Circuit Description
The body control module (BCM) uses a key in ignition input in order to control certain features in the vehicle. These features are in the following systems:
| • | Content Theft Deterrent (if equipped) |
| • | Audible Warnings |
| • | Automatic Door Locks |
The key in ignition input circuit is grounded when you fully insert the ignition key into the ignition switch. This in turn pulls the BCM key in ignition input low.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
| • | The ignition 0 input is active and the key in ignition input is inactive and the signal circuit is high. |
| • | The conditions above must be present for more than 0.3 seconds. |
Action Taken When the DTC Sets
The BCM stores DTC B2964 in memory.
Conditions for Clearing the DTC
| • | The DTC becomes history when the fault is no longer present. |
| • | A history DTC clears after 100 consecutive ignition cycles when the condition for the malfunction is no longer present. |
| • | The BCM receives the clear code command from the scan tool. |
Step | Action | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Audible Warnings Schematics | |||||||||
1 | Did you perform the Audible Warnings Diagnostic System Check? | Go to Step 2 | |||||||
2 |
Does the Key in Ignition parameter display Active? | Go to Step 3 | Go to Step 5 | ||||||
3 |
Does the test lamp illuminate? | Go to Step 4 | Go to Step 8 | ||||||
4 | Test the ignition 0 voltage circuit for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 7 | ||||||
5 | Test the key in ignition switch signal circuit for the following:
Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 6 | ||||||
6 | Test the ground circuit of the ignition key alarm switch for an open or a high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 7 | ||||||
7 | Inspect for poor connections at the harness connector of the ignition switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 9 | ||||||
8 | Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 10 | ||||||
9 | Replace the ignition switch. Refer to Ignition and Start Switch Replacement . Did you complete the replacement? | Go to Step 11 | -- | ||||||
10 |
Important: Program the replacement BCM. Replace the BCM. Refer to Body Control Module Replacement in Body Control Systems. Did you complete the replacement? | Go to Step 11 | -- | ||||||
11 |
Does the DTC reset? | Go to Step 2 | System OK | ||||||
