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Test TD: Temperature Gauge Always Indicates Cold (Bottom Bar Of Display Illuminated)

  1. Check Temperature Gauge Wiring

    Disconnect temperature sending unit connector located at thermostat housing. Connect jumper wire between ground and temperature sending unit connector. Turn ignition switch to RUN position. Temperature gauge should have top 2 and bottom 2 segment bars of temperature gauge illuminated and ISO thermometer symbol should be illuminated or blinking. If temperature gauge is working as specified, remove jumper wire, and go to step  3 . If temperature gauge is not working as specified, go to next step.
  2. Check Wiring At Cluster

    Disconnect negative battery cable. Remove Electronic Instrument Cluster (EIC). See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. Disconnect temperature sending unit connector. Connect jumper wire from temperature sending unit connector terminal to ground. Using DVOM, check for continuity between EIC connector "B" terminals No. 4 (Red/White wire) and No. 8 (Black/White wire). If continuity exists, replace EIC. If continuity does not exist, repair open in Red/White wire between temperature sending unit and EIC.
  3. Check Sender

    Warm engine to normal operating temperature. Using DVOM, measure resistance between ground and terminal of temperature sending unit. If reading is less than 8000 ohms, replace EIC. See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. If reading is 8000 ohms or more, go to next step.
  4. Check Cooling System

    Check cooling system for proper operation: thermostat, belts, hoses and coolant level. If problem with cooling system is indicated, repair as required and retest. If cooling system is okay, replace temperature sending unit.