Normal Operation
The horn relay control voltage and the horn relay switched voltage circuits are supplied by the smart junction box (SJB) fuse 13 (15A) through circuit (GY/R). The horn relay (part of the SJB) is controlled by circuit (Y/R) through the clockspring to the horn switch (part of the steering wheel). When the horn switch is pressed, the horn relay control circuit (Y/R) is grounded through the steering wheel switch harness (part of the steering wheel). The horn relay is then energized causing voltage to be applied to circuit (B/W), enabling the horn to sound. Ground to the horn is supplied through circuit (B/GY).
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Clockspring
- Horn switch (part of the steering wheel)
- SJB
HORN PINPOINT TEST 2
| PINPOINT TEST 2 | THE HORN IS ALWAYS ON | ||
|---|---|---|---|
| STEP | INSPECTION | ACTION | |
| 1 | CHECK THE DTCs FROM THE SJB SELF-TEST
|
Yes | For DTC B1897, Go to step 4. For all other DTCs, Go to 01-01 DIAGNOSTIC TROUBLE CODE (DTC) INDEX - B, C AND U CODES, page 01-01-21. |
| No | Go to next step. | ||
| 2 | CHECK CIRCUIT (L/W) FOR A SHORT TO VOLTAGE
|
Yes | Repair the circuit. Test the system for normal operation. |
| No | Go to next step. | ||
| 3 | CHECK THE SJB FOR INTERNAL FAULTS
|
Yes | Install a new SJB. See SMART JUNCTION BOX (SJB) . Test the system for normal operation. |
| No | Go to next step. | ||
| 4 | CHECK CIRCUIT (Y/R) FOR A SHORT TO GROUND
|
Yes | Repair the circuit. Clear the DTCs. Repeat the self-test. |
| No | Go to next step. | ||
| 5 | CHECK THE CLOCKSPRING FOR A SHORT TO GROUND
|
Yes | Install a new clockspring. See CLOCKSPRING . Test the system for normal operation. |
| No | Install a new steering wheel. See STEERING WHEEL . Test the system for normal operation. | ||