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Problem Symptoms Table

PROBLEM SYMPTOMS TABLE - FRONT POWER SEAT CONTROL SYSTEM

Symptom Suspected Area
All functions do not operate. (Driver side)
  • 3. ECU power source circuit (Driver seat ECU)

If the suspected area above is functioning normally, replace the driver seat ECU(1).
Slide operation does not operate. (Driver side)
  1. Motor circuit
  2. Position sensor circuit

If the 2 suspected areas above is functioning normally, replace the driver seat ECU(1).
Front vertical operation does not operate. (Driver side)
  1. Motor circuit
  2. Position sensor circuit

If the 2 suspected areas above is functioning normally, replace the driver seat ECU(1).
Lifter operation does not operate. (Driver side)
  1. Motor circuit
  2. Position sensor circuit

If the 2 suspected areas above is functioning normally, replace the driver seat ECU(1).
Reclining operation does not operate. (Driver side)
  1. Motor circuit
  2. Position sensor circuit

If the 2 suspected areas above is functioning normally, replace the driver seat ECU(1).
Headrest operation does not operate. (Driver side)
  1. Motor circuit
  2. Position sensor circuit

If the 2 suspected areas above is functioning normally, replace the driver seat ECU(1).
Seat cushion operation does not operate. (Driver side)
  1. Seat cushion switch circuit
  2. Motor circuit
  3. Position sensor circuit

If the 3 suspected areas above is functioning normally, replace the driver seat ECU(1).
Seat position memory return function does not operate. (Driver side)
  1. Driving position memory switch circuit (w/Memory)
  2. Position sensor circuit

If the 2 suspected areas above is functioning normally, replace the driver seat ECU(1).
Lumbar support operation does not operate. (Driver side)
  1. Lumbar support switch circuit
  2. Motor circuit
  3. Position sensor circuit

If the 3 suspected areas above is functioning normally, replace the driver seat ECU(1).
Driving position memory system does not operate. (Driver side)
  1. Driving position memory switch circuit (w/Memory)
  2. ECU power source circuit (Driver door ECU)

If the 2 suspected areas above is functioning normally, replace the driver seat ECU(1) and driver door ECU.
All functions do not operate. (Passenger side)
  1. PP/SEAT fuse
  2. Wire harness
Slide operation does not operate. (Passenger side)
  1. Power seat switch (passenger side)
  2. Power seat switch sub (passenger side)
  3. Power seat motor
  4. Wire harness
Front vertical operation does not operate. (Passenger side)
  1. Power seat switch (passenger side)
  2. Power seat motor
  3. Wire harness
Lifter operation does not operate. (Passenger side)
  1. Power seat switch (passenger side)
  2. Power seat motor
  3. Wire harness
Reclining operation does not operate. (Passenger side)
  1. Power seat switch (passenger side)
  2. Power seat switch sub (passenger side)
  3. Power seat motor
  4. Wire harness
Headrest operation does not operate. (Passenger side)
  1. Power seat switch (passenger side)
  2. Power seat motor
  3. Wire harness
Lumbar support operation does not operate. (Passenger side)
  1. Power seat switch (passenger side)
  2. Power seat motor
  3. Wire harness
(1) After replacing the driver seat ECU, initialize the front power seat (see initialization).