Circuit Description
The transfer case shift control module controls the transfer case lock solenoid. The transfer case lock solenoid is released by being energized. This is accomplished by grounding the lock solenoid control circuit during gears shifts, and in the AUTO 4WD mode. Locking action is applied when power or ground are taken away from the lock solenoid, the transfer case motor is prevented from moving. The system is capable of providing a 2HI, 4HI and 4LO lock-up without the need of additional vehicle power to hold the transfer case in these positions. This DTC detects a lock solenoid that is mechanically unable to hold when in the locked state.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC C0326 08: Transfer Case Lock System Performance Signal InvalidConditions for Running the DTC
| • | The ignition is ON. |
| • | The system voltage is 9-18 volts. |
Conditions for Setting the DTC
The transfer case shift control module tries to apply the lock by removing the ground to the lock control circuit, if the transfer case shift control module indicates any movement while locked this DTC will set.
Action Taken When the DTC Sets
| • | All shifting is disabled. |
| • | The SERVICE 4WD indicator remains illuminated for the remainder of the current ignition cycle. |
| • | The transfer case shift control module will command a default shift to 2 high and disable all further shift requests. |
Conditions for Clearing the DTC
| • | The transfer case shift control module will clear the DTC if the condition for setting the DTC is not currently present. |
| • | A history DTC will clear after 100 consecutive ignition cycles without a fault present. |
| • | History DTCs can be cleared using a scan tool. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Transfer Case Control Schematics Connector End View Reference: Transfer Case Control Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
|
Important: If DTC C0321 is set diagnose this DTC before proceeding with DTC C0326 as DTC C0321 may cause this DTC to set falsely. Reprogram the transfer case shift control module. Refer to Control Module References for replacement, setup, and programming. Perform the Clutch Reset Procedure. Refer to Transfer Case High/Low Clutch Reset . Did you complete the repair? | Go to Step 3 | -- | |
3 |
Does the DTC set? | Go to Step 2 | System OK |
