Possible Causes

Fuse(s)
Circuit (Y/R) open
Circuit (L/W) open
Circuit (B/GY) open
Circuit (B/W) open
Horn
Clockspring
Horn switch (part of the steering wheel)
SJB

CAUTION:

Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapters) may damage the connector.

HORN IS INOPERATIVE - PINPOINT TEST REFERENCE

PINPOINT TEST 1		THE HORN IS INOPERATIVE
STEP	INSPECTION		ACTION
1	CHECK THE VOLTAGE TO THE HORN Disconnect: Horn 0922-201. Measure the voltage between the horn 0922-201 pin 1, circuit (L/W), harness side and ground with the horn switch pressed. Is the voltage greater than 10 volts?	Yes	Go to next step.
1		No	Verify the SJB fuse 13 (15A) is OK. If OK, go to step 3.
2	CHECK CIRCUIT (B/GY) FOR AN OPEN Measure the resistance between the horn 0922-201 pin 2, circuit (B/GY), harness side and ground. Is the resistance less than 5 ohms?	Yes	Install a new horn. see HORN . Test the system for normal operation.
2		No	Repair the circuit. Test the system for normal operation.
3	BYPASS THE SJB Connect: Horn 0922-201. Disconnect: SJB J-2280a. Connect a fused (15A) jumper wire between the SJB J-2280a pin 30, circuit (L/W), harness side and between the SJB J-2280a pin 32, circuit (GY/R), harness side. Does the horn sound?	Yes	Go to next step.
3		No	Verify the battery junction box (BJB) fuse 5 (50A) is OK. If OK, Repair circuit (L/W). Test the system for normal operation.
4	CHECK CIRCUIT (Y/R) AT THE SJB FOR AN OPEN Disconnect: SJB J-2280d. Measure the resistance between the SJB J-2280d pin 12, circuit (Y/R), harness side and ground while pressing and releasing the horn switch. Is the resistance less than 5 ohms with the switch pressed and greater than 10,000 with the switch released?	Yes	Go to step 7.
4		No	Go to next step.
5	CHECK CIRCUIT (Y/R) FOR AN OPEN Key in OFF position. Remove the driver air bag module. See DRIVER AIR BAG MODULE , . Disconnect: Clockspring 0922-202a. Measure the resistance between the clockspring 0922-202a pin 2, circuit (Y/R), harness side and the SJB J-2280d pin 12, circuit (Y/R), harness side. Is the resistance less than 5 ohms?	Yes	Go to next step.
5		No	Repair the circuit. Install the driver air bag module. See DRIVER AIR BAG MODULE , . Test the system for normal operation.
6	CHECK THE CLOCKSPRING FOR AN OPEN Key in OFF position. Disconnect: Upper clockspring connector. Measure the resistance between the clockspring 0922-202a pin 5, circuit (B/W), component side and the upper clockspring pin 1, component side; and between the clockspring 0922-202a pin 2, circuit (Y/R), component side and the upper clockspring pin 5, component side. Are the resistances less than 5 ohms?	Yes	Install a new steering wheel. See STEERING WHEEL , . Test the system for normal operation.
6		No	Install a new clockspring. See CLOCKSPRING , . Test the system for normal operation.
7	CHECK THE SJB OPERATION Disconnect all the SJB connectors. Check for: corrosion damaged pins pushed out pins Connect all the SJB connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present?	Yes	Install a new SJB. See SMART JUNCTION BOX (SJB) , . Test the system for normal operation.
7		No	The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.