C0407
DTC C0407
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC C0407 02
- AWD Oil Pump Motor Short to Ground
DTC C0407 04
- AWD Oil Pump Motor Open
DTC C0407 0B
- AWD Oil Pump Motor High Current
DTC C0407 64
- AWD Oil Pump Motor Component Slipping
Diagnostic Fault Information
Circuit/System Description
The differential clutch pump delivers hydraulic oil pressure to the rear drive clutch solenoid valve and the rear differential clutch solenoid valve. The pump is mounted to the torque transfer device housing. The pressure of the system is calculated by the Rear Differential Clutch Control Module which monitors the differential clutch pump motor current levels. When the calculated pressure reaches approximately 3200 kPa (464 psi), the Rear Differential Clutch Control Module determines that the system pressure has been obtained and deactivates the differential clutch pump. When the calculated pressure drops below approximately 2700 kPa (392 psi), the Rear Differential Clutch Control Module will reactivate the differential clutch pump.
Conditions for Running the DTC
* The ignition is ON.
* Operating temperature range 0-80°C (0-176°F).
Conditions for Setting the DTC
C0407 02
The differential clutch pump current is greater than 9 A in 20 consecutive test cycles. The current will be retested every 30 seconds.
C0407 04
The differential clutch pump current is less than 0.3 A for 30 seconds.
C0407 0B
The differential clutch pump current is greater than 7 A for greater than 2 seconds in 10 consecutive test cycles.
C0407 64
The differential clutch pump current is below a threshold at the end of a pump activation cycle in 30 consecutive test cycles. The measured current is less than 1.5 A from the threshold. The threshold is temperature dependent.
Action Taken When the DTC Sets
* All-wheel drive (AWD) is disabled
* Service Rear Axle is displayed on the driver information center.
Conditions for Clearing the DTC
* The condition for setting the DTC is no longer present.
* The DTC is not detected in 40 consecutive ignition cycles.
Diagnostic Aids
Extreme cold Temperatures, below -18°C (0°F), can cause a DTC C0407 to set. If DTC C0407 sets under these conditions it may be caused by the fluid viscosity and not an electrical malfunction. Before performing the diagnostics allow the differential clutch fluid temperature to rise above 0°C (32°F). If the DTC is no longer set or set in history when above 0°C (32°F) the issue was caused by the fluid viscosity and does not require any electrical repairs. Check for Rear Differential Clutch Control Module calibration updates.
Reference Information
Schematic Reference
Rear Axle Schematics Electrical Diagrams
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Description and Operation
Rear Drive Axle Description and Operation Description
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Verify that DTC C0407 with symptom byte 02, 04 or 0B is not set.
• If DTC C0407 with symptom byte 02, 04 or 0B is set
Refer to Circuit/System Testing.
• If DTC C0407 with symptom byte 02, 04 or 0B is not set
2. Verify the rear axle fluid level is correct. Refer to Rear Axle Lubricant Level Inspection Procedures.
• If the rear axle fluid is below specifications
Inspect for fluid leaks and fill as required.
• If the rear axle fluid is above specifications
1. Verify the differential clutch fluid level is correct. Refer to Differential Clutch Oil Inspection Differential Clutch Oil Inspection.
• If the differential clutch fluid is below specifications, replace the limited slip differential clutch.
• If the differential clutch fluid is above specifications, lower the rear differential clutch fluid to the correct level.
• If the differential clutch fluid level is correct.
2. Lower the rear axle fluid to the correct level.
• If the rear axle lubricant level is correct
Note: The differential clutch assembly must be over filled then lowered to the correct level in order to get a proper fluid level fill and reading.
3. Verify the differential clutch fluid level is correct. Refer to Differential Clutch Oil Inspection Differential Clutch Oil Inspection.
• If the differential clutch fluid is below specifications
Inspect for fluid leaks and fill as required, refer to Differential Clutch Oil Inspection Differential Clutch Oil Inspection.
• If the differential clutch fluid is above specifications
Lower the differential clutch fluid to the correct level.
• If the differential clutch lubricant level is correct
4. Verify that DTC C0407 with symptom byte 64 is not set as current.
• If DTC C0407 with symptom byte 64 is set as current and the differential clutch fluid level is correct
Refer to Circuit/System Testing.
• If DTC C0407 with symptom byte 64 is not set
5. Ignition ON.
6. Verify the Rear Differential Clutch Pump Motor Current parameter is between 2.5-3.5 A when commanding the Rear Differential Clutch Pump Motor ON with a scan tool.
• If not between 2.5-3.5 A
1. Verify there are no system leaks while under pump pressure.
• If the system is leaking, repair as necessary.
• If system is not leaking, replace the M32 Differential Clutch Pump.
• If between 2.5-3.5 A
7. All OK.
Circuit/System Testing
Note: The Q48 Rear Drive Clutch Solenoid Valve is calibrated with and is part of the K47 Rear Differential Clutch Control Module. Both components must be replaced as a matched set.
1. Ignition OFF, disconnect the X2 harness connector at the K47 Rear Differential Clutch Control Module.
2. Test for infinite resistance between the control circuit terminal D and ground.
• If less than infinite resistance
Test or replace the M32 Differential Clutch Pump.
• If infinite resistance
3. Test for 1.5-20 ohms between the control circuit terminal D and the low reference circuit terminal C.
• If not between 1.5-20 ohms
Test or replace the M32 Differential Clutch Pump.
• If between 1.5-20 ohms
4. Replace the K47 Rear Differential Clutch Control Module.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Differential Clutch Pump Replacement Differential Clutch Pump Replacement
* Limited Slip Differential Clutch Replacement Limited Slip Differential Clutch Replacement
* Control Module References Control Module References for Rear Differential Clutch Control Module replacement, programming and setup