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Test Ta: Display Not Illuminated; Too Dim, Or Totally Black

  1. Check Other Displays

    Turn ignition switch to RUN position. Turn headlights off. Check display for illumination. If other displays are too dim or black, go to next step. If other displays are working properly, go to step  7 .

  2. Verify Module Operation

    Ensure ignition switch is in RUN position. Press any cluster control button switch. Listen for cluster warning tones from warning chime module when button is pressed. Monitor speedometer, gauges and fuel computer displays for appropriate information and that messages are displayed in a normal pattern. If illumination is too dark, shine light into Electronic Instrument Cluster (EIC). If normal information display patterns are not presented, go to next step. If normal information messages are displayed, go to step  7 .

  3. Check Fuse

    Check for blown memory (5-amp) fuse at underhood fuse block. If fuse is blown, go to next step. If memory (5-amp) fuse is not blown, go to step  5 .

  4. Check For Short In Circuit 797

    Before replacing fuse, turn ignition switch to OFF position. Disconnect negative battery cable. Connect DVOM between ground and both terminals of memory (5-amp) fuse holder. If reading is 10 k-ohms or more, replace fuse. If reading is less than 10 k-ohms, repair short to ground in circuit 797 (Light Green/Purple wire), as necessary.

  5. Check For Power At Fuse

    Using DVOM, measure voltage between ground and Light Green/Purple wire terminal of memory fuse holder. If reading is 10 volts or more, go to next step. If reading is less than 10 volts, repair open or high resistance in Light Green/Purple wire. See WIRING DIAGRAMS  .

  6. Check For Power At Cluster

    Turn ignition switch to OFF position. Remove EIC. See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. Reconnect negative battery cable. Turn ignition switch to RUN position. Using DVOM, measure voltage at EIC connector "B" terminals No. 7 (Light Green/Purple wire) and No. 9 (Purple/Orange wire). Battery voltage should exist at both terminals. Using DVOM, check continuity between ground and EIC connector "B" terminal No. 8 (Black/White wire). Continuity to ground should exist. If voltage or continuity does not exist as described, repair affected circuits as necessary. If voltage and continuity exist as described, replace EIC.

  7. Check Bulbs & Light Bar

    Remove EIC. See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. Remove light bar. Check light bulbs and light bar circuit. If light bulbs are not burned-out, go to next step. If light bulbs are burned-out or circuit is defective, replace bulb or defective light bar as necessary.

  8. Verify Harness Continuity

    Using DVOM, check continuity of circuit 464 (Black/Pink wire) between EIC connector "B" terminal No. 1 and EIC connector "A" terminal No. 16. See Figure . If continuity does not exist, repair open in circuit 464 (Black/Pink wire). If continuity exists, go to next step.

  9. Check Power To Bulbs

    Turn ignition switch to RUN position. Using DVOM, measure voltage between EIC connector "A" terminal No. 15 (Purple/Orange wire) to EIC connector "B" terminal No. 8 (Black/White wire). See Figure . If voltage is 10 volts or more, replace EIC. See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. If voltage is less than 10 volts, repair open in Purple/Orange wire between EIC connector "A" and memory (5-amp) fuse in underhood fuse block.
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