Circuit Description
The body control module (BCM) monitors the key-in ignition switch on CKT 80 in order to determine if the key is in the ignition switch. This signal provides an audible warning to the driver that the key is still in the ignition switch. The signal provides exit lighting when the key is removed. The BCM will set a DTC B2961 when CKT 80 is shorted to battery voltage or open and the ignition switch has been turned to the RUN position.
Conditions for Setting the DTC
| • | When CKT 80 is open shorted to battery voltage and the ignition switch has been turned to the RUN position. |
| • | The system voltage must be between 9.0-16.0 volts. |
| • | The above conditions must be met for 0.5 seconds. |
Action Taken When the DTC Sets
| • | The key-in warning chime does not operate. |
| • | The exit lighting feature does not operate. |
Conditions for Clearing the MIL/DTC
| • | This DTC will clear immediately after the condition for setting the fault is corrected. |
| • | A history DTC will clear after 100 consecutive ignition cycles without a fault present. |
| • | Use a scan tool in order to clear history and current DTCs. |
Diagnostic Aids
| • | Always diagnose the first DTC listed on the scan tool. |
| • | The scan tool must display DTC B2961 as a current code before performing diagnostics. |
| • | If CKT 80 has been shorted to battery voltage the key-in ignition switch must be inspected for damaged as well as repairing the short to battery. |
| • | Perform a visual inspection for loose or poor connections at all related components. |
| • | Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems for intermittent and poor connections. |
Test Description
Step number(s) below refer to the same step number(s) in the Diagnostic Table.
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This step determines if CKT 80 shorted to battery voltage.
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This step determines if the BCM is defective.
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This tests CKT 80 for an open between the BCM and the key-in ignition switch connector.
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This step determines if CKT 1850 is open between the key-in ignition switch connector and ground or if the key-in ignition switch is open.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the BCM Diagnostic System Check performed? | -- | ||
2 |
Does the DMM display battery voltage? | -- | ||
3 |
Does the KEY IN IGNITION display the specified value? | YES | ||
4 |
Does the DMM display battery voltage? | -- | ||
5 | Connect a test lamp to B+ and probe the key-in ignition switch CKT 1850 (BLK). Does the test lamp light? | -- | ||
6 | Replace the key-in ignition switch. Is the repair complete? | -- | -- | |
7 | Locate and repair the open in CKT 1850 (BLK) from the key-in ignition switch to ground. Is the repair complete? | -- | -- | |
8 | Locate and repair the open in CKT 80 (LT GRN) between the BCM and the key-in ignition switch. Is the repair complete? | -- | -- | |
9 |
Is the repair complete? | -- | -- | |
10 |
Is the repair complete? | -- | System OK | -- |
11 | Clear the DTCs. Refer to Clearing DTCs . Is the repair complete? | -- | System OK | -- |
