Toyota Sienna Service Manual: Problem symptoms table

Toyota Sienna Service Manual / Seat / Front power seat control system / Problem symptoms table

HINT:

Inspect the fuse and relay before confirming the suspected areas in the table below.
Inspect each suspected area in numerical order for the corresponding symptom.

If the malfunction still exists after checking and confirming that all circuits and components are normal, replace the ECU.

FRONT POWER SEAT CONTROL SYSTEM ( w/o MEMORY)

Symptom	Suspected area
Power seat does not operate (slide, front vertical, lifter, reclining).	P/SEAT fuse Power seat switch Wire harness or connector
Slide operation function only does not operate.	Power seat switch Front seat frame with adjuster (LH side slide motor) Front seat frame with adjuster (RH side slide motor) Wire harness or connector
Front vertical operation function only does not operate.	Power seat switch Front seat frame with adjuster (LH side front vertical motor) Wire harness or connector
Lifter operation function only does not operate.	Power seat switch Front seat frame with adjuster (LH side lifter motor) Wire harness or connector
Reclining operation function only does not operate.	Power seat switch Front seat frame with adjuster (LH side reclining motor) Front seat frame with adjuster (RH side reclining motor) Wire harness or connector
Lumbar support operation function only does not operate (Driver side only).	Front power seat lumbar switch Lumbar support adjuster assembly Wire harness or connector

FRONT POWER SEAT CONTROL SYSTEM ( w/ MEMORY)

Symptom	Suspected area
Power seat does not operate (manual or memorized position).	ECU power source circuit Position control ECU and switch assembly (power seat control switch and ECU)
One of the power seat functions does not operate (manual or memorized position).	Power seat motor circuit Position control ECU and switch assembly (power seat control switch and ECU)
One or all manual seat functions do not operate (memorized positions OK).	Position control ECU and switch assembly (power seat control switch
Memory function does not operate.	Memory switch circuit Multiplex communication system Position control ECU and switch assembly (power seat control switch
No memory functions operate or all memory functions operate briefly	ECU power source circuit Position control ECU and switch assembly (power seat control switch
One memory function does not operate or operates briefly and then stops	Front seat frame with adjuster (power seat motor) Position control ECU and switch assembly (power seat control switch

How to proceed with troubleshooting

HINT: Use this procedure to troubleshoot the front power seat control system. The intelligent tester should be used in steps 3 and 5. 1 VEHICLE BROUGHT TO WORKSHOP 2 CUSTOMER P ...

Terminals of ECU

1. POSITION CONTROL ECU AND SWITCH ASSEMBLY (POWER SEAT CONTROL SWITCH AND ECU) Disconnect the P58 and P59 connectors. Check the voltage of each terminal of the wire harness sid ...

Other materials:

Inspection
1. INSPECT MASS AIR FLOW METER Visually check for any foreign matter on the platinum hot wire (heater) of the mass air flow meter. OK: There is no foreign matter. If the result is not as specified, replace the mass air flow meter. Measure the resistance according to the ...

Eject Error/ Elevator Error/ Clamp Error
DTC 63-45 Eject Error DTC 63-51 Elevator Error DTC 63-52 Clamp Error DESCRIPTION DTC No. DTC Detection Condition Trouble Area 63-45 Magazine cannot be ejected. Radio and navigation assembly 63-51 Mechanical error occurs during elevator ...

Canceling and resuming the speed control
Pulling the lever toward you cancels the cruise control. The speed setting is also canceled when the brakes are applied. Pushing the lever up resumes the cruise control and returns vehicle speed to the set speed. Resuming is available when the vehicle speed is more than approxi ...