Inspection Procedure

HINT:

If there is not the hand-held tester, begin with STEP  2.

1. Check position sensor signal. 

   PREPARATION: 

   1. Connect the hand-held tester to the DLC3.
   2. Turn ignition switch ON and hand-held tester main switch ON.
   3. Select the DATALIST mode on the hand-held tester.

   CHECK: 

   1. When operating each adjustment function of seat by turning the power seat control switch of the vehicle, check that "Position sensor" value changes on the screen of hand-held tester.
   2. When operating each adjustment function of seat by turning the power seat control switch of the vehicle, check that "Motor status" changes from "OFF" to "ON" on the screen of the hand-held tester.

   HINT:

   When the seat is moved to the limit positions, "Lock" is displayed in the column of "Motor status" on the screen of the hand-held tester. At that time, if the power seat control switch is released, it turns OFF.

   OK: 

   Both "Position sensor" value and "Motor status" are changing. 

   1. OK: Check and replace power seat position ECU (See  HOW TO PROCEED WITH TROUBLESHOOTING  ). 
   2. NG: Go to next step. 
2. Check position sensor. 

   PREPARATION: 

   Disconnect the connector of the sensor and the connector of the motor leading to the sensor.

   CHECK: 

   1. Connect positive (+) lead to terminal 3 of sensor and negative (-) lead to terminal 2.
   2. Measure voltage between terminal 1 of sensor and body ground when battery positive voltage is applied between terminals 1 and 2 of motor connector.
   Fig 1: Checking Position Sensor

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   HINT:

   When the battery positive voltage is applied to the motor connector terminals, (+) and (-) are interchangeable.

   OK: 

   POSITION SENSOR VOLTAGE
   
   

   Condition	Voltage
   Motor stopped (Check several times with the motor in a different position each time)	0V or battery positive voltage according to stop position
   Motor running	Half of battery positive voltage

   1. NG: Replace power seat motor. 
   2. OK: Go to next step. 
3. Check harness and connectors between power seat position ECU and position sensors (See  HOW TO PROCEED WITH TROUBLESHOOTING  ). 
   1. NG: Repair or replace harness or connectors. 
   2. OK: Check and replace power seat position ECU (See  HOW TO PROCEED WITH TROUBLESHOOTING  ).