.

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

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)

NOTE: For additional information on fuel pressure and fuel pump
testing procedures, see appropriate NO TROUBLE CODE (NTC)
TEST and NO START (NS) TEST in SELF-DIAGNOSTICS - JEEP,
TRUCKS & RWD VANS article.
Vehicles With Fuel Rail Test Port
1) Disconnect negative battery cable. Release fuel pressure.
See FUEL PRESSURE RELEASE. Install fuel pressure gauge with hose on
fuel pressure test port.
2) Start engine and allow to idle. Fuel pressure should be
44-54 psi (3.1-3.8 kg/cm
). If no fuel pressure exists and engine will
not start, fuel pump relay and control circuit may be defective. See
FUEL PUMP RELAY.
3) If fuel pressure exceeds specification, fuel pump is okay,
but fuel pressure regulator is defective. Replace fuel pressure
regulator. Fuel pressure regulator is incorporated with the fuel
filter. Fuel filter/fuel pressure regulator is located on top of fuel
tank, in fuel pump module. See REMOVAL, OVERHAUL & INSTALLATION -
TRUCKS & RWD VANS - GASOLINE article.
Vehicles Without Fuel Rail Test Port
1) Disconnect negative battery cable. Release fuel pressure.
See FUEL PRESSURE RELEASE. Fuel pressure gauge is installed between
fuel supply line and fuel line fitting on fuel rail.
2) To disconnect fuel supply line from fuel rail, ensure area
around fuel supply line and fuel rail are clean. Note direction of
latch clip installation. Latch clip is located on top of fuel supply
line at fuel rail. See Fig. 1. Using 2 screwdrivers, pry latch clip
upward, and remove from fuel rail.
3) Pull fuel supply line from fuel rail. Install Adapter
(6923) into fuel rail. Ensure adapter is fully seated in fuel rail.
Install latch clip into fuel rail, with latch clip fingers pointing
downward. If latch clip will not fully seat so latch clip fingers
extend downward below fitting on fuel rail, adapter may not be fully
seated in fuel rail.
4) Connect fuel supply line to adapter. Ensure fuel supply
line fully seats in adapter. Remove protective cap from test port, and
install Fuel Pressure Gauge/Hose (5069) at test port.
5) Start engine and allow to idle. Fuel pressure should be
44-54 psi (3.1-3.8 kg/cm
). If no fuel pressure exists and engine will
not start, fuel pump relay and control circuit may be defective. See
FUEL PUMP RELAY.
6) If fuel pressure exceeds specification, fuel pump is okay,
but fuel pressure regulator is defective. Replace fuel pressure
regulator. Fuel pressure regulator is incorporated with the fuel
filter. Fuel filter/fuel pressure regulator is located on top of fuel
tank, in fuel pump module. See REMOVAL, OVERHAUL & INSTALLATION -
TRUCKS & RWD VANS - GASOLINE article.
7) On all models, release fuel pressure. See FUEL PRESSURE
RELEASE. Remove latch clip. Remove test equipment. Before reinstalling
fuel supply line, ensure fuel supply line fitting and fitting on fuel
rail are clean.
8) Lubricate fuel supply line fitting and fitting on fuel
rail with engine oil. Install fuel supply line on fuel rail.
9) Install latch clip into fuel rail, with latch clip fingers
pointing downward. Ensure latch clip is fully seated. Latch clip
fingers should extend downward below fitting on fuel rail when fully
seated.
10) Pull on fuel supply line to ensure fuel supply line is
fully locked on fuel rail. Reinstall negative battery cable. Start
engine and check for fuel leaks.