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Test A: The Horn Is Inoperative

PINPOINT TEST A: THE HORN IS INOPERATIVE


A1-A4:






A4-A6:






A7-A10:






A10-A12:






A13-A14:






Normal Operation
The horn switch is grounded through the clockspring by circuit 31-GJ1 (BK/BU). The clockspring provides this ground signal to the instrument cluster through the horn switch on circuit 10-GJ9 (GY/OG). The horn relay control and switched voltage circuits are supplied by the auxiliary junction box (AJB) fuse 4 (20A) through circuit 30-GJ7 (RD/BU). The horn relay ground is controlled by the front electronic module (FEM) through circuit 91S-GJ7 (BN/RD). When the horn switch is pressed, the instrument cluster sends the FEM a command signal over the communication network to ground the horn relay. The FEM supplies a ground, energizing the horn relay and supplying voltage to the horn through circuit 30S-GJ6 (RD/YE).

Possible Causes
- fuse(s)
- circuit 10-GJ9 (GY/OG) open
- circuit 30-GJ7A (RD/BU) open
- circuit 30-GJ7B (RD/BU) open
- circuit 30S-GJ6 (RD/YE) open
- circuit 31-GJ1 (BK/BU) open
- circuit 31-GJ6 (BK/YE) open
- circuit 91S-GJ7 (BN/RD) open
- horn relay
- horn switch
- horn
- clockspring
- FEM
- instrument cluster