Speed Sensor Circuit Test
- Turn ignition on and check speed sensor ground by disconnecting connector from combination meter. Check for continuity between terminal 23 (Celica and Supra), 30 (Cressida), 19 (Corolla RWD), 20 (Corolla FWD), 16 (Pickup & 4Runner) or 3 (Van) and ground. If continuity exists, check for short. If no continuity, check computer.
- Disconnect computer. Disconnect connector from combination meter. On harness side, check for continuity between terminal 23 (Celica and Supra), 18 (Corolla RWD), 20 (Corolla FWD), 16 (Pickup & 4Runner) or 2 (Van) and terminal 6 (Celica, Cressida, Supra, Corolla) or 7 (all others) of computer. If no continuity, check for open in circuit.
- If continuity exists, inspect speed sensor operation by checking if circuit between terminal 6 (Celica, Cressida, Supra and Corolla) or 7 (all others) and ground repeats from on to off about every 16" that vehicle moves. For Cressida, check for continuity between terminals 8 and 20 four times per each revolution of the shaft. If yes, replace computer. If not, speed sensor is faulty.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002