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Chart B6 - IPCTO-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 volts power 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 the IPC and checking resistance in circuit No. 801A determines if fault is due to the IPC, wiring and terminals, or the CPS.
  3. This step 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 step checks if fault is due to IPC or flex circuit between transition block and IPC.
Fig 1: Flow Chart B6, IPC To-CPS Power/Ground Problem
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Fig 2: Flow Chart B6, IPC To-CPS Power/Ground Problem
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