Seat Occupant Sensor: Service and Repair
OCCUPANT CLASSIFICATION SENSORSpecial Tool(s)
Special Tool(s):
Seat With OEM Occupant Classification Sensor (OCS):
Seat With a Service Kit Occupant Classification Sensor (OCS):
Removal
WARNING:
- Install a new occupant classification sensor (OCS) system service kit as a complete assembly. Never install only part of the kit components. Failure to follow this instruction may result in incorrect operation of the OCS system and increases the risk of serious personal injury or death in a crash.
- Never probe the electrical connectors on air bag, safety canopy or side air curtain modules. Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.
- To reduce the risk of accidental deployment, do not use any memory saver devices. Failure to follow this instruction may result in serious personal injury or death.
CAUTION:
- It is necessary to carry out the occupant classification sensor (OCS) system reset when a front passenger seat backrest is separated from the seat cushion, the seat cushion is disassembled, a new trim cover is installed or an OCS service kit is installed. A scan tool is used to trigger the active command to carry out system reset of the OCS system. Failure to follow these instructions may result in incorrect operation of the OCS system and may cause system failure.
- While positioning the seat cushion frame and occupant classification sensor (OCS) assembly, be careful not to damage any of the components. Failure to do so can result in component failure.
NOTE:
- Occupant classification sensor (OCS) system components (seat cushion foam pad, bladder with pressure sensor and electronic control unit [ECU]) are calibrated to each other and are serviced as an assembly. The OCS system components are not to be installed separately.
- To identify between a production OCS system and a OCS system service kit inspect the ECU electrical connector. A production OCS system allows the disconnect of the ECU electrical connector. An OCS system service kit has the ECU electrical connector glued to the ECU. It cannot and should not be disconnected or altered.
- The heated seat element on the front passenger seat cushion is not serviceable separately. If a new heated seat element is needed on the front passenger seat cushion, a new OCS service kit and a new heated seat element must be installed.
- If a seat equipped with a supplemental restraint system (SRS) component is being serviced, the SRS must be depowered.
- The air bag warning indicator illuminates when the restraints control module (RCM) fuse is removed and the ignition switch is ON. This is normal operation and does not indicate an SRS fault.
- The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
- Repair is made by installing a new part only. If the new part does not correct the condition, install the original part and perform the diagnostic procedure again.
All seats
1. Position the front passenger seat to access the fasteners.
2. Depower the SRS.
3. Remove the front passenger seat.
4. Remove the front seat backrest.
5. Remove the seat track.
Headed Seats
6. Disconnect the cushion heated seat element electrical connector.
Seats with manual recline
7. Remove the seat backrest recliner handle.
Seats with power lumbar
8. Release the tabs at the front and back to separate the power lumbar switch and bezel from the seat cushion pan.
9. Disconnect the electrical connector and remove the power lumbar switch.
All seats
10. Release the remaining seat cushion trim cover J-clips.
11. CAUTION:
- It is necessary to carry out the occupant classification sensor (OCS) system reset when a front passenger seat cushion is disassembled, a new trim cover installed or an OCS service kit is installed. A scan tool is used to trigger the active command to carry out the OCS system reset. Failure to follow these instructions may result in incorrect operation of the OCS system and may cause system failure.
- Use care when separating the seat cushion trim cover from the hook-and-loop strip. The hook-and-loop strip can be torn from the seat cushion foam. Failure to follow this procedure can result in component damage and/or system failure.
Separate the hook-and-loop strips. Position the seat cushion trim cover aside.
12. Bend the retaining tab holding the pressure sensor in place down and aside.
Seats with an original equipment OCS
13. Remove the seat cushion pad from the seat cushion frame.
14. If necessary, remove the 2 pin-type retainers and the mat, otherwise position the mat aside.
15. Remove the ECU and separate the pressure sensor from the ECU bracket.
1 Release the pressure sensor hose.
2 Disconnect the electrical connector and slide the pressure sensor off the bracket.
3 CAUTION: Do not oversize the seat cushion frame holes used to rivet the electronic control unit (ECU) in place. Failure to follow these instructions may result in incorrect operation of the occupant classification sensor (OCS) system and may cause system failure.
