Circuit Description
The direct battery supply line (circuit 1640) provides the power to the module and motor circuitry.
This DTC detects a intermittent absence of battery voltage at the module when the module sees an ignition on voltage.
Conditions for Setting the DTC
The transfer case shift control module did not power up 8 out of the last 19 ignition cycles.
Action Taken When the DTC Sets
There are no default actions associated with this DTC. The SERVICE AWD/4WD lamp will not be latched on.
Conditions for Clearing the DTC
| • | Current DTC |
| The transfer case shift control module will clear the DTC if the condition for setting the DTC no longer exists. |
| • | History DTC |
| - | Once 100 consecutive ignition cycles without a fault present. |
| - | You issue a scan tool CLEAR CODES command. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the Transfer Case Diagnostic System Check performed? | -- | ||
2 | Inspect the ATC Fuse in the Underhood Bussed Electrical Center. Is the fuse good? | -- | ||
3 |
Is the fuse good? | -- | ||
4 |
Did the DMM display ever drop below battery voltage? | 9-14 V | ||
5 | Repair a open condition in CKT 1640. Are the repairs complete? | -- | -- | |
6 |
Is the resistance measured ever greater than the specified values? | 0-5 ohms | ||
7 | Repair an open or poor ground condition in CKT 1050. Refer to Wiring Repairs in Electrical Diagnosis. Are the repairs complete? | -- | -- | |
8 | Replace the transfer case shift control module. Refer to Transfer Case Control Module Replacement. Is the action complete? | -- | -- | |
9 |
Is the resistance measured ever less than the specified value? | OL | ||
10 |
Are the repairs complete? | -- | -- | |
11 |
Are the repairs complete? | -- | -- | |
12 | Reconnect all ATC system components, make sure all the components are properly mounted. Have all the ATC components been reconnected and properly mounted? | -- | -- | |
13 | Clear all ATC codes. Have all the ATC codes been cleared? | -- | -- |
