Chart B, Loss Of Serial Data (Non-CRT Equipped)

IPC indicates loss of serial data communication by displaying message ELECTRICAL PROBLEM. All other segments are blank. If display is fully illuminated and ELECTRICAL PROBLEM message is displayed, enter diagnostics, and go to appropriate code chart. DO NOT use CHART A. Loss of serial data communications can occur for following reasons:

• Short to ground anywhere in circuit No. 800.
• Short to voltage anywhere in circuit No. 800.
• Two opens in circuit No. 800.
• Internal BCM or IPC fault.
• Open in ECCP ground circuit.
  NOTE: Test numbers refer to numbers on diagnostic chart.
  1. This step checks to see if ECCP has lost data communication along with IPC.
  2. Since IPC has lost data communications, shorting terminal "M" at ALDL connector should not remove data communications from ECCP. If data communications from ECCP is not received, IPC is receiving data but unable to communicate due to poor connection or internal problem.

Fig 1: Chart B, Schematic, Loss of Serial Data (Non-CRT Equipped)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Flow Chart B, Loss of Serial Data (Non-CRT Equipped)

Courtesy of GENERAL MOTORS CORP.