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Test No. 3: Control Switch Circuit

  1. Disconnect Black 20-pin combination switch connector C15. Combination switch connector C15 is located behind left side of instrument panel, below steering column. Check for continuity between ground and Black 20-pin combination switch connector C15 terminal No. 20 (Brown wire). If continuity exists, go to next step. If continuity does not exist, repair faulty ground, or locate and repair open Brown wire between ground and Black 20-pin combination switch connector C15.
  2. Check cruise control switch. See CRUISE CONTROL SWITCH TEST  under COMPONENT TESTS. Replace switch as necessary and recheck system operation. If switch is okay, reconnect Black 20-pin combination switch connector C15 and go to next step.
  3. Disconnect CC ECU connector C17. See Figure. With cruise control switch in OFF position, check for continuity between ground and CC ECU connector C17 terminal No. 19 (Yellow/Red wire). If continuity does not exist, go to next step. If continuity exists, locate and repair short in Yellow/Red wire between CC ECU connector C17 and cruise control switch.
  4. With cruise control switch in ON position, check for continuity between ground and CC ECU connector C17 terminal No. 19 (Yellow/Red wire). If continuity exists, go to next step. If continuity does not exist, locate and repair open in Yellow/Red wire between CC ECU connector C17 and cruise control switch.
  5. With cruise control switch in OFF position, check for continuity between ground and CC ECU connector C17 terminal No. 18 (Black/Green wire). If continuity does not exist, go to next step. If continuity exists, locate and repair short in Black/Green wire between CC ECU connector C17 and cruise control switch.
  6. With cruise control switch in specified position, measure resistance between ground and CC ECU connector C17 terminal No. 18 (Black/Green wire). See CRUISE CONTROL SWITCH RESISTANCE table. If resistance is as specified, check CC ECU. See PIN VOLTAGE TESTS . If found to be defective, replace CC ECU and recheck system operation. If resistance is not as specified, locate and repair open in Black/Green wire between CC ECU connector C17 and cruise control switch.
CRUISE CONTROL SWITCH RESISTANCE

Switch Position (1) Ohms
RES/ACC 68
SET/COAST 198
CANCEL 418
(1) Specification is approximate.
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