DESCRIPTION & OPERATION
| WARNING | Vehicles are equipped with air bag supplemental restraint system. Before attempting any repairs involving steering column, instrument panel or related components, see SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR BAG SYSTEM in AIR BAG RESTRAINT SYSTEMS article. |
| CAUTION | When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION before disconnecting battery. |
Power Seat Operation
Current is always applied to terminal SYSB and terminal +B of the memory seat ECU so that the memory seat ECU is always ready to operate.
When the power seat control switch is pushed to the FRONT SLIDE position side, a signal is input into terminal SLDF of the memory seat ECU, the ECU operates and the current to terminal +B of the memory seat ECU flows from terminal SLD+ of the memory seat ECU to terminal No. 2 of the power seat motor (driver's seat slide control) to terminal No. 1 to terminal SLD- of the memory seat ECU to terminal GND to ground, rotating the power seat motor so that the seat slides forward while the power seat control switch is being pressed.
To slide the driver's seat to the rear, pushing the power seat control switch to the REAR SIDE position side, inputs a signal to terminal SLDR of the memory seat ECU. This causes the current flowing from the ECU to the motor to flow from terminal SLD- of the memory seat ECU to terminal No. 1 of the power seat motor (driver's seat slide control) to terminal No. 2 to terminal SLD+ of the memory seat ECU, flowing the reverse to front slide operation and causing the motor to rotate in reverse, so that the driver's seat moves to the rear.
The movement to other positions occurs similarly, so only the flow of current to each motor is shown
- Front Vertical Up Operation - Terminal +B of the memory seat ECU to terminal FRV+ to terminal No. 1 of the power seat motor (driver's seat front vertical control) to terminal No. 2 to terminal FRV- of the ECU to terminal GND to ground.
- Front Vertical Down Operation - Terminal +B of the memory seat ECU to terminal FRV- to terminal No. 2 of the power seat motor (driver's seat front vertical control) to terminal No. 1 to terminal FRV+ of the ECU to terminal GRN to ground.
- Lifter Control Up Operation - Terminal +B of the memory seat ECU to terminal RRV+ to terminal No. 1 of the power seat motor (driver's seat lifter control) to terminal No. 2 to terminal RRV- of the ECU to terminal GND to ground.
- Lifter Control Down Operation - Terminal +B of the memory seat ECU to terminal RRV- to terminal No. 2 of the power seat motor (driver's seat lifter control) to terminal No. 1 to terminal RRV+ of the ECU to terminal GND to ground.
- Reclining Control Front Operation - Terminal +B of the memory seat ECU to terminal RCL+ to terminal No. 2 of the power seat motor (driver's seat reclining control) to terminal No. 1 to terminal RCL- of the ECU to terminal GND to ground.
- Reclining Control Rear Operation - Terminal +B of the memory seat ECU to terminal RCL- to terminal No. 1 of the power seat motor (driver's seat reclining control) to terminal No. 2 to terminal RCL+ of the ECU to terminal GND to ground.
SYSTEM OPERATION CHECK
- Trouble shooting of a power seat system complaint begins with verification of the customer problem. Perform the Customer Problem Analysis Check (Power Seat Control System). (Scheme 1)
- Determine and confirm symptom. See «POWER SEAT PROBLEM SYMPTOMS»(ref-152272-S09038562162003012400000). Without applicable symptoms, go to step 3. With applicable symptoms, go to step 4. POWER SEAT PROBLEM SYMPTOMS Symptom Suspected Area Both Manual & Return Functions Do Not Operate (All Functions) Power Source Circuit (1), Power Seat Control Switch Circuit (2), Seat Position Control ECU (3) Or Wiring Harness Both Manual & Return Functions Do Not Operate (One Function Only) Motor Circuit (4), Seat Position Control ECU (3), Seat Position Motor (5) Or Wiring Harness One Or All Functions Do Not Operate For Manual Operation Only Power Seat Control Switch Circuit (2), Seat Position Control ECU (3) Or Wiring Harness Memory Function Does Not Operate Power Seat Memory Switch Circuit (6), Ignition Switch Circuit, Park/Neutral Position Switch Circuit (7), Seat Position Control ECU Or Wiring Harness Only Return Function Does Not Operate Or Operates A Little, Then Stops (All Return Functions) Seat Position Control ECU (3) Only Return Function Does Not Operate Or Operates A Little, Then Stops (Only One Return Function) Seat Position