Pinpoint Test I: LFC 16/DTC B2290 - Occupant Classification System (OCS) Fault

WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: When installing a new restraints control module (RCM), always make sure the correct RCM is being installed. The RCM 40-pin connector is keyed differently for vehicles with safety canopies and side air bags than the 40-pin connector for vehicles without safety canopies and side air bags. Do not force the 40-pin connector onto the RCM. If the connector is forced onto the RCM, damage to the RCM and/or connector will occur.

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

I1 CHECK FOR CONTINUOUS OR ON-DEMAND DTCs
WARNING:
1. 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.
2. Do not handle, move or change the original horizontal mounting position of the restraints control module (RCM) while the RCM is connected and the ignition switch is ON. Failure to follow these instructions may result in the inadvertent deployment of the safety canopy and risk of personal injury.
3. Never probe the connectors on the air bag module. Doing so can result in air bag deployment, which can result in personal injury.
4. 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.
5. Never probe the electrical connector on a safety canopy module. Doing so can result in safety canopy deployment.
NOTE:
1. If a seat equipped with a supplemental restraint system (SRS) component is being serviced, the SRS must be depowered.
2. After diagnosing or repairing an SRS, the restraint system diagnostic tools must be removed before operating the vehicle over the road .
3. The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
4. To identify between a production OCS system and a service OCS system (OCS service kit) inspect the OCS ECU electrical connector. A production OCS system allows the disconnect of the electrical connector from the OCS ECU. A service OCS system (OCS service kit) has the OCS ECU electrical connector glued to the ECU, it cannot and should not be disconnected or altered.
5. Mounting and orientation of the OCS ECU is critical for proper system operation. Failure to correctly position and securely fasten the OCS ECU in place can set a diagnostic trouble code (DTC) in the restraints control module (RCM). If the vehicle has been in a collision in which the passenger seat may have been damaged, inspect the OCS ECU mounting area for deformation. If damaged, a new OCS service kit must be installed. In addition, make sure the mounting area of the OCS system is restored to the original production configuration (replace as necessary).
- Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
- Enter the following diagnostic mode on the scan tool: Flag DTC B2290/Record All Flagged Faults.
- Enter the following diagnostic mode on the scan tool: Retrieve/Flag/Record Continuous DTCs.
- Was DTC B2290 retrieved during the on-demand self test?
Yes: This is a hard fault. The fault condition is still present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test.

Using the flagged faults recorded in step I1, GO to the appropriated pinpoint test step.

If a flagged fault of "?" was recorded, multiple faults exist and the entire pinpoint test must be carried out.

Vehicles with a production OCS system

For OCS system with a communications fault, GO to I2.

For OCS system with an internal fault, GO to I19.

For OCS system with a calibration fault, GO to I20.

For OCS system with a pressure sensor fault, GO to I12.

Vehicles with a service OCS system

For OCS system with a communications fault, GO to I2.

For OCS system with an internal fault, GO to I19.

For OCS system with a calibration fault, GO to I20.

For OCS system with a pressure sensor fault, INSTALL a new OCS system service kit. Refer to OCCUPANT CLASSIFICATION SENSOR - SERVICE KIT . GO to I22.

No: This is an intermittent fault. The fault condition is not present at this time. GO to I21.
I2 CHECK THE SEAT WIRING AND CONNECTORS
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Carry out a thorough visual inspection of the OCS system wiring, terminals and connectors, the RCM wiring and terminals and connectors at C2041b pins 17 and 18, and the related seat wiring harness and body wiring harness terminals and connectors.
- Were any problems noted?
Yes: REPAIR the seat connectors and wiring as needed. GO to I22.

No: GO to I3.
I3 CHECK IGNITION CIRCUIT 937 (RD/WH) FOR AN OPEN
- Disconnect: OCS ECU C3285.
- 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 OCS ECU C3285-1, circuit 937 (RD/WH), harness side and ground.
  
