2010 Cadillac CTS Sedan AWD V6-3.6L Page 712

2010 Cadillac CTS Sedan AWD V6-3.6L Page 712

4. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the reference circuit terminal 1. With a scan tool, verify the IPC

Rear Differential Temp Sensor parameter is greater than 4.8 V.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the IPC.

5. If all circuits test normal, test or replace the rear differential temperature sensor.

Component Testing

1. Ignition OFF, disconnect the harness connector at the rear differential temperature sensor.

2. Test for 25-10K ohm between the sensor signal terminal 2 and the low reference circuit terminal 1.

瀚慖f not within the specified range, replace the rear differential temperature sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Differential Temperature Sensor Replacement (See: Powertrain Management/Transmission Control Systems/Sensors and Switches -

Transmission and Drivetrain/Sensors and Switches - Differential/Differential Temperature Sensor/Switch/Service and Repair/Differential

Temperature Sensor Replacement)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for IPC replacement, setup, and programming.

C0399

DTC C0399

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 C0399 01

- Clutch Coil Circuit Malfunction Short to Battery

DTC C0399 02

- Clutch Coil Circuit Malfunction Short to Ground

DTC C0399 04

- Clutch Coil Circuit Malfunction Open Circuit

Diagnostic Fault Information

Circuit/System Description

The transfer case normally operates in 2WD mode. When all wheel drive (AWD) is requested, the transfer case control module (TCCM) sends 12

volts to the transfer case clutch coil (TCCC) via the clutch coil control circuit. This engages the transfer case clutch assembly through a ball and

cam apply system. The TCCC is controlled by a high and low side driver. Both circuits must be activated to engage the system.

Conditions for Running the DTC

* The ignition is ON.

* System voltage is between 9 and 16 volts.

Conditions for Setting the DTC