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Test No. 2: Set Function Not Occurring Or Cancel Function Occurring (No DTC Output)

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.
  1. Check ECU-IG No. 2 fuse (10-amp). ECU-IG No. 2 fuse is located in driver side junction block under left side of instrument panel. See Figure. If ECU-IG No. 2 fuse is okay, go to next step. If ECU-IG No. 2 fuse is defective, check for short between cruise control ECU 16-pin electrical harness connector terminal No. 9 (Yellow/Red wire) and ECU-IG No. 2 fuse. See CRUISE CONTROL in SYSTEM WIRING DIAGRAMS article. After repairs, perform confirmation test. See CONFIRMATION TEST .
  2. Turn ignition off. Remove cruise control ECU with connector attached. See Figure. Turn ignition on. Using a DVOM, measure voltage by backprobing between cruise control ECU 16-pin electrical harness connector terminals No. 9 (Yellow/Red wire) and No. 16 (White/Black wire). See Figure. If voltage is not 10-14 volts, go to next step. If voltage is 10-14 volts, no problem is indicated at this time. Fault may be intermittent, go to step  5.
  3. Turn ignition off. Remove cruise control ECU with connector attached. See Figure. Using a DVOM, measure resistance of ground circuit by backprobing between cruise control ECU 16-pin electrical harness connector terminal No. 16 (White/Black wire) and body ground point located under left side of instrument panel. See Figure. If resistance is less than 1 ohm, go to next step. If resistance is not less than 1 ohm, repair or replace wire, harness or connector as required. See CRUISE CONTROL in SYSTEM WIRING DIAGRAMS article. After repairs, perform confirmation test. See CONFIRMATION TEST .
  4. Check and repair all harnesses and connectors between cruise control ECU and battery. See CRUISE CONTROL in SYSTEM WIRING DIAGRAMS article. After repairs, perform confirmation test. See CONFIRMATION TEST .
  5. 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 .
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