Test No. 12: DTC Not Output, Or DTC Output When It Should Not Be
WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
- Locate Gray round 17-pin Data Link Connector No. 2 (DLC2) under left side of instrument panel, to right of driver side junction block. Turn ignition on. Measure voltage between 17-pin DLC2 terminals Tc and E1. See Figure. If battery voltage is not present, go to next step. If battery voltage is present, no problem is indicated at this time. Fault may be intermittent, go to step 3.
- Turn ignition off. Disconnect cruise control ECU 16-pin electrical harness connector. Using a DVOM, check for open and short circuit conditions in Light Green/Red wire between cruise control ECU 16-pin electrical harness connector terminal No. 5 and DLC2 terminal Tc. See Figure and Figure . Also check harness and connectors between cruise control ECU and DLC2. If wires, harnesses and connectors are okay, go to next step. If wires, harnesses and connectors are not okay, repair fault as required. See CRUISE CONTROL in SYSTEM WIRING DIAGRAMS article. After repairs, perform confirmation test. See CONFIRMATION TEST .
- Turn ignition off. Disconnect cruise control ECU 16-pin electrical harness connector. Using DVOM, check cruise control ECU ground circuit. See CRUISE CONTROL in SYSTEM WIRING DIAGRAMS article. If ground circuit is faulty, repair and retest system. If ground circuit is okay, substitute original cruise control ECU with a known-good unit and recheck system operation. If system operates properly, original cruise control ECU was defective. If system still does not operate properly, perform cruise control ECU pin voltage check. See PIN VOLTAGE TESTS . Check wiring harness and electrical connectors for an intermittent problem. Repair wiring harnesses or connectors as necessary. See CRUISE CONTROL in SYSTEM WIRING DIAGRAMS article. If voltage values, harnesses and connectors are okay, replace cruise control ECU. See CRUISE CONTROL ELECTRONIC CONTROL UNIT under REMOVAL & INSTALLATION. After repairs, perform confirmation test. See CONFIRMATION TEST .