Disconnect the negative (-) battery terminal.

Remove the seat heater switch from the floor console (A) with scraper.

Check that continuity exists between the terminals.

Terminal No : 1. Ground, 2. High signal switch

3. Low signal switch, 5. Illumination (-),

6. Illumination (+)

Disconnect the negative (-) battery terminal.

Remove the rear door trim. (Refer to Body group - "Rear door")

Turn 2nd seat heater switch ON and check that continuity exists between the terminals.