Test Description
The numbers below refer to the step numbers on the diagnostic table.
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Tests if ground is constantly being applied to the horn relay.
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The horn relay control circuit includes the horn slip ring and the horn switches. The horn slip ring and the horn switches must be tested for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you review the Horns operation and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Horns |
2 | Depress and release the horn switch. Is the horn on at all times? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
3 | Is the vehicle equipped with theft deterrent (UA6)? | Go to Step 4 | Go to Step 5 |
4 | Disconnect the body control module (BCM). Is the horn on at all times? | Go to Step 5 | Go to Step 9 |
5 | Disconnect the horn relay. Is the horn on at all times? | Go to Step 10 | Go to Step 6 |
Connect a test lamp between the battery positive voltage circuit of the horn relay coil and the horn relay control circuit. Does the test lamp illuminate? | Go to Step 8 | Go to Step 7 | |
7 | Inspect for poor connections at the horn relay. 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 13 | Go to Step 12 |
To disable the SIR system, refer to Disabling the SIR System in SIR. Repair the short to ground in the horn relay control circuit. The horn relay control circuit includes the horn slip ring and the horn switches. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 13 | -- | |
9 | Inspect for poor connections at the BCM. 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 13 | Go to Step 11 |
10 | Repair the short to voltage in the horn control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 13 | -- |
11 |
Important: Perform the BCM programming procedure when replacing the BCM. Replace the BCM. Refer to Body Control Module Replacement in Body Control System. Did you complete the replacement? | Go to Step 13 | -- |
12 | Replace the horn relay. Did you complete the replacement? | Go to Step 13 | -- |
13 | Operate the horn. Does the horn operate properly? | System OK | Go to Step 1 |
