2010 Cadillac CTS Sedan AWD V6-3.0L Page 1674
1. Ignition OFF, disconnect the automatic transmission manual shift switch harness connector.
2. Ignition ON, test for 11-13 volts on terminal H on the automatic transmission manual shift switch harness connector and ground.
瀚慖f not within the specified value, test the ignition voltage circuit for a short to ground or an open/high resistance. If the circuit tests
normal, replace the BCM.
3. Ignition OFF, shift the automatic shift lever into the M position.
4. Ignition OFF, test for 6.6-7.0 k ohm between terminal D and terminal H on the automatic transmission manual shift lever harness connector.
Also test for 3.7-4.2 k ohm when pushing back on the shift lever and 1.7-2.0 k ohm when pushing forward on the shift lever.
瀚慖f not within the specified values, replace the automatic transmission shift lever assembly.
5. Ignition OFF, connect a 3A fused jumper wire between terminal D and terminal H on the automatic transmission manual shift switch harness
connector.
6. Ignition ON, test for 11-13 volts on the BCM connector X1 terminal 20 and ground.
瀚慖f not within the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit test normal, replace
the BCM.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Replace the AT shift program switch. Refer to Transmission Control Replacement (See: Transmission and Drivetrain/Automatic
Transmission/Transaxle/Shifter A/T/Service and Repair/Transmission Control Replacement).
* Replace the body control module. Refer to Control Module References (See: Testing and Inspection/Programming and Relearning) for
replacement, setup, and programming.
P0842
DTC P0842 or P0843
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0842
- Transmission Fluid Pressure (TFP) Switch 1 Circuit Low Voltage
DTC P0843
- Transmission Fluid Pressure (TFP) Switch 1 Circuit High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
