Yes | GO to B4 |
|---|---|
No | GO to B5 |
B4 ISOLATE THE HORN RELAY CONTROL CIRCUIT
Ignition OFF. Disconnect BCM C2280F. Install the horn relay.
Does the test light illuminate?
Yes | REPAIR the short to ground on the horn relay control circuit. |
|---|---|
No | GO to B9 |
B5 ISOLATE THE BCM (BODY CONTROL MODULE) HORN SWITCH INPUT CIRCUIT
Ignition OFF. Install the horn relay. Disconnect BCM C2280B.
Does the test light illuminate?
Yes | GO to B9 |
|---|---|
No | GO to B6 |
B6 CHECK THE HORN SWITCH INPUT CIRCUIT TO THE BCM (BODY CONTROL MODULE) FOR A SHORT TO GROUND
Disconnect SCCM C226A. Connect BCM C2280B.
Does the test light illuminate?
Yes | REPAIR the circuit. |
|---|---|
No | GO to B7 |
B7 ISOLATE THE HORN SWITCH
Remove the driver airbag. REFER to: Driver Airbag (501-20B Supplemental Restraint System, Removal and Installation). Disconnect Clockspring C218B. Connect SCCM C226A.
Does the test light illuminate?
Yes | INSTALL a new clockspring. REFER to: Clockspring (501-20B Supplemental Restraint System, Removal and Installation). TEST the system for normal operation. If the test light remains illuminated, INSTALL a new SCCM. REFER to: Steering Column Control Module (SCCM) (211-05 Steering Wheel and Column Electrical Components, Removal and Installation). |
|---|---|
No | GO to B8 |
B8 ISOLATE THE STEERING WHEEL WIRING
Connect Clockspring C218B.
Does the test light illuminate?
Yes | INSTALL a new steering wheel (includes steering wheel wiring harness). REFER to: Steering Wheel (211-04 Steering Column, Removal and Installation). |
|---|---|
No | INSTALL a new driver airbag (includes horn switch). REFER to: Driver Airbag (501-20B Supplemental Restraint System, Removal and Installation). |
B9 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
Disconnect and inspect the BCM connectors. Repair:
corrosion (install new connector or terminals – clean module pins) damaged or bent pins – install new terminals/pins pushed-out pins – install new pins as necessary
Reconnect the BCM connectors. Make sure they seat and latch correctly. Connect Horn C131 or C1102. Operate the system and determine if the concern is still present.
2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.