Control Module Malfunction

Control System DTCs

DTC Troubleshooting: C1851-19

DTC C1851-19 : Control Module Internal Control Module Malfunction

NOTE: Before you troubleshoot, review the how to troubleshoot the real time AWD system.

1. Problem verification (with idling):

-1. Turn the ignition switch to ON (II).

-2. Clear the DTC with the HDS.

-3. Start the engine.

-4. Check for DTCs with the HDS.

Is DTC C1851-19 indicated?
-YES- The failure is duplicated. Update the real time AWD control unit if it does not have the latest software Real Time AWD Control Unit Update, or substitute a known-good real time AWD control unit Service and Repair, and recheck. If the symptom/indication goes away with the updated real time AWD control unit, troubleshooting is complete. If the symptom/indication goes away with a known-good real time AWD control unit, replace the original real time AWD control unit Service and Repair.
-NO- Go to step 2.

2. Problem verification (motor running):

-1. Clear the DTC with the HDS.

-2. With the engine running, do the Air Bleeding in the Adjustment Menu with the HDS Procedures.

-3. Check for DTCs with the HDS.

Is DTC C1851-19 indicated?
-YES- Update the real time AWD control unit if it does not have the latest software Real Time AWD Control Unit Update, or substitute a known-good real time AWD control unit Service and Repair, and recheck. If the symptom/indication goes away with the updated real time AWD control unit, troubleshooting is complete. If the symptom/indication goes away with a known-good real time AWD control unit, replace the original real time AWD control unit Service and Repair.
-NO- Intermittent failure, the system is OK at this time.