Power Seats System: Overview Ford Windstar I

DESCRIPTION & OPERATION

The 6-way power seats provide horizontal, vertical and tilt adjustments. System consists of control switch, seat regulator motor, vertical and horizontal screw drives and gear mechanism, housing assembly and necessary wiring. Seat function switches are mounted on side of seat trim panel. Power seat circuits are protected by fuses and/or circuit breakers located in fuse panel and power distribution box. Some models are equipped lumbar support system.

Horizontal movement is controlled by a transmission, lead screw and motor attached to the movable section of the track. Vertical drive unit is located on left side of the movable track. Vertical operation energizes center and rear armatures and vertical drive units move seat up or down. In tilt operation, armatures move front or rear vertical drive screws to adjust seat. The motor unit is serviced as an assembly.

TEST F: IMPROPER HORIZONTALLY/VERTICALLY OPERATION

Note. Before beginning this test, ensure seat and seat track are free from all obstructions.

1. Test For Blinding Operated seat in all directions at seat control switch. If seat track is not binding, go to next step. If seat track is binding, replace seat track assembly.
2. Test Power Supply Disconnect seat control switch harness connector. Measure voltage at Dark Green wire of seat control switch harness connector. If battery voltage exists, go to next step. If battery voltage does not exist, repair open in Dark Green wire.
3. Test Seat Control Switch Test seat control switch. See «SEAT CONTROL SWITCH»(ref-29353-S11685513992001010800000) under COMPONENT TESTS. If seat control switch is okay, go to next step. If seat control switch is defective, replace seat control switch.
4. Test Ground Circuit Measure resistance between ground and Black wire at seat control switch harness connector. If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair open in Black wire.
5. Test For Open Measure resistance in wires between seat motor harness connector and seat control switch harness connector. See SEAT MOTOR CIRCUIT IDENTIFICATION table. If all resistance readings are 5 ohms or less, replace seat motor assembly. If any resistance reading is greater than 5 ohms, repair open in appropriate wire(s).

SEAT MOTOR CIRCUIT IDENTIFICATION

TEST G: IMPROPER HORIZONTAL OPERATION

Note. Before beginning this test, ensure seat and seat track are free from all obstructions.

1. Test For Open Disconnect seat motor harness connector. Disconnect seat control switch harness connector. Measure resistance in Yellow/White and Red/White wires between seat control switch and seat motor harness connectors. If both resistance readings are less than 5 ohms, go to next step. If either resistance reading is 5 ohms or greater, repair open in appropriate wire.
2. Test For Short Measure resistance between ground and Yellow/White and Red/White wires at seat control switch harness connector. If both resistance readings are 10 k/ohms or greater, go to next step. If either resistance reading is less than 10 k/ohms, repair short to ground in appropriate wire.
3. Test Motor Operation Using fused jumper wires, connect positive battery voltage to Red/White wire and ground Yellow/White wire at seat motor connector. Seat should move rearward. Reverse leads and seat should move forward. If seat operates as described, replace seat control switch. If seat does not operate as described, replace seat motor assembly.

TEST H: IMPROPER FRONT UP/DOWN OPERATION

Note. Before beginning this test, ensure seat and seat track are free from all obstructions.

1. Test For Open Disconnect seat motor harness connector. Disconnect seat control switch harness connector. Measure resistance in Yellow/Light Blue and Red/Light Blue wires between seat control switch and seat motor harness connectors. If both resistance readings are less than 5 ohms, go to next step. If either resistance reading is 5 ohms or greater, repair open in appropriate wire.
2. Test For Short Measure resistance between ground and Yellow/Light Blue and Red/Light Blue wires at seat control switch harness connector. If both resistance readings are 10 k/ohms or greater, go to next step. If either resistance reading is less than 10 k/ohms, repair short to ground in appropriate wire.
3. Test Motor Operation Using fused jumper wires, connect positive battery voltage to Red/Light Blue wire and ground Yellow/Light Blue wire at seat motor connector. Seat front should move down. Reverse leads and seat front should move up. If seat operates as described, replace seat control switch. If seat does not operate as described, replace seat motor assembly.

