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CMTC Test 3A - CMTC Displays OC

NOTE: Perform CMTC TEST 1A  before proceeding with this test. For connector terminal ID, see CONNECTOR IDENTIFICATION  and WIRING DIAGRAM. Perform TEST VER-1A  after each repair.
CAUTION: Always turn ignition switch to OFF position prior to disconnecting any module connector. Ensure all connectors are clean and tight.
  1. Disconnect ambient temperature sensor connector. See Figure under CMTC TEST 2A  . Connect jumper wire between ambient temperature sensor connector terminals. Turn ignition on, engine off. Observe CMTC display. If CMTC displays OC, replace ambient temperature sensor. If CMTC does not display OC, go to next step.
  2. Turn ignition off. Disconnect Body Control Module (BCM) Black 24-pin connector. BCM is located under left side of dash. Using scan tool in ohmmeter mode, measure resistance at terminal No. 2 (Dark Green/Red wire) on ambient temperature sensor connector. If resistance is more than 5 ohms, repair open Dark Green/Red wire. If resistance is 5 ohms or less, go to next step.
  3. Using scan tool in ohmmeter mode, measure resistance at terminal No. 1 (Light Green/White wire) on ambient temperature sensor connector. If resistance is more than 5 ohms, repair short in Light Green/White wire. If resistance is 5 ohms or less, replace BCM.