2010 Cadillac CTS Sedan AWD V6-3.6L Page 1724
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 P0961
- Line Pressure Control (PC) Solenoid System Performance
DTC P0962
- Line Pressure Control (PC) Solenoid Control Circuit Low Voltage
DTC P0963
- Line Pressure Control (PC) Solenoid Control Circuit High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The line pressure control (PC) solenoid is part of the control solenoid valve assembly which has no serviceable parts. The normally high line PC
solenoid regulates and directs the PC solenoid oil pressure to the isolator/pressure regulator valve. Increasing PC solenoid line pressure increases
transmission line pressure. The TCM varies the current to the line PC solenoid through a low side driver. Decreasing the current to the line PC
solenoid increases line PC solenoid oil pressure by closing OFF the solenoid exhaust port. Increasing the current to the line PC solenoid decreases
line PC oil pressure by opening the solenoid exhaust port. Line PC solenoid power is supplied by the TCM through a high side driver (HSD). The
HSD protects the circuit and components from excessive current flow. If excessive current flow is detected, the HSD will turn OFF. When the fault
is corrected the HSD will reset.
Conditions for Running the DTC
P0961, P0962, or P0963
* The engine speed is greater than 500 RPM for 5 seconds.
* The ignition voltage is 8.6 volts or greater.
* DTCs P0961, P0962 or P0963 are not set.
Conditions for Setting the DTC
P0961
The TCM detects an internal electrical malfunction of the line PC solenoid where the measured line PC solenoid current does not equal the
commanded line PC solenoid current for 5 seconds.
P0962
The TCM detects a short to ground or an open/high resistance on the line PC solenoid control circuit for 1 second.
P0963
The TCM detects a short to voltage on the line PC solenoid control circuit for 1 second.
Action Taken When the DTC Sets