  Fig 1: Checking Ignition Circuit 937 (RD/WH) For An Open
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
Yes: GO to I4.

No: REPAIR circuit 937 (RD/WH). GO to I22.
I4 CHECK GROUND CIRCUIT 1203 (BK/LB) FOR AN OPEN
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Measure the resistance between OCS ECU C3285-14, circuit 1203 (BK/LB), harness side and ground.
  
  Fig 2: Checking Ground Circuit 1203 (BK/LB) For An Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
Yes: GO to I5.

No: REPAIR circuit 1203 (BK/LB). GO to I22.
I5 CHECK CIRCUITS 1918 (BN/WH) AND 1919 (PK/OG) FOR A SHORT TO VOLTAGE BETWEEN THE OCS AND THE RCM
- Disconnect: RCM C2041a and C2041b.
- 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 OCS ECU C3285-18, circuit 1918 (BN/WH), harness side and ground; and between OCS ECU C3285-9, circuit 1919 (PK/OG), harness side and ground.
  
  Fig 3: Checking Circuits 1918 (BN/WH) & 1919 (PK/OG) For Short To Voltage Between OCS & RCM
  Courtesy of FORD MOTOR CO.
- Are the voltages less than 0.2 volt?
Yes: GO to I6.

No: REPAIR circuit 1918 (BN/WH) or circuit 1919 (PK/OG). GO to I22.
I6 CHECK CIRCUITS 1918 (BN/WH) AND 1919 (PK/OG) FOR A SHORT TO GROUND BETWEEN THE OCS AND THE RCM
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Measure the resistance between OCS ECU C3285-18, circuit 1918 (BN/WH), harness side and ground; and between OCS ECU C3285-9, circuit 1919 (PK/OG), harness side and ground.
  
  Fig 4: Checking Circuits 1918 (BN/WH) & 1919 (PK/OG) For Short To Ground Between OCS & RCM
  Courtesy of FORD MOTOR CO.
- Are the resistances greater than 1,000,000 ohms?
Yes: GO to I7.

No: REPAIR circuit 1918 (BN/WH) or circuit 1919 (PK/OG). GO to I22.
I7 CHECK CIRCUIT 1918 (BN/WH) FOR AN OPEN BETWEEN THE OCS AND THE RCM
- Measure the resistance between RCM C2041b-17, circuit 1918 (BN/WH), harness side and OCS ECU C3285-18, circuit 1918 (BN/WH), harness side.
  
  Fig 5: Checking Circuit 1918 (BN/WH) For Open Between OCS & RCM
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohm?
Yes: GO to I8.

No: REPAIR circuit 1918 (BN/WH). GO to I22.
I8 CHECK CIRCUIT 1919 (PK/OG) FOR AN OPEN BETWEEN THE OCS AND THE RCM
- Measure the resistance between RCM C2041b-18, circuit 1919 (PK/OG), harness side and OCS ECU C3285-9, circuit 1919 (PK/OG), harness side.
  
  Fig 6: Checking Circuit 1919 (PK/OG) For Open Between OCS & RCM
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohm?
Yes: GO to I9.

No: REPAIR circuit 1919 (PK/OG). GO to I22.
I9 CHECK CIRCUIT 1918 (BN/WH) FOR A SHORT TO CIRCUIT 1919 (PK/OG) BETWEEN THE OCS AND THE RCM
- Measure the resistance between OCS ECU C3285-18, circuit 1918 (BN/WH), harness side and OCS ECU C3285-9, circuit 1919 (PK/OG), harness side.
  
  Fig 7: Checking Circuit 1918 (BN/WH) For Short To Circuit 1919 (PK/OG) Between OCS & RCM
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 1,000,000 ohms?
Yes: GO to I10.

