Symptom Troubleshooting

Trans/Driveline

Real Time AWD Symptom Troubleshooting - Abnormal noise

Abnormal noise

NOTE:
* Before you troubleshoot, review the how to troubleshoot the real time AWD system.
* If necessary, comparison the noise with a known-good vehicle of the same type, if the noise is remarkably abnormal, do the following troubleshooting.

1. Problem verification 1 (abnormal noise check):

-1. Test-drive the vehicle and check for abnormal noise.

Did abnormal noise reappear?
-YES- Go to step 2.
-NO- Check the following items.
* Check the rear differential fluid level and the fluid condition.
* Check for rear differential fluid leaks.
* Check for interference with items such as the harness.
* Rotate either rear wheel by hand, and check that the other wheel rotates.
* Do the Oil Pressure Control Test in the Functional Test Menu with the HDS Rear Differential Pressure Test.
* Do the rear differential fluid pressure sensor test Rear Differential Fluid Pressure Sensor Test.

2. Rear differential visual check:

-1. Check the following items.
* Check the rear differential fluid level and the fluid condition.
* Check for rear differential fluid leaks.
* Check the interference such as the harness.

Is the check result OK?
-YES- Go to step 3.
-NO- Replace the rear differential fluid or add recommended fluid Rear Differential Fluid Replacement (KA, KC Models AWD).

3. Problem verification (rear differential companion flange rotate check):

-1. Release the parking brake.

-2. Shift the transmission to N.

-3. Raise the vehicle on a lift.

-4. Make a reference mark (A) across the propeller shaft and the rear companion flange.






-5. Remove the propeller shaft mounting bolts from the rear differential companion flange.

-6. Rotate the companion flange by hand.

Can the rear differential companion flange be rotated smoothly by hand?
-YES- Go to step 4.
-NO- Replace the torque control differential (TCD) assembly or the differential carrier assembly Rear Differential Disassembly And Reassembly (KA, KC Models AWD).

4. Rear differential operation check:

-1. Rotate either rear wheel by hand, and check that the other wheel rotates.

Does the other wheel rotate?
-YES- Go to step 5.
-NO- Replace the differential carrier assembly Rear Differential Disassembly And Reassembly (KA, KC Models AWD).

5. Torque control differential (TCD) assembly check:

-1. Realign the reference mark (A) on the propeller shaft and the rear differential companion flange, then install new flange bolts (B).






-2. Remove the following fuse.






-3. Test-drive the vehicle on the lift.

Is the abnormal noise still present?
-YES- Replace the torque control differential (TCD) assembly Rear Differential Disassembly And Reassembly (KA, KC Models AWD).
-NO- Go to step 6.

6. Rear differential solenoid valve check:

-1. Do the SOLENOID TEST LEVEL 7, and then do SOLENOID TEST LEVEL 1 with the HDS.

Did abnormal noise happen when testing LEVEL 7 to LEVEL 1?
-YES- Replace the rear differential solenoid valve Rear Differential Disassembly And Reassembly (KA, KC Models AWD).
-NO- Go to step 7.

7. Rear differential pump motor check:

-1. Do the Air Bleeding in the Adjustment Menu with the HDS.

-2. Listen for any abnormal noise coming from the rear differential pump motor.

Did abnormal noise happen while doing Air Bleeding?
-YES- Replace the rear differential pump motor Rear Differential Pump Motor Removal And Installation (KA, KC Models AWD).
-NO- Go to step 8.

8. Problem verification 2 (abnormal noise check):

-1. Replace the rear differential fluid Rear Differential Fluid Replacement (KA, KC Models AWD).

-2. Do the Air Bleeding in the Adjustment Menu with the HDS.

-3. Test-drive the vehicle on the lift.

Did abnormal noise reappear?
-YES- Replace the torque control differential (TCD) assembly or the differential carrier assembly Rear Differential Disassembly And Reassembly (KA, KC Models AWD).
-NO- Intermittent failure, the system is OK at this time.