TEST J: IMPROPER REAR UP/DOWN OPERATION

Note. Before beginning this test, ensure seat and seat track are free from all obstructions.

1. Test For Open Disconnect seat motor harness connector. Disconnect seat switch harness connector. Measure resistance in Yellow/Light Green and Red/Light Green wires between seat control switch and seat motor harness connectors. If both resistance readings are less than 5 ohms, go to next step. If either resistance reading is 5 ohms or greater, repair open in appropriate wire.
2. Test For Short Measure resistance between ground and Yellow/Light Green and Red/Light Green wires at seat control switch harness connector. If both resistance readings are 10 k/ohms or greater, go to next step. If either resistance reading is less than 10 k/ohms, repair short to ground in appropriate wire.
3. Test Motor Operation Using fused jumper wires, connect positive battery voltage to Red/Light Green wire and ground Yellow/Light Green wire at seat motor connector. Seat rear should move down. Reverse leads and seat rear should move up. If seat operates as described, replace seat control switch. If seat does not operate as described, replace seat motor assembly.

TEST K: IMPROPER LUMBAR OPERATION

1. Test Voltage Out Of Switch Partially remove lumbar switch, leaving harness connector attached. Using a voltmeter, backprobe at Red wire of lumbar switch harness connector. Operated lumbar switch to inflate position. If battery voltage does not exist, go to next step. If battery voltage exists, go to step 3).
2. Switch Circuit Test Disconnect lumbar switch harness connector. Measure voltage at Dark Green at lumbar switch harness connector. If battery voltage does not exist, repair open in Dark Green wire. If battery voltage exists, replace lumbar switch.
3. Test For Pump/Motor Operation Operate lumbar switch to inflate position. If pump/motor does not run, go to next step. If pump/motor runs, go to step 7).
4. Test Voltage Supply To Pump/Motor Disconnect pump/motor harness connector. Measure voltage between Red and Black wires at pump/motor harness connector. Operate lumbar switch to inflate position. If battery voltage does not exist, go to next step. If battery voltage exists, replace pump/motor.
5. Test Power Supply To Pump/Motor Measure voltage at Red wire of pump/motor harness connector. Activate lumbar switch to inflate position. If battery voltage does not exist, go to next step. If battery voltage exists, repair open in Black wire.
6. Test For Open Measure resistance in Red wire between lumbar switch harness connector and pump/motor harness connector. If resistance is 5 ohms or greater, repair short in Red wire. If resistance is less than 5 ohms, replace lumbar switch.
7. Test Pump Adjusting System Activate lumbar switch to inflate position. Observe seatback pad. If seatback inflates, go to next step. If seatback does not inflate, go to step 10).
8. Test Airflow At Pump/Motor Remove support bladder hose from pump/motor. Activate lumbar switch to inflate position. If air is felt coming from pump/motor, go to next step. If no air is felt coming from pump/motor, replace pump/motor.
9. Test Airflow At Seat Switch Connect support bladder hose to pump/motor. Disconnect hose from lumbar switch. Activate lumbar switch to inflate position. If air is felt at open hose, go to next step. If no air is felt at open hose, replace hose.
10. Test System For Leaks Connect support bladder hose to pump/motor. Connect in-line pressure gauge to hose. Hold lumbar switch in inflate position until pressure is 5 psi (0.35 kg/cm 2 ). Wait 3 hours. Observe pressure. If pressure does not hold, go to next step. If pressure holds, system is okay.
11. Test Lumbar Support Bladder For Leaks Disconnect hose from lumbar support bladder. Using hand pump, inflate pad to 5 psi (0.35 kg/cm 2 ). Wait 3 hours. Observe pressure. If pressure does not hold, replace lumbar support bladder. If pressure holds, replace lumbar switch.