Positive Lead | Measurement / Action | Negative Lead |
|---|---|---|
C218A-4 | Ground |
Is the resistance less than 3 ohms?
Yes | INSTALL a new steering wheel (includes steering wheel wiring harness). REFER to: Steering Wheel (211-04 Steering Column, Removal and Installation). |
|---|---|
No | REPAIR the circuit. |
A14 CHECK THE HORN SWITCH SIGNAL CIRCUIT
Disconnect SCCM C226A. Momentarily connect a fused jumper wire:
Click to display connectors
Positive Lead | Measurement / Action | Negative Lead |
|---|---|---|
C226A-1 | Ground |
Does the horn sound?
Yes | REMOVE the fused jumper wire. GO to A15 |
|---|---|
No | REMOVE the fused jumper wire. REPAIR the open circuit. |
A15 CHECK HORN OPERATION WITH STEERING WHEEL HARNESS ISOLATED
Connect SCCM C226A. Disconnect Clockspring C218B. Momentarily connect a fused jumper wire:
Click to display connectors
Positive Lead | Measurement / Action | Negative Lead |
|---|---|---|
Clockspring C218B, pin 4, component side | Ground |
Does the horn sound?
Yes | REMOVE the fused jumper wire. INSTALL a new steering wheel (includes steering wheel wiring harness). REFER to: Steering Wheel (211-04 Steering Column, Removal and Installation). |
|---|---|
No | REMOVE the fused jumper wire. INSTALL a new clockspring. REFER to: Clockspring (501-20B Supplemental Restraint System, Removal and Installation). TEST the system for normal operation. If the horn is still inoperative, INSTALL a new SCCM. REFER to: Steering Column Control Module (SCCM) (211-05 Steering Wheel and Column Electrical Components, Removal and Installation). |
A16 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
Install the horn relay (if previously removed). Connect Horn C131 or C1102. Reconnect the BCM connectors. Make sure they seat and latch correctly. Operate the system and determine if the concern is still present.
Is the concern still present?
Yes | Click here to access Guided Routine (BCM). |
|---|---|
No | The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues. |
The Horn Is Always On
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.