Page 3761 of 5267

3.CHECKING FOR GOVERNOR PRESSURE ABOVE 6 PSI
Start the engine.
CAUTION: Apply the parking brake.
Warm the transmission to a normal operating temperature above 43° C (110° F).
CAUTION: Firmly apply the brakes.
With the engine RPM at idle, place the gear selector in Drive.
With the scan tool, read the governor pressure.
Is the governor pressure above 41.4 kPa (6 psi)?
Ye s>>
Go To 4
No>>
Go To 11
4.GOVERNOR PRESSURE MATCH GAUGE PRESSURE
Turn the ignition off to the lock position.
Install a 700 kPa (100 psi) pressure gauge to the Governor Pressure Test Port. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - DIAGNOSIS AND TESTING)
Start the engine.
Warm the transmission to a normal operating temperature above 43° C (110° F).
CAUTION: Firmly apply the brakes.
With the engine RPM at idle, place the gear selector in Drive.
With the scan tool, read the governor pressure and compare the scan tool reading to the pressure gauge reading.
Does the scan tool Governor Pressure reading match the pressure gauge reading within 6.9 kPa (1
psi)?
Ye s>>
Go To 5
No>>
Go To 8
5.CHECK FOR BURNT TRANSMISSION FLUID AND/OR EXCESSIVE DEBRIS IN THE TRANSMISSION OIL
PA N
Turn the ignition off to the lock position.
Remove the transmission oil pan per the Service Information and inspect for burnt transmission fluid and excessive
debris. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE/FLUID - STANDARD PROCEDURE)
Is the transmission fluid burnt or does the transmission oil pan contain excessive debris?
Ye s>>
Repair internal transmission as necessary. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC -
48RE - REMOVAL)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Go To 6
6.REPLACE THE GOVERNOR PRESSURE SOLENOID AND CHECK THE VALVE BODY
Replace the Governor Pressure Solenoid per with the Service Information.(Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 48RE/GOVERNOR PRESSURE SENSOR - REMOVAL)
Start the engine.
Warm the transmission to a normal operating temperature above 43° C (110° F).
CAUTION: Firmly apply the brakes.
With the engine RPM at idle, place the gear selector in Drive.
Read the governor pressure on the pressure gauge.
Is the governor pressure on the pressure gauge above 41.4 kPa (6 psi) with the engine RPM at idle and
Page 3762 of 5267

the gear selector in Drive?
Ye s>>
Replace the Valve Body per the Service Information. (Refer to 21 - TRANSMISSION/TRANSAXLE/AU-
TOMATIC - 48RE/VALVE BODY - REMOVAL)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Go To 7
7.ENGINE CONTROL MODULE
Turn the ignition off to the lock position.
Remove pressure gauge from transmission.
Install the Transmission Oil Pan and refill the transmission fluid per theservice information. (Refer to 21 - TRANS-
MISSION/TRANSAXLE/AUTOMATIC - 48RE/FLUID - STANDARD PROCEDURE)
With the scan tool, erase Engine DTCs.
Test drive the vehicle.
Be sure to stop the vehicle, with the vehicle in drive on six separate occurrences for at least 6 seconds each stop.
With the scan tool, read Engine DTCs.
Did the P1757 DTC reset?
Ye s>>
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 attentiontoallpowerandgroundcir-
cuits. If no problems are found, replace and program the ECM per the ServiceInformation. (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)
No>>
Go To 11
8.CHECK THE 5 VOLT SUPPLY CIRCUIT FOR AN OPEN
Turn the ignition off to the lock position.
Disconnect the ECM harness connectors.
Disconnect the Transmission Solenoid Assembly harness connector.
Measure the resistance of the 5- volt Supply circuit between the Trans-
mission Solenoid Assembly harness connector and the ECM harness
connector.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 9
No>>
Repair the 5-volt Supply circuit for an open.
Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 48RE - STANDARD PROCEDURE)
Page 3763 of 5267

9.CHECK THE 5 VOLT SUPPLY CIRCUIT FOR AN OPEN INSIDE THE TRANSMISSION
Reconnect the Transmission Solenoid Assembly harness connector.
Remove the transmission oil pan per the Service Information. (Refer to
21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE/FLUID -
STANDARD PROCEDURE)
Disconnect the Governor Pressure Sensor connector internal to the
transmission.
Measure the resistance of the 5-volt Supply circuit between the ECM
C2 harness connector and the Transmission Solenoid Assembly con-
nector internal to the transmission.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 10
No>>
Repair or replace the 5-volt Supply circuit for an open inter-
nal to the transmission.
Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 48RE - STANDARD PROCEDURE)
10.CHECK THE ENGINE CONTROL MODULE - 5 VOLT SUPPLY
Reconnect the ECM harness connectors.
Ignition on, engine not running.
Measure the voltage of the 5-volt Supply circuit in the Governor Pres-
sure Sensor connector internal to the transmission.
Is the voltage between 4.5 and 5.5 volts?
Ye s>>
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 PROCEDURE)
No>>
Using the schematics as a guide, check the Engine Control
Module (ECM) pins, terminals, and connectors for corrosion,
damage, or terminal push out. Pay particular attention to all
power and ground circuits. If no problems are found,
replace and program the ECM per the Service Information.
(Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/ENGINE CONTROL MODULE - REMOVAL)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
Page 3764 of 5267
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?
Ye s>>
Repair as necessary.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Te s t C o m p l e t e .
Page 3765 of 5267
P1762-GOV PRESS SENSOR OFFSET VOLTS TOO LOW OR HIGH (DIESEL)
For a complete wiring diagramRefer to Section 8W
Page 3766 of 5267