Using a 5 mm (3/16 in) drill, remove the 3 rivets.
4 Remove the ECU bracket.
5 Disconnect and remove the ECU.
16. Remove the pin-type retainers holding the occupant classification sensor bladder to the seat cushion pan.
17. NOTE: Make note of the opening that the pressure sensor and hose are being fed through on the seat cushion support assembly for installation purposes.
Separate the OCS bladder and pressure sensor from the seat cushion frame.
- Feed the pressure sensor and hose through the seat cushion support assembly.
Seats with an OCS service kit
18. Separate the OCS components from the seat cushion frame.
1 Release the pressure sensor hose.
2 Slide the pressure sensor off the bracket.
3 Cut the tie straps.
4 CAUTION: Do not oversize the seat cushion frame holes used to rivet the electronic control unit (ECU) in place. Failure to follow these instructions may result in incorrect operation of the occupant classification sensor (OCS) system and may cause system failure.
Using a 5 mm (3/16 in) drill, remove the 3 rivets.
5 Remove the ECU bracket.
6 Disconnect the service part OCS electrical connector.
19. NOTE: Make note of the opening that the OCS components are being fed through on the seat cushion support assembly for installation purposes.
Remove the OCS from the seat cushion frame.
- Feed the hose, pressure sensor, wire harness, electrical connector and ECU through the seat cushion frame support assembly.
20. If necessary, remove the 2 pin-type retainers and the mat.
Installation
All seats
1. Bend the pressure sensor bracket retaining ear back so it will engage upon assembly.
Vehicles with heated seats
2. NOTE: The heated seat element on the front passenger seat cushion is not serviceable separately. If a new heated seat element is needed on the front passenger seat cushion, a new OCS service kit and a new heated seat element must be installed.
Attach the heated seat cushion element to the seat cushion pad.
Seats having the original equipment OCS installed
3. CAUTION: Failure to route the seat occupant classification sensor (OCS) components through the correct seat cushion support opening can cause system failure and incorrect OCS system operation.
Position the OCS assembly to the seat cushion frame.
- Feed the pressure sensor with hose through the largest opening at the front of the seat cushion frame support assembly as noted during removal.
4. Install the pin-type retainers holding the OCS bladder to the seat cushion frame.
5. If the mat was removed, position the mat over the bladder and install pin-type retainers, otherwise position the mat over the bladder.
6. Attach and connect the OCS components.
1 Position the ECU to the seat cushion frame and connect the electrical connector.
2 Install the 2 rivets to hold the ECU in place.
3 Position the ECU bracket through the opening in the front of the seat cushion frame.
4 Install the ECU bracket rivet.
5 Install the pressure sensor onto the seat cushion frame bracket, making sure the retaining ear is completely engaged.
- Connect the pressure sensor electrical connector.
6 Attach the pressure sensor hose.
7. Install the seat cushion pad to the seat cushion frame.
Seats having an OCS service kit installed
8. WARNING: Install a new occupant classification sensor (OCS) system service kit as a complete assembly. Never install only part of the kit components. Failure to follow this instruction may result in incorrect operation of the OCS system and increases the risk of serious personal injury or death in a crash.
CAUTION: Failure to route the seat occupant classification sensor (OCS) components through the correct seat cushion support opening can cause component failure.
NOTE: If the original equipment OCS is not being installed, install a service kit OCS using all parts in the kit.
Position the OCS assembly to the seat cushion frame.
- Using an OCS service kit, feed the ECU, electrical connector, wire harness, pressure sensor and hose through the largest opening at the front of the seat cushion frame support assembly as noted during removal.
- Position the seat cushion pad and bladder to the seat cushion frame.
