Diagnostic Routine C

Diagnostic Routine C

Diagnostic Overview

P188B

Refer to Wiring Diagram Set 34 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

The AWD (All-Wheel Drive) relay module outputs a high current PWM (Pulse-Width Modulation) signal to the ATC (Active Torque Coupling) solenoid voltage supply circuit which increases as torque demand from the PCM (Powertrain Control Module) increases.

DTC Fault Trigger Conditions






Visual Inspection and Diagnostic Pre-checks

- Damaged wiring or ATC (Active Torque Coupling) solenoid

Pinpoint Test

1. CHECK THE ATC (Active Torque Coupling) SOLENOID AND CONTROL CIRCUITS FOR AN OPEN WITH THE ATC (Active Torque Coupling) SOLENOID CONNECTED

1. Ignition OFF.

2. Disconnect: AWD (All-Wheel Drive) Relay Module.

3. Measure:





Is the resistance less than 10 ohms?






2. CHECK THE ATC (Active Torque Coupling) SOLENOID CONTROL CIRCUITS FOR AN OPEN

1. Disconnect: ATC (Active Torque Coupling) Solenoid.

2. Measure:





Are the resistances less than 3 ohms?






3. CHECK THE ATC (Active Torque Coupling) SOLENOID CONTROL CIRCUITS FOR A SHORT TO VOLTAGE

1. Disconnect: ATC (Active Torque Coupling) Solenoid.

2. Ignition ON.

3. Measure:





Is any voltage present?






4. CHECK THE ATC (Active Torque Coupling) SOLENOID CONTROL CIRCUITS FOR A SHORT TO GROUND

1. Ignition OFF.

2. Measure:





Are the resistances greater than 10,000 ohms?






5. CHECK THE ATC (Active Torque Coupling) SOLENOID CONTROL CIRCUITS FOR A SHORT TOGETHER

1. Measure:





Is the resistance greater than 10,000 ohms?






6. CHECK FOR CORRECT AWD (All-Wheel Drive) RELAY MODULE OPERATION

1. Ignition OFF.

2. Disconnect and inspect all PCM (Powertrain Control Module) connectors and the AWD (All-Wheel Drive) relay module connector.

3. Repair:

- corrosion (install new connector or terminals- clean module pins)
- damaged or bent pins- install new terminals/pins
- pushed-out pins- install new pins as necessary

4. Reconnect the PCM (Powertrain Control Module) connectors and the AWD (All-Wheel Drive) relay module connector. Make sure they seat and latch correctly.

5. Operate the system and determine if the concern is still present.

Is the concern still present?