Starter Relay Circuit Test: LS400
- Remove 3 screws and driver's side trim panel. Remove left instrument panel and key cylinder pad sub-assemblies. Remove bracket finish panel. Remove left register heater duct. Remove fuse/relay/junction block set bolts and clamp.
- Separate the tilt and telescopic ECU from fuse/relay/junction block. Remove wiring harness clamp. Pull fuse/relay/junction block down. Locate theft deterrent ECU above fuse/relay/junction block (under left side of instrument cluster).
- Disconnect theft deterrent ECU connectors. Place transmission in Neutral. Measure voltage between terminal ST of theft deterrent ECU wiring harness connector and body ground while turning ignition switch to ST (start) position. See Fig 1.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- If voltage is not 10-14 volts, check and repair harness/connections between starter relay and theft deterrent ECU. If voltage is 10-14 volts and starter relay circuit is still inoperative, test and replace theft deterrent ECU.