No: REPAIR circuits 1918 (BN/WH) and 1919 (PK/OG). GO to I22.
I10 CHECK THE RCM
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.
- Install a known good RCM. Refer to RESTRAINTS CONTROL MODULE (RCM) .
- Connect: OCS ECU C3285.
- 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 scan tool: On-Demand Self Test.
- Enter the following diagnostic mode on the scan tool: FLAG DTC B2290/Record All Flagged Faults.
- Was DTC B2290 retrieved during the on-demand self test?
Yes: If a flagged fault of "?" was recorded, multiple faults exist and the entire pinpoint test must be carried out.

INSTALL a new OCS service kit. Refer to OCCUPANT CLASSIFICATION SENSOR - SERVICE KIT . GO to I22.

No: Fault corrected. GO to I22.
I11 CHECK THE SEAT WIRING AND CONNECTORS
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Carry out a thorough visual inspection of the OCS system wiring, terminals and connectors and the related seat wiring harness and body wiring harness terminals and connectors.
- Were any problems noted?
Yes: REPAIR the seat connectors and wiring as needed. GO to I22.

No: GO to I12.
I12 CHECK CIRCUITS 1568 (RD/WH), 1569 (GY/LB) AND 1570 (TN/BK) FOR A SHORT TO VOLTAGE
- Disconnect: RCM C2041a and C2041b.
- Disconnect: OCS Pressure Sensor C3042.
- Disconnect: OCS ECU C3285.
- 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 OCS pressure sensor C3042-1, circuit 1568 (RD/WH), harness side and ground; between OCS pressure sensor C3042-2, circuit 1570 (TN/BK), harness side and ground; and between OCS pressure sensor C3042-3, circuit 1569 (GY/LB), harness side and ground.
  
  Fig 8: Checking Circuits 1568 (RD/WH), 1569 (GY/LB) & 1570 (TN/BK) For Short To Ground
  Courtesy of FORD MOTOR CO.
- Are the voltages less than 0.2 volt?
Yes: GO to I13.

No: REPAIR circuit 1568 (RD/WH), circuit 1569 (GY/LB) or circuit 1570 (TN/BK). GO to I22.
I13 CHECK CIRCUITS 1568 (RD/WH), 1569 (GY/LB) AND 1570 (TN/BK) FOR A SHORT TO GROUND
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Measure the resistance between OCS pressure sensor C3042-1, circuit 1568 (RD/WH), harness side and ground; between OCS pressure sensor C3042-2, circuit 1570 (TN/BK), harness side and ground; and between OCS pressure sensor C3042-3, circuit 1569 (GY/LB), harness side and ground.
  
  Fig 9: Checking Circuits 1568 (RD/WH), 1569 (GY/LB) & 1570 (TN/BK) For Short To Ground
  Courtesy of FORD MOTOR CO.
- Are the resistances greater than 1,000,000 ohms?
Yes: GO to I14.

No: REPAIR circuit 1568 (RD/WH), circuit 1569 (GY/LB) or circuit 1570 (TN/BK). GO to I22.
I14 CHECK CIRCUIT 1568 (RD/WH) FOR AN OPEN BETWEEN THE OCS ECU AND PRESSURE SENSOR
- Measure the resistance between OCS ECU C3285-3, circuit 1568 (RD/WH), harness side and OCS pressure sensor C3042-1, circuit 1568 (RD/WH), harness side.
  
  Fig 10: Checking Circuit 1568 (RD/WH) For Open Between OCS ECU & Pressure Sensor
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohm?
Yes: GO to I15.

No: REPAIR circuit 1568 (RD/WH). GO to I22.
I15 CHECK CIRCUIT 1569 (GY/LB) FOR AN OPEN BETWEEN THE OCS ECU AND PRESSURE SENSOR
- Measure the resistance between OCS ECU C3285-5, circuit 1569 (GY/LB), harness side and OCS pressure sensor C3042-3, circuit 1569 (GY/LB), harness side.
  
  Fig 11: Checking Circuit 1569 (GY/DB) For Open Between OCS ECU & Pressure Sensor
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohm?
Yes: GO to I16.

