Circuit Description

WARNING: This page is about a different car, the 1995 Lexus LS 400. However, it is still accessible from the selected car via links, so may be relevant.

The ECT sensor is a thermistor sensor that monitors coolant temperature. Code is set when ECM detects a open or short circuit. Possible causes are:

ECT sensor open or short circuit.
ECT sensor malfunction.
ECM malfunction.

NOTE: If Codes P0110, P0115 and P0120 are output together, inspect ECM terminal E2 (ground) circuit. Repair as needed. See appropriate wiring diagram in WIRING DIAGRAMS article.