Deviation Pressure High

Control System DTCs

DTC Troubleshooting: C1858-73

DTC C1858-73 : Differential Fluid Pressure Deviation High

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

1. Problem verification (function test with HDS):

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

-2. Do the Oil Pressure Control Test in the Functional Test Menu with the HDS Rear Differential Pressure Test.

Is the test result OK?
-Fault code is not indicated- Intermittent failure, the system is OK at this time.
-Fault code 4-1 or 6-1 is indicated- Replace the rear differential fluid Rear Differential Fluid Replacement (KA, KC Models AWD), then do the rear differential solenoid valve test Testing and Inspection. If it is OK, replace the rear differential assembly.
-Fault code except 4 -1 and 6 -1 is indicated- Go to step 2.

2. DTC check:

-1. Do the Oil Pressure Control Test in the Functional Test Menu with the HDS Rear Differential Pressure Test three times.

-2. Check for DTCs with the HDS.

Are there any DTCs?
-YES- Go to the indicated DTC's troubleshooting.
-NO- System is OK at this time.