No: REPAIR circuit 1569 (GY/LB). GO to I22.
I16 CHECK CIRCUIT 1570 (TN/BK) FOR AN OPEN BETWEEN THE OCS ECU AND PRESSURE SENSOR
- Measure the resistance between OCS ECU C3285-4, circuit 1570 (TN/BK), harness side and OCS pressure sensor C3042-2, circuit 1570 (TN/BK), harness side.
  
  Fig 12: Checking Circuit 1570 (TN/BK) For Open Between OCS ECU & Pressure Sensor
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohm?
Yes: GO to I17.

No: REPAIR circuit 1570 (TN/BK). GO to I22.
I17 CHECK CIRCUITS 1568 (RD/WH), 1569 (GY/LB) AND 1570 (TN/BK) FOR A SHORT
- Measure the resistance between the OCS pressure sensor:
  - C3042-1, circuit 1568 (RD/WH), harness side and C3042-2, circuit 1570 (TN/BK), harness side.
  - C3042-1, circuit 1568 (RD/WH), harness side and C3042-3, circuit 1569 (GY/LB), harness side.
  - C3042-2, circuit 1570 (TN/BK), harness side and C3042-3, circuit 1569 (GY/LB), harness side.
    
    Fig 13: Checking Circuits 1568 (RD/WH), 1569 (GY/LB) & 1570 (TN/BK) For A Short
    Courtesy of FORD MOTOR CO.
- Are the resistances greater than 1,000,000 ohms?
Yes: GO to I18.

No: REPAIR circuit 1568 (RD/WH), circuit 1569 (GY/LB) and/or circuit 1570 (TN/BK). GO to I22.
I18 CHECK OCS SYSTEM
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.
- Install a new OCS system service kit. Refer to OCCUPANT CLASSIFICATION SENSOR - SERVICE KIT .
- Connect: RCM C2041a and C2041b.
- 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.
- Enter the following diagnostic mode on the scan tool: OCS Rezeroing.
  CAUTION:
  1. It is necessary to rezero the OCS system when a front passenger seat cushion is disassembled, a new trim cover installed, or an OCS service kit is installed. A diagnostic tool is used to trigger the active command to carry out rezeroing of the OCS system.
  2. Make sure the seat is completely assembled before rezeroing.
  3. The following precautions must be taken before rezeroing of the OCS system:
    
    Make sure the OCS system components are connected and no faults are present.
    
    Make sure the OCS system is not at a temperature below 0°C (32°F) or above 45°C (113°F) when initiating the rezeroing process. If the vehicle has been exposed to extreme cold or hot temperatures, the vehicle must be exposed and kept at a temperature within the limits, 0 C to 45°C (32°F to 113°F) for a minimum of 30 minutes.
    
    Make sure nothing is present on the passenger seat before rezeroing and nothing is placed on the seat during the rezeroing process.
    
    Make sure a minimum 8-second time period has passed after cycling the ignition switch ON before the rezeroing process.
  NOTE:
  1. For best results in rezeroing, the OCS system should be at or near room temperature, 10°C to 29°C (50°F to 85°F).
  2. If the first attempt to rezero the OCS system is unsuccessful, a second attempt must be made.
  Using the diagnostic tool, carry out rezeroing of the OCS system.
- Key in OFF position.
  NOTE: The ignition switch must be cycled after rezeroing the OCS system.
- Key in ON position.
- Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
- Enter the following diagnostic mode on the scan tool: Flag DTC B2290/Record All Flagged Faults.
- Was DTC B2290 retrieved during the on-demand self test?
Yes: If a flagged fault of "?" was recorded, multiple faults exist and the entire pinpoint test must be carried out.

INSTALL a new RCM. Refer to RESTRAINTS CONTROL MODULE (RCM) . GO to I22.

