Power Seat System: Overview Ford Econoline E350

DESCRIPTION

Note. Aerostar uses only power lumbar support.

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.

OPERATION

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 OR NO POWER LUMBAR SUPPORT OPERATION

1. Switch Circuit Test - Disconnect lumbar switch. Check voltage at Black/White wire (Dark Green wire on Windstar) at lumbar switch harness connector. If battery voltage does not exist, go to next step. If battery voltage exists, go to step 5).
2. Test For Short To Ground - Remove power seat fuse, located in engine compartment fuse box. See «WIRING DIAGRAMS»(ref-29284-S23993362222001010800000) for fuse number and amperage. Check resistance in Black/White wire (Dark Green wire on Windstar) between lumbar switch harness connector and ground. If resistance is 10,000 ohms or more, go to next step. If resistance is less than 10,000 ohms, repair short in Black/White wire (Dark Green wire on Windstar).
3. Test Circuit Continuity - Check resistance of Black/White wire (Dark Green wire on Windstar) between lumbar switch harness connector and output side of power seat fuse terminal. If resistance is 5 ohms or less, install power seat fuse and go to next step. If resistance is more than 5 ohms, repair open in Black/White wire (Dark Green wire on Windstar).
4. Test Switch Operation - Connect lumbar switch. Using a voltmeter, backprobe Red wire at lumbar switch connector while activating lumbar switch to inflate position. If battery voltage exists, go to next step. If battery voltage does not exist, replace lumbar switch.
5. Test Pump/Motor - Activate lumbar switch to inflate position. If pump/motor does not run, go to next step. If pump/motor runs, go to step 9).
6. Test Pump/Motor Circuit - Disconnect connector from pump/motor. Check voltage between Black wire and Red wire at pump/motor harness connector. Activate lumbar switch to inflate position. If battery voltage does not exist, go to next step. If battery voltage exists, replace pump/motor.
7. Test Power Supply To Pump/Motor - Check 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.
8. Test For Short - Check resistance in Red wire between lumbar switch harness connector and ground. If resistance is 5 ohms or less, repair short in Red wire. If resistance is more than 5 ohms, replace lumbar switch.
9. Test Pump Adjusting System - Activate lumbar switch to inflate position. Observe seatback pad. If seatback does not inflate, go to next step. If seatback inflates, go to step 13).
10. Test Lumbar Support Bladder - Inspect support bladder. If no damage is visible, go to next step. If any damage is visible, replace support bladder.
11. 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.
12. 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.
13. Test System For Leaks - Reconnect support bladder hose to lumbar switch. 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.
14. 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.