Diagnosis & Repair
WARNING: This page is about a different car, the 2002 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.
- Test drive vehicle and check operation of speedometer. If speedometer operates properly, go to next step. If speedometer does not operate properly, repair speedometer as necessary. See appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. Speedometer may not operate, as input signal from vehicle speed sensor may not be input to instrument cluster. Vehicle speed sensor is located near rear of transmission or transfer case and contains a Black 3-pin electrical connector with Yellow, Yellow/Red and Red/Blue wires. For testing of vehicle speed sensor, see VEHICLE SPEED SENSOR under ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING - V6 & V8 article.
- Remove glove box and heater duct (if necessary) for access to ECM with electrical connectors still installed on ECM. See Figure. Raise and support vehicle with one rear wheel off the ground. Turn ignition on. Place transmission in Neutral. Using voltmeter, check voltage between body ground and terminal No. 5 (Green/Orange wire) at ECM electrical connector E5 while rotating rear wheel. See Figure. This is the SPD terminal on ECM. Voltage should pulse between zero volts and 4-6 volts. If voltage is within specification, replace ECM. If voltage is not within specification, repair open or short in Green/Orange wire and electrical connectors between ECM and instrument cluster. See WIRING DIAGRAMS article.