No: Fault corrected. GO to I22.
I19 CHECK FOR AN OCS MOUNTING FAULT
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Inspect the OCS ECU for correct mounting location and direction, that the OCS fasteners are tight, there is no damage to the OCS ECU, and no damage to the seat cushion pan.
- Is the OCS ECU correctly located and are the fasteners tight and is there no damage to components?
Yes: INSTALL a new OCS system service kit. Refer to OCCUPANT CLASSIFICATION SENSOR - SERVICE KIT . GO to I22.

No: REPAIR as necessary. Refer to OCCUPANT CLASSIFICATION SENSOR - SERVICE KIT for correct mounting location/direction of the ECU, the correct fasteners for mounting of the ECU. If the seat cushion pan is damaged, refer to the appropriate procedure in SEATING for repair. GO to I22.
I20 CHECK OCS SYSTEM
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.
- Enter the following diagnostic mode on the scan tool: OCS Rezeroing.
  CAUTION:
  1. It is necessary to rezero the OCS system when a front passenger seat cushion is disassembled, a new trim cover installed, or an OCS service kit is installed. A diagnostic tool is used to trigger the active command to carry out rezeroing of the OCS system.
  2. Make sure the seat is completely assembled before rezeroing.
  3. The following precautions must be taken before rezeroing of the OCS system:
    
    Make sure the OCS system components are connected and no faults are present.
    
    Make sure the OCS system is not at a temperature below 0°C (32°F) or above 45°C (113°F) when initiating the rezeroing process. If the vehicle has been exposed to extreme cold or hot temperatures, the vehicle must be exposed and kept at a temperature within the limits, 0 C to 45°C (32°F to 113°F) for a minimum of 30 minutes.
    
    Make sure nothing is present on the passenger seat before rezeroing and nothing is placed on the seat during the rezeroing process.
    
    Make sure a minimum 8-second time period has passed after cycling the ignition switch ON before the rezeroing process.
  NOTE:
  1. For best results in rezeroing, the OCS system should be at or near room temperature, 10°C to 29°C (50°F to 85°F).
  2. If the first attempt to rezero the OCS system is unsuccessful, a second attempt must be made.
  Using the diagnostic tool, carry out rezeroing of the OCS system.
- Key in OFF position.
  NOTE: The ignition switch must be cycled after rezeroing the OCS system.
- Key in ON position.
- Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
- Enter the following diagnostic mode on the scan tool: Flag DTC B2290/Record All Flagged Faults.
- Was DTC B2290 retrieved during the on-demand self test?
Yes: If a flagged fault of "?" was recorded, multiple faults exist and the entire pinpoint test must be carried out.

INSTALL a new OCS system service kit. Refer to OCCUPANT CLASSIFICATION SENSOR - SERVICE KIT . GO to I22.

No: Fault corrected. GO to I22.
I21 CHECK FOR AN INTERMITTENT FAULT
- Key in OFF position.
- Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
- Enter the following diagnostic mode on the scan tool: Flag DTC B2290/Record All Flagged Faults.
- Was DTC B2290 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.

Using the flagged faults, GO to the appropriate pinpoint test step.

If a flagged fault of "?" was recorded, multiple faults exist and the entire pinpoint test must be carried out.

Vehicles with a production OCS system

For OCS system with a communications fault, GO to I2.

For OCS system with an internal fault, GO to I19.

For OCS system with a calibration fault, GO to I20.

For OCS system with a pressure sensor fault, GO to I11.

Vehicles with a service OCS system

For OCS system with a communications fault, GO to I2.

For OCS system with an internal fault, GO to I19.

For OCS system with a calibration fault, GO to I20.

For OCS system with a pressure sensor fault, INSTALL a new OCS system service kit. Refer to OCCUPANT CLASSIFICATION SENSOR - SERVICE KIT . GO to I22.

No: CHECK for causes of the intermittent fault. 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 I22.
I22 CHECK FOR ADDITIONAL DTCs
- Refer to the continuous DTCs recorded during Step I1.
- Were any continuous DTCs retrieved during Step I1 ?
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.