For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Horns System Check? | -- | Go to Step 2 | Go to Horns System Check
2 | Exchange the horn relay with a known good relay from the underhood wiring harness junction block. Does the horn continue to sound? | -- | Go to Step 3 | Go to Step 4
3 | Disconnect connector C3 from the underhood wiring harness junction block. Does the horn continue to sound? | -- | Go to Step 14 | Go to Step 5
4 | Replace the faulty relay. Is the repair complete? | -- | Go to Horns System Check | --
5 |

1. Reconnect connector C3 to the underhood wiring harness junction block.
2. Disconnect connector C2 of the turn/headlamp switch assembly.

Does the horn continue to sound?

--

Go to Step 6

Go to Step 7

6 | Disconnect the remote control door lock receiver connector. Does the horn continue to sound? | -- | Go to Step 8 | Go to Step 9
7 | Repair a short to ground in the horn switch. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Wheel and Column-Tilt. Is the repair complete? | -- | Go to Horns System Check | --
8 | Disconnect connector C3 of the right IP wiring harness junction block. Does the horn continue to sound? | -- | Go to Step 10 | Go to Step 11
9 | Replace the remote control door lock receiver. Refer to Receiver Replacement in Keyless Entry. Is the repair complete? | -- | Go to Horns System Check | --
10 | Disconnect connector C2 of the right IP wiring harness junction block. Does the horn continue to sound? | -- | Go to Step 12 | Go to Step 13
11 | Repair a short to ground in CKT 28, between the remote control door lock receiver and the right IP wiring harness junction block. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Horns System Check | --
12 | Repair the short to ground in CKT 28, between the underhood wiring harness junction block and the right IP wiring harness junction block or the horn switch. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Horns System Check | --
13 | Replace the right IP wiring harness junction block. Refer to Relay/Fuse Center Replacement in Wiring Systems. Is the repair complete? | -- | Go to Horns System Check | --
14 | Disconnect connector C2 from the underhood wiring harness junction block. Does the horn continue to sound? | -- | Go to Step 15 | Go to Step 16
15 | Repair the short to positive battery voltage in CKT 29, between the underhood wiring harness junction block and the horn assembly. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Horns System Check | --
16 | Replace the underhood wiring harness junction block. Refer to Relay/Fuse Center Replacement in Wiring Systems. Is the repair complete? | -- | Go to Horns System Check | --