Problem Symptoms Table

WARNING: This page is about a different car, the 2003 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.

Troubleshoot the circuits for the applicable problem symptom in the order given in the chart below. Proceed to the page for each circuit.

HINT:

If the instruction "Proceed to next circuit inspection shown on problem symptoms table" is given in the flow chart for each circuit, proceed to the circuit with the next highest number in the table to continue the check.
If the trouble still reappears even though there are no abnormalities in any of the other circuits, then check and replace the Power Seat Control ECU as the last step.

PROBLEM SYMPTOMS

Symptom	Suspected Area	Action
All the motors do not function when operating manually.	There is an object that blocks the inflared signal under the seat. Dirt on the signal reception part and emission part in the power seat control ECU or in the driver's seat control switch. ECU power source circuit +B power source circuit Power seat control switch circuit Power seat control ECU and Driver's seat control switch	PRE-CHECK ECU Power Source Circuit +B Power Source Circuit Power Seat Control Switch Circuit HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
All the motors do not function by manual operation (except for slide operation).	There is an object that blocks the inflared signal under the seat. Affected by the parts installed later (ornamental neon tube). Dirt on the signal reception part and emission part in the power seat control ECU or in the driver's seat control switch. Power seat control ECU and Driver's seat control switch	PRE-CHECK HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
One function do not operate by manual operation only.	Motor circuit Power seat control ECU	Motor Circuit HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
The movement is intermittent (all the motors) when operating manually.	ECU power source circuit +B power source circuit Power seat control switch circuit Power seat control ECU and Driver's seat control switch	ECU Power Source Circuit +B Power Source Circuit Power Seat Control Switch Circuit HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
The movement is intermittent (all the motors except for slide operation) when operating manually.	Affected by the parts installed later (remote controller using infrared light). Power seat control ECU and Driver's seat control switch	HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
The movement is intermittent (a pert of motors) when operating manually.	Position sensor power source circuit Position sensor circuit Motor circuit Power seat control ECU and Driver's seat control switch	Position Sensor Power Source Circuit Position Sensor Circuit Motor Circuit HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
The movement is different from the switch operation when operating manually.	There is an object that blocks the inflared signal under the seat. Dirt on the signal reception part and emission part in the power seat control ECU or in the driver's seat control switch. Power seat control ECU and Driver's seat control switch	HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
Motors move without any switch operation.	Driver's seat control switch Power seat control ECU	HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
The motors do not stop during manual operation.	There is an object that blocks the inflared signal under the seat. Switch nob Driver's seat control switch Power seat control ECU	HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
Return function does not operate or operates a little, then stops (ALL return functions).	ECU power source circuit +B power source circuit Ignition switch circuit Position sensor power source circuit Position sensor circuit Memory switch circuit Power seat control ECU Body ECU (Main)	ECU Power Source Circuit +B Power Source Circuit Ignition Switch Circuit Position Sensor Power Source Circuit Position Sensor Circuit MEMORY SWITCH CIRCUIT (W/MEMORY) HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE