For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Important: Do not use a battery or test light to test the security indicator LED or the LED may be damaged.
1 |

1. Using a DMM set to the diode scale, backprobe the body control module (BCM) connector C3 terminal C16 with the red test lead.
2. Backprobe the BCM connector C3 terminal C1 with the black test lead.

Does the security LED illuminate?

--

Go to Step 2

Go to Step 3

2 |

1. Test for a poor connection at the BCM connector C3 terminal C1 and terminal C16.
2. If the connections are OK, replace the BCM. Refer to Body Control Module Replacement in Body Control Systems.

Is the repair complete?

--

System OK

--

3 |

1. Disconnect the security LED.
2. Connect a test lamp between B+ and terminal A of the security LED harness

Does the test lamp light?

--

Go to Step 4

Go to Step 5

4 |

1. Check for a poor connection in circuit 1376 between the security LED and the BCM.
2. If the Connection is OK, perform the following:

2.1. | Replace the security LED.

2.2. | Disconnect the vehicle battery.

2.3. | Reconnect the vehicle battery.

Is the repair complete?

--

System OK

--

5 | Repair the open in circuit 650 between S217 and the security indicator. Is the repair complete? | -- | System OK | --