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Chart B-6, IPC-To-Cps Power/Ground Problem

You are at this chart because odometer, with key on, read all 8's or was blank, the high beams would not cycle, but courtesy light came on when switch was activated. These symptoms indicate Instrument Panel Cluster (IPC) has lost 12-volt power feed or ground with Central Power Supply (CPS).

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Checking CCDIC display indicates whether IPC has ground.
  2. Disconnecting IPC and checking resistance in circuit No. 801A determines if fault is due to IPC, wiring and terminals, or the CPS.
  3. This checks if 12 volts is available from the CPS. If not, fault is due to wiring or CPS.
  4. With 12 volts available from CPS, this checks if fault is due to IPC or flex circuit between transition block and IPC.
Fig 1: Chart B-6, Schematic, IPC-To-CPS Power/Ground Problem
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Fig 2: Flow Chart B-6, IPC-To-CPS Power/Ground Problem
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