Pinpoint tests of the sound signal (Focus 1)

A1: CHECK ELECTRICAL CIRCUIT 29S-GJ1 (ORANGE/BLUE) FOR SHORT TO BATTERY POSITIVE TERMINAL

1Disconnect the Horn Relay.

• Does the buzzer go off when the relay is disconnected?

→ Yes

Go to A2

→ No

REPAIR circuit 29S-GJ1 (orange/blue) for short to battery positive. CHECK system for proper operation.

A2: CHECK ELECTRICAL CIRCUIT 91S-GJ7 (BLACK/BLUE) FOR SHORT CIRCUIT "MASS"

1Using a digital multimeter, measure the resistance between pin 2 of the horn relay, circuit 91S-GJ7 (black/blue), and ground.

• Resistance greater than 10,000 ohms?

→ Yes

INSTALL a new horn relay. CHECK the system for proper operation.

→ No

Go to A3

A3: CHECKING THE HORN SWITCH LOCATED ON THE STEERING WHEEL

1Remove the lower steering column cover.

2Disconnect C896 airbag sliding contact.

3Using a digital multimeter, measure the resistance between pins 1 and 2 of the C896 airbag slider connector, component side.

• Resistance greater than 10,000 ohms?

→ Yes

Install a new relay. CHECK the system for proper operation.

→ No

Go to A4

A4: CHECKING THE HORN SWITCH LOCATED ON THE STEERING WHEEL

WARNING: To properly deactivate the air bag, refer to the procedure in Section 501-20B.

1Remove the airbag. For additional information, refer to Section 501-20A / 501-20B.

2Disconnect the C920 horn switch.

3Using a digital multimeter, measure the resistance between pin 1 and pin 2 of the C920 horn switch connector.

• Resistance greater than 10,000 ohms?

→ Yes

INSTALL a new airbag sliding contact. CHECK the system for proper operation.

→ No

INSTALL new horn switch(es). CHECK system for proper operation.

B1: CHECKING FUSE 7 (40A)

1CHECK Fuse 7 (40A) CJB.

• Is the audio unit functioning properly?

→ Yes

Go to B2

→ No

REPAIR fuse 7. CHECK that the system is operating correctly.

B2: CHECKING FUSE 34 (20A)

1CHECK Fuse 34 (20A) CJB.

• Is the fuse good?

→ Yes

Go to B3

→ No

REPAIR fuse 34. CHECK that the system is operating correctly.

B3: CHECKING THE HORN RELAY

1Disconnect the Horn Relay.

2Perform a relay component test. For more information, refer to Horn Relay in this section..

• Is the relay working properly?

→ Yes

Go to B4

→ No

INSTALL a new horn relay. CHECK the system for proper operation.

B4: CHECKING THE CJB POWER SUPPLY

1Using a digital multimeter, measure the voltage between pin 1 of the horn relay, harness side, and ground, and pin 3 of the horn relay, harness side, and ground.

• Is the voltage greater than 10 V in all cases?

→ Yes

Go to B5

→ No

REPAIR electrical circuit 30-DA1 (red). CHECK for proper system operation.

B5: CHECKING THE POWER SUPPLY OF THE HORN SWITCH

1Connect the Horn Relay.

2Disconnect C896 airbag sliding contact.

3Remove the lower steering column cover.

4Using a digital multimeter, measure the voltage between pin 2 C896 of the airbag wiper, circuit 91S-GJ7 (BLK/BU), harness side, and ground.

• Is the voltage greater than 10 V?

→ Yes

Go to B6

→ No

REPAIR electrical circuit 91S-GJ7 (black/blue), CHECK correct system operation.

B6: CHECKING THE EARTH CIRCUIT OF THE HORN SWITCH

1Using a digital multimeter, measure the resistance between pin 1 C896 of the air bag wiper, circuit 91-PG30 (BK/WH), harness side, and ground.

• Resistance less than 5 Ohm?

→ Yes

Go to B7

→ No

REPAIR electrical circuit 91-PG30 (black/white), CHECK for proper system operation.

B7: CHECKING THE OPERATION OF THE AIR BAG SLIDING CONTACT

1Using a digital multimeter, measure the resistance between pins 1 and 2 of the airbag wiper connector C896, component side. Take readings with the switch pressed and with the switch released.

• Is the resistance greater than 10,000 ohms with the switch not pressed and less than 5 ohms with the switch pressed?

→ Yes

Go to B9

→ No

Go to B8

B8: CHECKING THE HORN SWITCH

WARNING: To properly deactivate the air bag, refer to the procedure in Section 501-20B.

1Remove the airbag. For additional information, refer to Section 501-20A / 501-20B.

2Disconnect C982 horn switch.

3Using a digital multimeter, measure the resistance between pins 1 and 2 of the horn switch connector C982. Take readings with the switch pressed and with the switch released.

• Is the resistance greater than 10,000 ohms with the switch not pressed and less than 5 ohms with the switch pressed?

→ Yes

Install a new airbag sliding contact. CHECK the system for proper operation.

→ No

INSTALL new horn switch(es). CHECK system for proper operation.

B9: CHECKING THE POWER SUPPLY OF THE HORN(S)

1Connect C896 airbag sliding contact.

2Connect the C920 horn switch.

3Disconnect C77 horn.

4Using a digital multimeter, measure the voltage between pin 1 C77 of the horn(s), circuit 29S-GJ1 (orange/blue), harness side, and ground while pressing the horn switch.

• Is the voltage greater than 10 V?

→ Yes

Go to B10

→ No

REPAIR electrical circuit 29S-GJ1 (orange/white). CHECK correct system operation.

B10: CHECKING THE EARTH CIRCUIT OF THE HORN(S)

1Using a digital multimeter, measure the resistance between pin 2 C77 of the horn(s), circuit 31-GJ1 (black), harness side, and ground.

• Resistance less than 5 ohms?

→ Yes

INSTALL new horn(s). CHECK system for proper operation.

→ No

REPAIR electrical circuit 31-GJ1 (black). CHECK for proper system operation.