Malfunction Of Lumbar Operation

1. Turn the ignition switch to OFF.
2. Disconnect the power seat switch connector.
3. Measure the resistance between connector terminals when moving the switch to lumbar forward and lumbar backward. Ref. to SEATS>POWER SEAT>INSPECTION>POWER SEAT SWITCH .

Is the inspection result normal?

Yes:  Go to  2.

No:  Replace the power seat switch assembly. Ref. to SEATS>POWER SEAT .

1. Disconnect the lumbar motor connector.
2. Measure the resistance between power seat switch connector and lumbar motor connector.

   Connector & terminal 

   (St52) No. 18 - (St70) No. 2: 

   (St52) No. 9 - (St68) No. 1: 

Is the resistance less than 10 Ω?

Yes:  Go to  3.

No:  Check power seat harness.

1. Connect the power seat switch connector and lumbar motor connector.
2. Apply battery voltage to the lumbar motor and check the motor rotation.

   Connector & terminal 

   (St70) No. 2 (+) - (St70) No. 1 (-): 

   (St70) No. 1 (+) - (St70) No. 2 (-): 

Does the motor rotate normally?

Yes:  Check for temporary poor contact or mechanical trouble (flat mat & hook spring assembly) in lumbar support mechanism.

No:  Lumbar motor problem. Replace the flat mat & hook spring assembly.