Dodge Ram Truck 1500-2500-3500. Manual — part 1730

P0868-GOVERNOR PRESSURE SENSOR VOLTS TOO HI (DIESEL) (CONTINUED)

10.

ENGINE CONTROL MODULE

Turn the ignition off to the lock position.

Reconnect the ECM harness connector.

Reconnect the Transmission Solenoid Assembly harness connector.

Ignition on, engine not running.

With the scan tool, erase DTCs.

Connect a jumper wire between the (T38) Governor Pressure Sensor
Signal circuit and the (K900) Sensor Ground circuit in the Transmis-
sion Governor Pressure Sensor harness connector.

With the scan tool, read DTCs.

Did the DTC P0869 set?

Yes

>> Replace the Governor Pressure Sensor per the Service

Information. (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 48RE/GOVERNOR PRESSURE SENSOR -
REMOVAL)

Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCE-
DURE)

No

>> Using the schematics as a guide, check the Engine Control Module (ECM) pins, terminals, and connec-

tors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground cir-
cuits. If no problems are found, replace and program the ECM per the Service Information. (Refer to 8
- ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CONTROL MODULE - REMOVAL)

Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)

11.

INTERMITTENT WIRING AND CONNECTORS

The conditions necessary to set this DTC are not present at this time.

Use the Freeze Frame Data to help duplicate the conditions in which the DTC originally set. Pay particular attention
to the DTC set conditions, such as, VSS, MAP, ECT, and Load

Using the schematics as a guide, visually inspect the related wiring harness. Look for any chafed, pierced, pinched,
or partially broken wires.

Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.

Wiggle the wiring and connectors while checking for any possible open or shorted circuits.

Check for any Service Information Tune-ups or Technical Service Bulletins that may apply.

Were there any problems found?

Yes

>> Repair as necessary.

Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)

No

>> Test Complete.

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AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P0869-GOVERNOR PRESSURE SENSOR VOLTS TOO LOW (DIESEL)

DR/DH

AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P0869-GOVERNOR PRESSURE SENSOR VOLTS TOO LOW (DIESEL) (CONTINUED)

For the Transmission circuit diagram (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - SCHE-
MATICS AND DIAGRAMS)

For a complete wiring diagramRefer to Section 8W

Theory of Operation

The Governor Pressure Sensor is used by the ECM to adjust the Governor Pressure to a desired level for shifts in
first, second, and third gear. If the ECM detects the monitored sense voltage is greater than or less than a prede-
termined specification, the ECM will set the desired DTC.

•

When Monitored:
Continuously with the ignition on and the engine running.

•

Set Condition:
This DTC will set if the monitored voltage from the Governor Pressure Sensor drops below 0.12 volts for the
period of 8.5 seconds.

Possible Causes

PARK NEUTRAL DTC PRESENT OR OTHER TRANSMISSION DTC’S PRESENT

(T38) GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT SHORT TO GROUND

(T38) GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT SHORT TO OTHER CIRCUITS

TRANSMISSION SOLENOID ASSEMBLY

GOVERNOR PRESSURE SENSOR

ENGINE CONTROL MODULE

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)

Diagnostic Test

1.

CHECK IF THE DTC IS CURRENT

Ignition on, engine not running.

With the scan tool, read Engine DTCs.

Record the Freeze Frame data for the reported DTC.

With the scan tool, erase DTCs.

Turn the ignition off to the lock position.

Using the Freeze Frame data recorded earlier, try to duplicate the conditions in which the DTC originally set.

NOTE: It may be necessary to road test the vehicle to duplicate the original set conditions.
With the scan tool, read Engine DTCs.

Did the DTC reset?

Yes

>> Go To 2

No

>> Go To 7

2.

CHECK FOR OTHER TRANSMISSION DTC’S PRESENT

Are there any Park/Neutral or other Transmission DTCs present?

Yes

>> Refer to the Transmission category and perform the appropriate symptom(s). If a Park/Neutral DTC is

present, perform its respective test first. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC -
48RE - DIAGNOSIS AND TESTING)

No

>> Go To 3

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P0869-GOVERNOR PRESSURE SENSOR VOLTS TOO LOW (DIESEL) (CONTINUED)

3.

CHECK THE (T38) GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND

Turn the ignition off to the lock position.

Disconnect the Transmission Solenoid Assembly harness connector.

Disconnect the ECM C1 and C2 harness connectors.

NOTE: Check connectors - Clean/repair as necessary
Measure the resistance between Ground and the (T38) Governor
Pressure Sensor Signal circuit in the Transmission Solenoid Assembly
harness connector.

Is the resistance greater than 100k ohms?

Yes

>> Go To 4

No

>> Repair the (T38) Governor Pressure Sensor Signal circuit

for a short to ground.

Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCE-
DURE)

4.

CHECK THE (T38) GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO ANOTHER
CIRCUIT

Measure the resistance between the (T38) Governor Pressure Sensor
Signal circuit and all other circuits in the Transmission Solenoid
Assembly harness connector.

Is the resistance below 100k ohms between the (T38) Governor
Pressure Sensor Signal circuit and any other circuit(s) in the
Transmission Solenoid Assembly harness connector?

Yes

>> Repair the (T38) Governor Pressure Sensor Signal circuit

for a short to another circuit(s).

Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 48RE - STANDARD PROCEDURE)

No

>> Go To 5

DR/DH

AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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