Theory of Operation
The Governor Pressure Sensors output is used as a control input to the Governor Pressure Control System. The
Governor Pressure Control System is used to regulate the governor pressure which controls the shifts for first, sec-
ond, and third gear.
When Monitored:
While the engine is running and the vehicle gear selector is in park or neutral for more than 3.0 seconds with
the throttle position less than 10%.
Set Condition:
This DTC will set if the Governor Pressure is greater than 3 psi while the vehicle is in Park 3 times in a drive
cycle.
Possible Causes
OTHER TRANSMISSION DTCS PRESENT
5 VOLT SUPPLY CIRCUIT OPEN - EXTERNAL
5 VOLT SUPPLY CIRCUIT OPEN - INTERNAL
GOVERNOR PRESSURE SENSOR
TRANSMISSION - INTERNAL DAMAGE
TRANSMISSION - INTERNAL LEAK
ENGINE CONTROL MODULE
INTERMITTENT WIRING AND CONNECTORS
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
Diagnostic Test
1.OTHER TRANSMISSION DTCS PRESENT
Ignition on, engine not running.
With the scan tool, read Engine DTCs.
Are any other transmission DTCs present?
Ye s>>
Refer to the Transmission category and perform the appropriate symptom(s).
No>>
Go To 2
2.CHECK IF THE GOVERNOR PRESSURE IS ABOVE 21 KPA (3 PSI) IN PARK
CAUTION: Apply the parking brake.
Start the engine and allow the engine to idle.
Warm the transmission to a normal operating temperature above 43° C (110° F).
With the scan tool in Sensors, read the Governor Pressure with the Transmission Shift selector in Park.
Is the Governor Pressure reading on the scan tool above 21 kPa or 3 psi?
Ye s>>
Go To 3
No>>
Go To 10
Page 3767 of 5267

3.COMPARE SCAN TOOL GOVERNOR PRESSURE READING TO PRESSURE GAUGE READING
Turn the ignition off to the lock position.
Connect a 700 kPa (100 psi) Pressure Gauge to the Governor Pressure test port. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - DIAGNOSIS AND TESTING)
Start the engine and allow the engine to idle.
Warm the transmission to a normal operating temperature above 43° C (110° F).
With the scan tool, read the Governor Pressure and compare the scan tool Governor Pressure reading to the Pres-
sure Gauge reading.
Does the scan tool Governor Pressure reading match the Pressure Gauge reading within 6.9 kPa (1
psi)?
Ye s>>
Go To 4
No>>
Go To 7
4.TRANSMISSION - INTERNAL DAMAGE
Turn the ignition off to the lock position.
Remove the transmission oil pan per the Service Information. (Refer to 21 -TRANSMISSION/TRANSAXLE/AUTO-
MATIC - 48RE/FLUID - STANDARD PROCEDURE)
Inspect the transmission oil pan for burnt oil and/or excessive debris.
Does the transmission contain burnt oil and/or excessive debris?
Ye s>>
Repair internal transmission as necessary. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC -
48RE - REMOVAL)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Go To 5
5.CHECK INTERNAL TRANSMISSION FOR A FLUID LEAK
Inspect the transmission for internal fluid leakage in the Valve Body or the Governor Pressure Solenoid. (Refer to 21
- TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE/VALVE BODY - REMOVAL)
Were there any problems found?
Ye s>>
Repair the internal transmission as necessary per the Service Information. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 48RE/VALVE BODY - REMOVAL)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Go To 6
6.VERIFY OPERATION - TEST DRIVE
Remove the pressure gauge from the transmission.
Install the transmission oil pan and refill the transmission per the Service Information. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 48RE/FLUID - STANDARD PROCEDURE)
With the scan tool, erase Engine DTCs.
Test drive the vehicle.
Be sure to stop the vehicle and move the gear selector into the park positionfor a minimum of 5 seconds at least
three times during the drive cycle.
With the scan tool, read Engine DTCs.
Did the DTC reset?
Ye s>>
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 attentiontoallpowerandgroundcir-
Page 3768 of 5267

cuits. If no problems are found, replace and program the ECM per the ServiceInformation. (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)
No>>
Go To 10
7.CHECK THE 5 VOLT SUPPLY CIRCUIT FOR AN OPEN
Turn the ignition off to the lock position.
Disconnect the ECM C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
NOTE: Check connectors - Clean/repair as necessary
Measure the resistance of the 5-volt Supply circuit between the Trans-
mission Solenoid Assembly harness connector and the ECM C2 har-
ness connector.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 8
No>>
Repair 5-volt Supply circuit for an open.
Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 48RE - STANDARD PROCEDURE)
8.CHECK THE 5 VOLT SUPPLY CIRCUIT FOR AN OPEN - INTERNAL
Reconnect the Transmission Solenoid Assembly harness connector.
Remove the Transmission Oil Pan perthe Service Information. (Refer to
21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE/FLUID -
STANDARD PROCEDURE)
Disconnect the Governor Pressure Sensor harness connector internal to
the transmission.
NOTE: Check connectors - Clean/repair as necessary
Measure the resistance of the 5-volt Supply circuit between the ECM
C2 harness connector and the Governor Pressure Sensor connector
internal to the transmission.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 9
No>>
Repair or replace the 5-volt Supply circuit for an open inter-
nal to the transmission.
Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 48RE - STANDARD PROCEDURE)