For 1990-2009 cars
Body Control Module Components
Body Control System Schematics
Ground Distribution Schematics

### Circuit Description

CKT 80 is the key-in input to the body control module (BCM). The BCM monitors CKT 80 in order to determine if the ignition key is in the ignition switch.

### Conditions for Running the DTC

The ignition switch is on for at least 20 seconds.

### Conditions for Setting the DTC

The KEY-IN IGNITION input to the BCM is not active after the ignition switch has been on for 20 seconds.

### Action Taken When the DTC Sets

• | The BCM assumes the KEY-IN IGNITION input to be active.

• | The interior lights do not turn on when the key is removed from the ignition switch.

### Conditions for Clearing the DTC

• | A current DTC B2965 will clear when the code setting condition is no longer present and the ignition switch is cycled.

• | All BCM history codes clear after 100 ignition cycles (from OFF to ON) with no current codes active during the 100 ignition cycles.

### Diagnostic Aids

• | Inspect the wiring and connections to the ignition switch and BCM.

• | If the DTC is a history DTC, the problem may be intermittent. Perform the tests shown while wiggling the wiring and connectors. This may often cause the malfunction to appear.

### Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. The scan tool will display YES when the ignition key is inserted into the ignition switch.

2. The ignition switch will supply a ground signal to the BCM when the key is inserted.

3. This step tests for a short to ground in circuit 80.

Step | Action | Yes | No
--- | --- | --- | ---
1 | Did you perform the Body Control System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Body Control System
2 |

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. With a scan tool, observe the KEY-IN IGNITION parameter in the BCM data list.

Does the scan tool display YES?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3 |

1. Disconnect the BCM connector C2.
2. Turn ON the ignition, leaving the engine OFF.
3. Use a test lamp connected to battery positive in order to test for a good ground at terminal B12 of connector C2. Refer to Circuit Testing in Wiring Systems.

Is ground present at the terminal?

Go to Step 5

Go to Step 4

4 | Test the following circuits for an open.

• | The ground circuit 151

• | The signal circuit 80

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Was a condition found and corrected?

Go to Step 9

Go to Step 6

5 | Inspect for poor connections at the harness connector of the body control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 7
6 | Inspect for poor connections at the harness connector of the ignition switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 8
7 | Replace the body control module. Refer to Body Control Module Replacement . Important: Perform the set up procedure for the body control module. Refer to Body Control Module (BCM) Programming/RPO Configuration . Did you complete the replacement? | Go to Step 9 | --
8 | Replace the ignition switch. Refer to Ignition and Start Switch Replacement or Ignition and Start Switch Replacement . Did you complete the replacement? | Go to Step 9 | --
9 |

1. Use the scan tool in order to clear the DTCs.
2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK