FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

B1C19



B1C19-PASSENGER ACTIVE HEADREST CONTROL CIRCUIT HIGH


Special Tools:











For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Passenger Active Headrest signal circuit is driven by a solenoid that also uses a diode in parallel. The single electrical component of the AHR (Active Headrest) unit is the latch-release solenoid. The solenoid is connected by a 2 way pigtail wire and harness connector. The pigtail wire and 2 way connector are routed through the center of one of the headrest support posts and down through the guide sleeve to the interior of the seat back, where it connects to the seat wire harness. The solenoid is grounded at an independent dedicated ground. The AHR components itself cannot be repaired. If damaged or ineffective, the AHR (Active Headrest) must be replaced as a new assembly. If upon inspection the AHR has deployed it can be reset following the proper reset method. Also if the already deployed Driver or Passenger AHR are latched in the locked position please see the scan tool miscellaneous functions to set the latch in the unlock or deployed position. Please be very observant and careful, the scan tool should never be used to actually deploy a known good non-deployed Driver or Passenger AHR.


- When Monitored:

The Occupant Restraint Controller (ORC) continuously communicates with the Passenger Head Restraint over the Passenger Head Restraint Solenoid Signal circuits. The Passenger Head Restraint communication and on board diagnostics are powered by the ORC signal.

- Set Condition:

This code will set, if the ORC detects High voltage on the (R677) Passenger Head Restraint Solenoid Signal circuit.

Possible Causes:






1. VERIFY ACTIVE DTC

NOTE: Make sure the battery is fully charged.

1. Turn the ignition on.
2. With the scan tool, read the ORC DTCs

Does the scan tool display active B1C19-PASSENGER ACTIVE HEADREST CONTROL CIRCUIT HIGH DTC?

Yes

- Go To 2

No

- Perform the AIRBAG SYSTEM INTERMITTENT TEST. Initial Inspection and Diagnostic Overview.

2. CHECK FOR A SHORTED ACTIVE HEAD REST CIRCUIT IN PASSENGER ACTIVE HEAD REST







WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

1. Access the Passenger Active Head Rest harness connector located in the passenger seatback jumper harness.
2. Disconnect the Passenger Active Headrest harness connectors.

NOTE: Check the connectors - Clean and repair as necessary.

NOTE: Please use the essential tool Active Head Rest Load Tool 10253 in testing the present status of the AHR signal circuit.

3. Connect the AHR Load Tool 10253 to the Passenger AHR seatback jumper harness connector going into the seatback and under the seat.


WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

4. With the scan tool, read the active ORC DTCs.


Does the scan tool display: B1C19-PASSENGER ACTIVE HEADREST CONTROL CIRCUIT HIGH?

Yes

- Go To 3

No

- WARNING: Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
- Replace the Passenger Active Head Rest.


3. CHECK THE (R677) ACTIVE HEAD RESTRAINT 1ST ROW PASSENGER SIGNAL CIRCUIT FOR A SHORT TO BATTERY






WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

1. Disconnect the Passenger Head Restraint harness connector.
2. Connect the ORC harness connectors.
3. Connect the SRS Load Tool Adapter 8443-25 to the ORC harness connectors.

WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

4. Measure the (R677) Passenger Head Restraint Solenoid Signal circuit voltage between the appropriate terminal of the SRS Load Tool Adapter 8443-25 connector and ground.

Is there any voltage present?

Yes

- Repair the (R677) Passenger Head Restraint Solenoid Signal circuit for a short to voltage.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Verification Tests


No

- Go To 4

4. CHECK THE (R677) ACTIVE HEAD RESTRAINT 1ST ROW PASSENGER SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE BETWEEN THE ORC AND THE IN-LINE UNDERSEAT CONNECTOR (BODY HARNESS)






WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

NOTE: Inspect for damaged terminals at the in-line underseat jumper harness connector.

1. Disconnect the in-line underseat harness connector.

WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

2. Measure for voltage between ground and the in-line underseat connector of the (R677) Active Head Restraint 1st Row Passenger Signal circuit at the appropriate terminal of the SRS Load Tool Adapter 8443-25.

Is there voltage present?

Yes

- Repair the short to voltage in the (R677) Active Head Restraint 1st Row Passenger Signal circuit located between the body side of in-line underseat jumper connector and the ORC.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Verification Tests


No

- Go To 5

5. CHECK THE (R677) ACTIVE HEAD RESTRAINT 1ST ROW PASSENGER SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE IN THE SEAT BACK HARNESS






WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

NOTE: Inspect for damaged or bent terminals at the in-line underseat jumper harness connector. Reconnect the in-line harness connector.

