Power Source Circuit
- Check ECU-IG fuse and replace if faulty. If fuse is okay, go to next step. If fuse failure is continuous, disconnect cruise control Electronic Control Unit (ECU) wire harness connector. Install NEW fuse. Turn ignition on and check fuse. If fuse fails, check for short circuit in wire harness. If fuse is okay, replace ECU.
- Disconnect ECU wire harness connector. Check for continuity between ECU ground terminal and body ground. See ECU CONNECTOR GROUND & POWER TERMINAL IDENTIFICATION table. See Fig 1- Fig 5 . for ECU connector terminal identification. If continuity is not present, repair open in circuit. If continuity is present, go to next step.
- Turn ignition on. Measure voltage between power terminal and ground. See ECU CONNECTOR GROUND & POWER TERMINAL IDENTIFICATION table. If battery voltage is not present, repair open in circuit. If battery voltage is present, replace ECU.
ECU CONNECTOR GROUND & POWER TERMINAL IDENTIFICATION
| Application | Ground Terminal | Power Terminal | |
|---|---|---|---|
| Camry, Land Cruiser, MR2, Paseo & Previa | 13 | 14 | |
| Corolla | GND | IGB | |
| Celica | |||
| Motor Actuator | A9 | A1 | |
| Vacuum Actuator | 15 | 12 | |
| Cressida | A7 | B1 | |
| Supra, Pickup, & 4Runner | 15 | 12 | |