Control ECU (3) Or Power Seat Motor (5) Power Seat Does Not Operate Front Power Seat Switch (5), PWR SEAT Fuse Or Wiring Harness Power Seat Does Not Slide Front Power Seat Switch (5), Front Slide Power Seat Motor Assembly (Slide) (5) Or Wiring Harness Front Vertical Of Power Seat Does Not Operate (Driver's Seat Only) Front Power Seat Switch (5), Front Up/Down Power Seat Motor Assembly (Front Vertical) (5) Or Wiring Harness Rear Lifter Of Power Seat Does Not Operate (Driver's Seat Only) Front Power Seat Switch (5), Power Seat Motor Assembly (Rear Vertical) (5) Or Wiring Harness Power Seat Does Not Recline Front Power Seat Switch (5), Power Seat Motor Assembly (Reclining) (5) Or Wiring Harness Lumbar Support Does Not Operate (Driver's Seat Only) Front Power Seat Switch (5), Power Seat Motor Assembly (Lumbar Support) (5) Or Wiring Harness Seat Heaters Do Not Operate SEAT HTR 20A Fuse, Front Seat Cushion Heater Assembly (8), Front Seat Back Heater Assembly (8), Heater Control Housing Sub-Assembly (A/C Amplifier) (9) Or Wiring Harness (1) See «POWER SOURCE CIRCUIT»(ref-152272-S06048312152003012400000) under COMPONENT TESTS. (2) See «POWER SEAT CONTROL SWITCH CIRCUIT»(ref-152272-S13543001902003012400000) under COMPONENT TESTS. (3) Inspect connector, check for open or short circuit, and check and replace ECU. (4) See «POWER SEAT MOTOR CIRCUIT»(ref-152272-S22708539582003012400000) under COMPONENT TESTS. (5) See «POWER SEAT INSPECTION»(ref-152272-S28132359602003012400000) under COMPONENT TESTS. (6) See «MEMORY SWITCH CIRCUIT»(ref-152272-S40924932392003012400000) under COMPONENT TESTS. (7) See «DIAGNOSIS - U150E»(ref-142323) under AUTOMATIC TRANSMISSION article in TRANSAXLE/TRANSMISSION. (8) See «SEAT HEATER INSPECTION»(ref-152272-S35050934832003012700000) under COMPONENT TESTS. (9) See «DTC 63: SEAT HEATER CIRCUIT (DRIVER SIDE)»(ref-152272-S06763507822003012700000) or «DTC 64: SEAT HEATER CIRCUIT (PASSENGER SIDE)»(ref-152272-S16514253972003012700000) under DIAGNOSTIC TESTS.
- Perform trouble shooting in the following method, depending on the malfunction symptom. Terminal Of ECU. See «TERMINALS OF ECU»(ref-152272-S10975822492003012400000) under COMPONENT TESTS. On-Vehicle Inspection. See «ON-VEHICLE INSPECTION (WITH MEMORY)»(ref-152272-S25255789932003012400000). Inspection. For memory seat switch inspection, see step 1 of MEMORY SWITCH CIRCUIT under COMPONENT TESTS. For power seat inspection, see «ON-VEHICLE INSPECTION (POWER SEAT OPERATION)»(ref-152272-S35417344092003012400000).
- Perform necessary adjustments, repairs or replacements.
- Perform a confirmation test. See «CONFIRMATION TEST»(ref-152272-S27931388892003012800000).
Scheme 1
ON-VEHICLE INSPECTION (POWER SEAT OPERATION)
Note. Inspection should be nod with the seat installed to the vehicle.
- Check power seat basic function. Check that each part can function properly (sliding, front vertical, lifter, reclining and lumbar support) by operating the power seat switch. (Scheme 2)
- Check power seat motor assembly (sliding). Inspect the PTC operation inside the power seat motor: Move the seat to any of the maximum front, rear, upper or lower position by operating the power seat switch and keep the seat there for approximately 60 seconds. Operating the power seat switch to move the seat to the position furthermore, measure the time (standard: approximately 4-90 seconds) until the electrical current will be shut down (motor operating sound will stop), inspection of the current shut-down. Turn the power seat switch off after the inspection of current shut-down and keep that condition for approximately 60 seconds. Operating the power seat switch to move the seat to the opposite position, check that the motor will operate.
- Check the left hand lumbar support adjuster assembly. Inspect the PTC operation inside the power seat motor: Move the lumbar support to either the front or rear maximum position by operating the lumbar support switch and keep it there for approximately 60 seconds. Operating the lumbar support switch to move the lumbar support to the position furthermore, measure the time (standard: approximately 4-90 seconds) until electrical current will be shut down (motor operating sound will stop), inspection of the current shut-down. Turn the lumbar support switch off after the inspection of current shut-down and keep that condition for approximately 60 seconds. Operating the lumbar support switch to move the lumbar support to the opposite position, check that the motor will operate.
