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Power & Ground Circuit Tests

WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition off. Remove seat. See POWER SEAT  under REMOVAL & INSTALLATION. Disconnect 4-pin electrical harness connector from lumbar support switch. Remove lumbar support switch.
  2. Check continuity of ground circuit by connecting positive lead of DVOM to lumbar support switch 4-pin electrical harness connector terminal No. 2 (White/Black wire) and negative lead of DVOM to good body ground point. If resistance is greater than one ohm, repair ground circuit between lumbar support switch and ground point. If ground circuit is okay, go to next step. Ground point for driver seat with driving position memory is located in engine compartment on left front inner quarter panel. Ground point for driver seat without driving position memory is located at left front corner of luggage compartment (trunk). See MEMORY SYSTEMS and POWER SEATS in SYSTEM WIRING DIAGRAMS article.
  3. Check power feed circuit by connecting positive lead of DVOM to lumbar support switch 4-pin electrical harness connector terminal No. 1 (Blue/Orange wire) and negative lead of DVOM to good body ground point. If 10-14 volts is not present, repair power feed circuit between lumbar support switch and battery. See MEMORY SYSTEMS and POWER SEATS in SYSTEM WIRING DIAGRAMS article.