Test No. 3, Control Switch Circuit
- Turn ignition off. Check cruise control switch. See CRUISE CONTROL SWITCH under COMPONENT TESTING. Replace cruise control switch as necessary and recheck system operation. If switch is okay, go to next step.
- Locate slip ring connectors under steering wheel. Disconnect slip ring connectors. See Fig 1. Check for continuity between ground and slip ring 6-pin connector terminal No. 5 (White/Black wire) on models with air bag or terminal No. 4 (White/Black wire) on models without air bag. On all models, if continuity exists, go to next step. If continuity does not exist, repair faulty ground, or locate and repair open in wiring harness between slip ring 6-pin connector and ground.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Check slip ring. See SLIP RING under COMPONENT TESTING . Replace slip ring as necessary and recheck system operation. If slip ring is okay, reconnect slip ring connectors and go to next step.
- Disconnect CC ECU connector. See Figure. Check for continuity between ground and CC ECU connector terminal No. 13 (White/Black wire). If continuity exists, go to next step. If continuity does not exist, repair faulty ground, or locate and repair open in wiring harness between ground and CC ECU connector.
- With cruise control switch off, check for continuity between CC ECU connector terminals No. 13 (White/Black wire) and 18 (Green/Yellow wire). If continuity exists, go to next step. If continuity does not exist, locate/repair short between CC ECU connector terminal 18 and slip ring 6-pin connector terminal No. 6.
- With cruise control RES/ACC on, measure resistance between CC ECU connector terminals No. 13 (White/Black wire) and No. 18 (Green/Yellow wire). If resistance is about 68 ohms, replace CC ECU and recheck system operation. If resistance is not about 68 ohms, locate and repair open in wiring harness between CC ECU connector terminal No. 18 and slip ring 6-pin connector terminal No. 6.