Pinpoint Test D: LFC18/DTC B1884 - Pad Warning Lamp Circuit Failure

WARNING: This page is about a different car, the 2005 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough Inspection and Verification before proceeding with the pinpoint test.

D1 CHECK FOR A HARD OR INTERMITTENT DTC
WARNING: Restraint system diagnostic tools are for service only. Tools must be removed prior to operating the vehicle over the road. Failure to remove restraint system diagnostic tools could result in injury and possible violation of vehicle safety standards.

WARNING: Never probe the connectors on the air bag module. Doing so can result in air bag deployment, which can result in personal injury.

WARNING: The safety belt pretensioner is a pyrotechnic device. Always wear safety glasses when repairing an air bag equipped vehicle and when handling a safety belt buckle pretensioner or safety belt retractor pretensioner. Never probe a pretensioner electrical connector. Doing so could result in pretensioner or air bag deployment and could result in personal injury.

NOTE: After diagnosing or repairing an SRS, the restraint system diagnostic tools must be removed before operating the vehicle over the road.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
- Enter the following diagnostic mode on the diagnostic tool: On-Demand Self Test.
- Enter the following diagnostic mode on the diagnostic tool: Retrieve/Record Continuous DTCs.
- Was DTC B1884 retrieved during the on-demand self test?
- Yes : If the PAD indicator does illuminate, GO to D2.
  If the PAD indicator does not illuminate, GO to D5.
- No : This is an intermittent fault. The fault condition is not present at this time. GO to D9.
D2 CHECK THE RCM CONNECTOR
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM SRS DEPOWERING AND REPOWERING .
- Disconnect: RCM C310a and C310b.
- Inspect the RCM C310a component side for damaged camming beams.
  
  Fig 1: Inspecting RCM C310a Component Side For Damaged Camming Beams
  Courtesy of FORD MOTOR CO.
- Inspect RCM C310a harness side for worn, damaged or dislodged shorting bar at pins 15 and 16. Inspect for foreign material. Inspect for pushed-out connector terminals.
- Were any RCM connector concerns found?
- Yes : CORRECT the connector concerns. GO to D10.
- No : GO to D3.
D3 CHECK CIRCUIT 608 (BK/YE) FOR SHORT TO GROUND
- Connect: RCM C310a and C310b.
- Disconnect: (PAD) Indicator C2286.
- Measure the resistance between the PAD indicator C2286 pin 3, circuit 608 (BK/YE), harness side and ground.
  
  Fig 3: Measuring Resistance Between PAD Indicator C2286 Pin 3, Circuit 608 (BK/YE), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
- Yes : GO to D8.
- No : GO to D4.
D4 CHECK RCM
- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310a pin 15, circuit 608 (BK/YE), component side and ground.
  
  Fig 4: Measuring Resistance Between RCM C310a Pin 15, Circuit 608 (BK/YE), Component Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
- Yes : REPAIR circuit 608 (BK/YE). GO to D10.
- No : GO to D8.
D5 CHECK PAD INDICATOR
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM SRS DEPOWERING AND REPOWERING .
- Disconnect: RCM C310a and C310b.
- Repower the system. Do not prove out the system at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM SRS DEPOWERING AND REPOWERING .
- Key in ON position.
- Is the PAD indicator on?
- Yes : GO to D8.
- No : GO to D6.
D6 CHECK CIRCUIT 608 (BK/YE) FOR OPEN
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM SRS DEPOWERING AND REPOWERING .
- Disconnect: (PAD) Indicator C2286.
- Measure the resistance between the PAD indicator C2286 pin 3, circuit 608 (BK/YE), harness side and the RCM C310a pin 15, circuit 608 (BK/YE), harness side.
  
  Fig 5: Checking Circuit 608 (BK/YE) For Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohm?
- Yes : GO to D7.
- No : REPAIR circuit 608 (BK/YE). GO to D10.
D7 CHECK CIRCUIT 1003 (GY/YE) FOR OPEN
- Repower the system. Do not prove out the system at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM SRS DEPOWERING AND REPOWERING .
- Key in ON position.
- Measure the voltage between the PAD indicator C2286 pin 1, circuit 1003 (GY/YE), harness side and ground.
  
  Fig 6: Measuring Voltage Between PAD Indicator C2286 Pin 1, Circuit 1003 (GY/YE), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : INSTALL a new PAD indicator. REFER to PASSENGER AIR BAG DEACTIVATION (PAD) INDICATOR . GO to D10.
- No : REPAIR circuit 1003 (GY/YE). GO to D10.
D8 CONFIRM THE RCM FAULT
NOTE: Make sure all restraint system diagnostic tools, sensor electrical connectors and the RCM electrical connector are connected before carrying out the on-demand self test. If not, erroneous DTCs will be recorded.
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM SRS DEPOWERING AND REPOWERING .
- Connect: (PAD) Indicator C2286 (if disconnected in prior step).
- Connect: RCM C310a and C310b (if disconnected in prior step).
- Repower the system. Do not prove out the system at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM SRS DEPOWERING AND REPOWERING .
- Enter the following diagnostic mode on the diagnostic tool: On-Demand Self Test.
- Was DTC B1884 retrieved during the on-demand self test?
- Yes : INSTALL a new RCM. REFER to RESTRAINTS CONTROL MODULE RCM . GO to D9.
- No : CHECK for causes of intermittent open or short to ground on circuit 608 (BK/YE). ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. ACTIVATE other systems in the same wire harness. REPAIR any intermittent concerns found. GO to D10.
D9 CHECK FOR AN INTERMITTENT FAULT
- Key in OFF position.
- Enter the following diagnostic mode on the diagnostic tool: On-Demand Self Test.
- Was DTC B1884 retrieved during the on-demand self test?
- Yes : This is a hard fault. The fault condition is now present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test.
  GO to D2.
- No : CHECK for causes of intermittent open or short to ground on circuit 608 (BK/YE). ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. ACTIVATE other systems in the same wire harness. REPAIR any intermittent concerns found. GO to D10.
D10 CHECK FOR ADDITIONAL DTCs
- Refer to the continuous DTCs recorded during Step D1.
- Were any continuous DTCs retrieved during Step D1 ?
- Yes : Do not clear any DTCs until all DTCs have been resolved. GO to the RESTRAINTS CONTROL MODULE (RCM) DIAGNOSTIC TROUBLE CODE (DTC) TABLE for pinpoint test direction.
- No : RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM SRS DEACTIVATION AND REACTIVATION . REPOWER the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM SRS DEPOWERING AND REPOWERING . PROVE OUT the system. CLEAR all DTCs.