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Test TA, Display Not Illuminated Too Dim Or Totally Black

  1. Verifying Condition: Turn ignition on. Turn headlights off. Check instrument cluster displays. If only one or two displays are working properly, replace instrument cluster. Install door pillar sticker to indicate instrument cluster has been replaced. If all displays are too dim, proceed to step 11). If all displays are blank, proceed to step 2)
  2. Verifying Warning Chime Module Operation: Turn ignition on. Press any button on instrument cluster controls. Listen for beep tone from warning chime module when button is pressed. If beep tone is heard, proceed to step 10). If no beep tone is heard, proceed to step 3).
  3. Checking Fuses: Check for defective No. 1 fuse (15-amp) in fuse panel below instrument panel, left of steering column. Fuse is in lower right corner of fuse panel. Check for defective No. 4 fuse (10-amp) in fuse panel below instrument panel, left of steering column. Fuse is in lower left corner of fuse panel.
  4. If both fuses are okay, proceed to step 6). If fuses are blown, proceed to step 5).
  5. Checking For Shorted Circuit: Turn ignition off. Disconnect negative battery cable. Using ohmmeter, check for short to ground at No. 1 and No. 4 fuses. If no short exists, proceed to step 12). If short exists, repair as necessary.
  6. Checking Voltage At Fuses: Reconnect negative battery cable. Using voltmeter, measure voltage from No. 1 and No. 4 fuses to ground. If voltage is greater than 9 volts, proceed to step 7). If voltage is less than 9 volts, repair defective power supply or fuse holder.
  7. Checking Voltage At Instrument Cluster: Turn ignition off. Remove instrument cluster. See INSTRUMENT CLUSTER R & I  . Turn ignition on. Note instrument cluster connector identification. See Figure .
  8. Using voltmeter, measure voltage at following terminals of instrument cluster connectors:
    • Connector C2-1, Pin No. 5 (Light Blue/Pink wire) Battery Voltage with ignition on.
    • Connector C2-1, Pin No. 3 (Light Green/Purple wire) Battery Voltage all the time.
    • Connector C1, Pin No. 2 (Light Blue/Pink wire) Battery Voltage with ignition on.

    If voltage exists, replace instrument cluster. If no voltage exists, check wiring circuits of No. 1 and No. 4 fuses from fuse panel to instrument cluster.

  9. Using ohmmeter, check continuity between instrument cluster connector C1, pin No. 1 (Pink/Orange or Black/Light Blue wire), C2-1, pin No. 4 (Pink/Orange or Black/Light Blue wire) and battery ground. If no continuity exists, check for defective wiring and ground circuit.
  10. Checking Instrument Cluster Connections: Ensure all connections are properly locked on instrument cluster and no terminals are damaged. Repair defective connections if necessary. If all connections are okay, proceed to step 7), and check for power supply to instrument cluster.
  11. Checking Rheostat Output: Remove instrument cluster. See INSTRUMENT CLUSTER R & I  . Turn ignition on. Using voltmeter, check rheostat output at instrument cluster connector C2-2, pin No. 29 (Light Blue/Red wire) with headlights off. If voltage is less than 3 volts, replace instrument cluster. Install door pillar sticker to indicate instrument cluster has been replaced. If voltage is greater than 3 volts, replace rheostat.
  12. Checking For Short In Instrument Cluster: Turn ignition off. Remove instrument cluster. See INSTRUMENT CLUSTER R & I  . Using ohmmeter, check for continuity between following pins of instrument cluster:
    • Connector C1 (pin No. 2), C2-1 (pin No. 5), C2-1 (pin No. 3) to C1 (pin No. 1) or C2-1 (pin No. 4). For determining wire colors on mating surface, refer to the CONNECTOR PIN WIRE COLORS  table.
    CONNECTOR PIN WIRE COLORS

    Connector & Pin Number Wire Color
    Connector C1, Pin No. 1 Pink/Orange
    Connector C1, Pin No. 2 Light Blue/Pink
    Connector C2-1, Pin No. 3 Light Green/Purple
    Connector C2-1, Pin No. 4 Pink/Orange
    Connector C2-1, Pin No. 5 Light Blue/Pink
  13. If continuity exists for any measurement, replace instrument cluster and fuses. Install door pillar sticker to indicate instrument cluster has been replaced. If continuity does not exist, replace fuse, and install instrument cluster.
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