Diagnosis & Repair
WARNING: This page is about a different car, the 2002 Lexus GS 430. However, it is still accessible from the selected car via links, so may be relevant.
- Check ETCS fuse (15-amp) located in engine compartment fuse/relay box on passenger side firewall. If ETCS fuse is okay, go to next step. If ETCS fuse is blown, check for short circuit in wiring harness between ETCS fuse and ECM. See WIRING DIAGRAMS article. Repair wiring as necessary.
- Backprobing, measure voltage between ground and terminal No. 7 (Violet/Yellow wire) at ECM E6 connector. See Figure. If voltage is 9-14 volts, replace ECM and retest. If voltage is not 9-14 volts, check circuits in wiring harness between battery, ETCS fuse and ECM. See WIRING DIAGRAMS article. Repair wiring as necessary.