1. Connect the in-line under seat connector.
2. Access the Passenger Active Headrest connector located in the passenger seat back jumper harness.
3. Disconnect the Passenger Active Headrest harness connector.

WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

4. Measure the voltage between ground and the (R677) Active Head Restraint 1st Row Passenger Signal circuit at the appropriate terminal of the SRS Load Tool Adapter 8443-25.

Is there voltage present?

Yes

- Repair the short to voltage in the (R677) Active Head Restraint 1st Row Passenger Signal circuit located between the in-line underseat jumper harness connector and the Passenger Active Headrest connector.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Verification Tests


No

- Go To 6

6. CHECK THE (R677) ACTIVE HEAD RESTRAINT 1ST ROW PASSENGER SIGNAL CIRCUIT AN OPEN OR HIGH RESISTANCE BETWEEN THE ORC AND THE IN-LINE BODY SIDE HARNESS UNDERSEAT HARNESS CONNECTOR


WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

1. Disconnect the in-line underseat harness connector.
2. Measure the resistance of the (R677) Active Head Restraint 1st Row Passenger Signal circuit from the inline underseat connector (body harness) to the appropriate terminal of the SRS Load Tool Adapter 8443-25.

Is the resistance below 1 Ohm?

Yes

- Go To 7

No

- Repair the (R677) Active Head Restraint 1st Row Passenger Signal circuit between the ORC and the inline body harness connector for an open or high resistance.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Verification Tests


7. CHECK THE (R677) ACTIVE HEAD RESTRAINT 1ST ROW PASSENGER SIGNAL CIRCUIT FOR AN OPEN OR HIGH RESISTANCE TO THE PASSENGER ACTIVE HEADREST CONNECTOR (SEAT BACK JUMPER HARNESS)






WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

1. Access the Passenger Active Headrest connector located in the passenger seat back.
2. Disconnect the Passenger Active Headrest harness connector.
3. Measure the resistance of the (R677) Active Head Restraint 1st Row Passenger Signal circuit from the appropriate terminal of the Passenger Active Headrest connector to the appropriate terminal of the SRS Load Tool Adapter 8443-25.

Is the resistance below 1 Ohm?

Yes

- Go To 8

No

- Repair the (R677) Active Head Restraint 1st Row Passenger Signal circuit for an open or high resistance.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.


8. CHECK THE PASSENGER ACTIVE HEAD REST (Z914) GROUND CIRCUIT OF THE SEATBACK JUMPER HARNESS FOR AN OPEN






1. Measure the resistance between ground and the (Z914) Ground circuit at the Passenger Active Headrest harness connector (seatback jumper harness side).

Is the resistance below 5.0 Ohms?

Yes

- Go To 9

No

- Repair the Ground circuit for a open or high resistance.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.


9. CHECK THE PASSENGER ACTIVE HEAD REST (Z914) GROUND CIRCUIT TO GROUND FOR AN OPEN OR HIGH RESISTANCE






1. Measure the resistance between ground and the (Z914) Ground circuit at the Passenger Active Headrest harness connector (component side).

Is the resistance below 5 Ohms?

Yes

- Reconnect all previously disconnected components. WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
- Turn the Ignition Off and wait 15 seconds before turning the Ignition On.
- Wait one minute and read active codes.
- If the B1C19-Passenger Active Headrest Control Circuit High DTC becomes active, replace the ORC.

No

- Go To 10

10. CHECK OPERATION OF THE PASSENGER ACTIVE HEAD REST


1. Replace the Passenger Head Restraint.
2. Reconnect the vehicle body harness to the Passenger Head Restraint harness connector.
3. Remove any special tools or jumper wires and reconnect all previously disconnected components - except the Battery.

WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

4. Connect the scan tool to the Data Link Connector - use the most current software available.
5. Use the scan tool and erase the ORC stored codes.
6. Turn the Ignition Off and wait 15 seconds before turning the Ignition On.
7. Wait one minute and read active codes and if there are none present read the stored codes.

Does the scan tool display active B1C19-PASSENGER ACTIVE HEADREST CONTROL CIRCUIT HIGH DTC?

Yes

- WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

- WARNING: If the Occupant Restraint Controller (ORC) is dropped at any time, it must be replaced. Failure to follow these instructions may result in possible serious or fatal injury.

- Replace the ORC.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.

No

- Repair is complete.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.