9. NOTE: When installing a service part OCS, main seat wire harness pressure sensor electrical connector does not get used.
Attach and connect the OCS components.
1 Position the ECU onto the seat cushion frame and install the 2 rivets.
2 Position the ECU bracket through the opening in the front of the seat cushion frame.
3 Install the ECU bracket rivet.
4 Install the pressure sensor onto the seat cushion frame bracket, making sure the retaining ear is completely engaged.
5 Attach the pressure sensor hose.
6 Connect the main seat wire harness OCS electrical connector to the service part OCS electrical connector.
7 Tie-strap all loose wire harnesses and electrical connectors safely aside.
All seats
10. Align the seat cushion trim cover to the seat cushion pad and fasten the hook-and-loop strips.
11. Position the seat cushion trim cover and attach the J-clips.
Seats with power lumbar
12. Connect the power lumbar switch electrical connector.
13. Attach the power lumbar switch and bezel to the seat.
Seats with manual recline
14. Install the seat backrest recliner handle.
Heated seats
15. Connect the cushion heated seat element electrical connector.
All seats
16. Install the seat track.
17. Install the front seat backrest.
18. Install the front seat.
- Make sure the safety belts and buckles are accessible to the occupants after installation.
19. Repower the SRS. Do not prove out the system at this time.
20. WARNING: Install a new occupant classification sensor (OCS) system service kit as a complete assembly. Never install only part of the kit components. Failure to follow this instruction may result in incorrect operation of the OCS system and increases the risk of serious personal injury or death in a crash.
CAUTION:
- It is necessary to carry out the occupant classification sensor (OCS) system reset when a front passenger seat cushion is disassembled, a new trim cover installed or an OCS service kit is installed. A scan tool is used to trigger the active command to carry out the OCS system reset.
- Make sure the seat is completely assembled to prevent system failure before carrying out the occupant classification sensor (OCS) system reset active command.
- The following precautions must be taken before carrying out the occupant classification sensor (OCS) system reset.
- 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 OCS system reset 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 carrying out the OCS system reset and nothing is placed on the seat during the process.
- Make sure a minimum 8 second time period has passed after cycling the ignition switch ON before carrying out the OCS system reset process.
NOTE:
- For best results, the OCS system should be at or near room temperature, 10°C to 29°C (50°F to 85°F).
- If the first attempt to carry out the OCS system reset is unsuccessful, a second attempt must be made.
Carry out the OCS system reset active command using the scan tool.
- With the front passenger seat empty, use a scan tool to trigger the active command.
21. NOTE: The ignition switch must be cycled after the OCS system reset.
Cycle the ignition switch from ON to OFF.
22. Prove out the SRS as follows:
Turn the ignition key from ON to OFF. Wait 10 seconds, then turn the key back to ON and visually monitor the air bag indicator with the air bag modules installed. The air bag indicator will light continuously for approximately 6 seconds and then turn off. If an air bag SRS fault is present, the air bag indicator will:
- fail to light.
- remain lit continuously.
- flash.
The flashing might not occur until approximately 30 seconds after the ignition switch has been turned from the OFF to the ON position. This is the time required for the RCM to complete the testing of the SRS. If the air bag indicator is inoperative and a SRS fault exists, a chime will sound in a pattern of 5 sets of 5 beeps. If this occurs, the air bag indicator and any SRS fault discovered must be diagnosed and repaired.
Clear all continuous DTCs from the RCM using a scan tool.
23. NOTE: When installing a new OCS, a prepaid return postcard is provided with the new OCS. The serial number for the new part and the vehicle identification number (VIN) must be recorded and sent to Ford Motor Company.
Fill out the necessary information on the OCS traceability card and return it along with the complete inoperative occupant classification sensor to Ford Motor Company.
- When returning the inoperative OCS include: seat cushion foam pad, bladder, electronic control unit, pressure sensor (transducer), hose, electrical connectors and wire harness (service part OCS only).
