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Home >> Lexus >> 2012 >> IS F >> Repair and Diagnosis >> Body & Frame >> Seats >> Front Power Seat Control System (Diagnostics & Circuit Tests) >> Front Power Seat Control System >> Problem Symptoms Table >> Problem Symptoms Table
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Problem Symptoms Table

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FRONT POWER SEAT CONTROL SYSTEM (DRIVER SEAT)

Symptom Suspected Area Refer To
Power Seat does not Operate (Manual or Memorized Position). Driver side ECU power source circuit Refer to Driver Side ECU Power Source Circuit 
Front power seat switch LH (Position control ECU) -
One of the Power Seat Functions does not Operate (Manual or Memorized Position). Driver side power seat motor circuit Refer to Driver Side Power Seat Motor Circuit 
Front power seat switch LH (Position control ECU) -
One or All Manual Seat Functions do not Operate (Memorized Positions OK). Front power seat switch LH (Position control ECU) Refer to REMOVAL
Memory Function does not Operate. Driver side seat memory switch circuit Refer to Driver Side Seat Memory Switch Circuit 
Multiplex communication system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Front power seat switch LH (Position control ECU) -
No Memory Functions Operate or All Memory Functions Operate Briefly and then Stop (Manual Functions OK). Driver side ECU power source circuit Refer to Driver Side ECU Power Source Circuit 
Front power seat switch LH (Position control ECU) -
One Memory Function does not Operate or Operates Briefly and then Stops (manual functions OK). Power seat motor Refer to INSPECTION
Front power seat switch LH (Position control ECU) -
Wireless Transmitter Memory Function does not Operate. Perform the operation check. Refer to OPERATION CHECK 
Check the wireless door lock operation. Refer to OPERATION CHECK
Driver side seat memory switch circuit Refer to Driver Side Seat Memory Switch Circuit 
Multiplex communication system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Front power seat switch LH (Position control ECU) -
Wireless-linked Return Function does not Operate. Perform the operation check. Refer to OPERATION CHECK 
Check the wireless door lock operation. Refer to OPERATION CHECK
Driver side seat memory switch circuit Refer to Driver Side Seat Memory Switch Circuit 
Drive side power seat motor circuit Refer to Driver Side Power Seat Motor Circuit 
Multiplex communication system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Front power seat switch LH (Position control ECU) -
FRONT POWER SEAT CONTROL SYSTEM (FRONT PASSENGER SEAT)

Symptom Suspected Area Refer To
Power Seat does not Operate (Manual or Memorized Position). Front passenger side ECU power source circuit Refer to Front Passenger Side ECU Power Source Circuit 
Front power seat switch RH (Position control ECU) -
One of the Power Seat Functions does not Operate (Manual or Memorized Position). Front passenger side power seat motor circuit Refer to Front Passenger Side Power Seat Motor Circuit 
Front power seat switch RH (Position control ECU) -
One or All Manual Seat Functions do not Operate (Memorized Positions OK). Front power seat switch RH (Position control ECU) Refer to REMOVAL
Memory Function does not Operate. Front passenger side seat memory switch circuit Refer to Front Passenger Side Seat Memory Switch Circuit 
Multiplex communication system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Front power seat switch RH (Position control ECU) -
No Memory Functions Operate or All Memory Functions Operate Briefly and then Stop (Manual Functions OK). Front passenger side ECU power source circuit Refer to Front Passenger Side ECU Power Source Circuit 
Front power seat switch RH (Position control ECU) -
One Memory Function does not Operate Briefly and then Stops (Manual Functions OK). Power seat motor Refer to INSPECTION
Front power seat switch RH (Position control ECU) -