For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Is the vehicle equipped with UA6 (theft deterrent system)? | -- | Go to Step 2 | Go to Step 3
2 | Test the vehicle for body control module DTCs. Refer to Diagnostic Trouble Code (DTC) Displaying in Body Control Systems. Are DTCs present? | -- | Refer to the Diagnostic Trouble Code (DTC) List/Type in Body Control Systems | Go to Step 6
3 |

1. Disconnect the horn relay.
2. Connect a test lamp between horn relay terminal 85 CKT 28 and terminal 86 CKT 740.

Does the test lamp illuminate?

--

Go to Step 4

Go to Step 6

4 |

1. Disconnect the body control module (BCM) connector C2.
2. Connect a test lamp in the same location.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 7

5 | Important: The horn switch is part of the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement in SIR. To disable the SIR system, refer to Disabling the SIR System . Repair the short to ground in CKT 28. (CKT 28 includes the horn slip ring and the horn switch.)

Did you complete the repair?

--

System OK

--

6 |

1. Test for a short to B+ in CKT 29.
2. If CKT 29 is OK, replace the horn relay.

Did you complete the repair?

--

System OK

--

7 | Important: Perform the BCM programming procedure when replacing the BCM. Replace the BCM. Refer to Body Control Module Replacement . Did you complete the repair? | -- | System OK | --