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Home >> Lexus >> 2003 >> IS 300 Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 103 (Cruise Control System) >> Circuit Tests >> Cruise Control Switch Circuit >> Inspection Procedure
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Inspection Procedure

WARNING: This page is about a different car, the 2002 Lexus IS 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. Remove the ECM with the connector still connected. Turn the ignition switch ON. Measure the voltage between connector E4 terminal No. 31 (CCS) of the ECM connector and body ground, when each of the SET/COAST, RESUME/ACCEL and CANCEL is turned ON. See CONNECTOR IDENTIFICATION . See INSPECTING ECM CONNECTOR E4 TERMINAL NO. 31 & BODY GROUND VOLTAGE  table. If the results are OK, go to the next step. If the results are not good, proceed to the next circuit inspection of the symptom. See PROBLEM SYMPTOM INDEX  table.
    INSPECTING ECM CONNECTOR E4 TERMINAL NO. 31 & BODY GROUND VOLTAGE

    Switch Position Voltage
    Neutral 10-16
    RES/ACC 2.4-3.8
    SET/COAST 4.7-6.9
    CANCEL 6.9-9.8
  2. Check the control switch continuity. Remove the steering wheel pad. See DRIVER-SIDE AIR BAG MODULE under REMOVAL & INSTALLATION in AIR BAG RESTRAINT SYSTEMS article. Disconnect the control switch connector. Measure the resistance between terminals No. 4 and 5 of the control switch connector when the control switch is operated. See CONNECTOR IDENTIFICATION . See INSPECTING CRUISE CONTROL SWITCH CONTINUITY  table. If the results are OK, go to the next step. If the results are not good, replace the control switch.
    INSPECTING CRUISE CONTROL SWITCH CONTINUITY

    Switch Position Resistance (Ohms)
    Neutral No Continuity
    RES/ACC 220-260
    SET/COAST 600-660
    CANCEL 1500-1600
  3. Check the main switch continuity. Remove the steering wheel pad. See DRIVER-SIDE AIR BAG MODULE under REMOVAL & INSTALLATION in AIR BAG RESTRAINT SYSTEMS article. Disconnect the control switch connector. Check the continuity between terminals No. 4 and 5 of the control switch connector when the main switch is held ON and OFF. See CONNECTOR IDENTIFICATION . See INSPECTING CRUISE MAIN SWITCH CONTINUITY  table. If the results are OK, go to the next step. If the results are not good, replace the control switch.
    INSPECTING CRUISE MAIN SWITCH CONTINUITY

    Switch Position Tester Connection Specified Condition
    OFF ..... No Continuity
    Hold ON 4 - 5 Continuity
  4. Check the harness and connector between the ECM and cruise control switch, cruise control switch and body ground. If the results are OK, go to the next step. If the results are not good, repair or replace the harness or connector.
  5. Check the cruise control indicator light. See INSTRUMENT PANEL article. If the results are OK, check and replace the ECM. See ENGINE CONTROL MODULE (ECM) . If the results are not good, replace the combination meter. See INSTRUMENT PANEL article.
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