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Procedure L, Electronically Controlled Transmission Solenoid Circuit

  1. Engine/Transmission ECU:  Start engine and allow it to idle. Check for 5-volt reference voltage between engine/transmission ECU terminal No. 21 (22-pin connector) and ground. See Figure. If voltage is correct, go to next step. If voltage is incorrect, repair short or open circuit in wire harness between cruise control ECU terminal No. 7 and engine/transmission ECU terminal No. 21 (22-pin connector).
  2. Cruise Control ECU:  Stop engine and disconnect engine/transmission ECU. Check continuity between wiring harness side of cruise control ECU terminal No. 9 and wiring harness side of engine/transmission ECU terminal No. 18 (26-pin connector). See Figure. If continuity exists, go to next step. If no continuity exists, repair open circuit in wire harness between cruise control ECU terminal No. 9 and engine/transmission ECU terminal No. 18 (26-pin connector).
  3. Check resistance between wiring harness side of engine/transmission ECU terminal No. 18 (26-pin connector) and ground. If resistance is 11-15 ohms, replace faulty cruise control ECU and recheck cruise control system. If resistance is incorrect, repair short or open circuit in wire harness between cruise control ECU terminal No. 9 and engine/transmission ECU terminal No. 18 (26-pin connector), or electronically controlled transmission solenoid No. 2.
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