PINPOINT TEST A : The Horn Is Inoperative
- A1 CHECK THE BCM OUTPUT
- Ignition ON.
- Using a scan tool, view BCM PIDs.
- Select the BCM active command PID HORN. Command the horn on and then off.
Does the horn sound when commanded on?
Yes GO to A2. No VERIFY the BCM fuse 22 (20A) is OK. If OK, GO to A8. - A2 CHECK FOR VOLTAGE TO THE SCCM
- Ignition OFF.
- Disconnect: SCCM C2414A .
- Measure:
Positive Lead Measurement / Action Negative Lead C2414A-8 Ground
Is the voltage greater than 11 volts?
Yes GO to A4. No GO to A3. - A3 CHECK THE HORN RELAY COIL GROUND CONTROLLED CIRCUIT FOR AN OPEN
- Disconnect: BCM C2280B .
Is the resistance less than 3 ohms?
Yes GO to A11. No REPAIR the circuit. - A4 CHECK THE CLOCKSPRING GROUND CIRCUIT FOR AN OPEN
- Disconnect: Clockspring C218A .
- Measure:
Positive Lead Measurement / Action Negative Lead C218A-8 Ground
Is the resistance less than 3 ohms?
Yes GO to A5. No REPAIR the circuit. - A5 ISOLATE THE STEERING WHEEL HARNESS
- Connect Clockspring C218A .
- Remove the driver air bag module. REFER to Supplemental Restraint System .
- Disconnect Clockspring C218B .
- Connect the battery ground cable.
- Measure:
Positive Lead Measurement / Action Negative Lead
C218B, pin 4, component side
C218B, pin 10, component side
Is the voltage greater than 11 volts?
Yes REPAIR the steering wheel harness for an open circuit or INSTALL a new steering wheel. REFER to Steering Column . No GO to A6. - A6 CHECK FOR VOLTAGE THROUGH THE CLOCKSPRING
Is the voltage greater than 11 volts?
Yes INSTALL a new clockspring. REFER to Supplemental Restraint System . No GO to A7. - A7 CHECK FOR AN OPEN IN THE CLOCKSPRING
- Remove the clockspring. REFER to Supplemental Restraint System .
- Measure:
Positive Lead Measurement / Action Negative Lead
C218B, pin 4, component side
C218C, pin 1, component side
Is the resistance less than 3 ohms?
Yes GO to A12. No INSTALL a new clockspring. REFER to Supplemental Restraint System . - A8 CHECK FOR VOLTAGE AND GROUND TO THE HORN
- Disconnect Horn C131 .
Is the voltage greater than 11 volts?
Yes INSTALL a new horn. Refer to Horn . No GO to A9. - A9 CHECK FOR VOLTAGE TO THE HORN
- While activating the horn, measure:
Positive Lead Measurement / Action Negative Lead C131-2 Ground
Is the voltage greater than 11 volts?
Yes REPAIR the horn ground circuit for an open. No GO to A10. - While activating the horn, measure:
- A10 CHECK THE BCM HORN OUTPUT CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: BCM C2280E .
Is the resistance less than 3 ohms?
Yes GO to A11. No REPAIR the circuit. - A11 CHECK FOR CORRECT BCM OPERATION
- Disconnect and inspect all 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.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new BCM. REFER to Multifunction Electronic Modules - Without Intelligent Access or REFER to Multifunction Electronic Modules - With Intelligent Access. . 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. - A12 CHECK FOR CORRECT SCCM OPERATION
- Disconnect and inspect all SCCM 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 SCCM 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 CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new SCCM. REFER to Steering Column Switches . 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.



