GM Service Manual Online
For 1990-2009 cars only

Circuit Description

When the ignition switch is in the UNLOCK position, certain Class 2 messages do not transmitt. The instrument cluster panel (IPC) suspends the operation of the indicators and the gauges that are dependent on these messages until the ignition switch is no longer in the UNLOCK position. Refer to Cluster Power-Up Function Check Table for Class 2 controlled indicators in the UNLOCK position.

Conditions for Setting the DTC

If the voltage at the IPC connector terminal A10 is less than a calculated voltage for more then 1 second and the engine is running.

Conditions for Clearing the DTC

    • The voltage at terminal A10 is greater than the 75 percent of battery positive voltage.
    • A history DTC will clear after 100 consecutive fault free ignition cycles.
    • History and Current DTC(s) can be cleared by using the scan tool.

Diagnostic Aids

    • An intermittent problem may be caused by a poor connection, break in the wire insulation exposing the internal wire, or a wire that is broken inside the insulation.
    • If the ignition 0 voltage is low at the IPC connector pin A10 and the engine is not running, the IPC odometer and PRNDL displays will not be illuminated and the IPC will not communicate with the scan tool. The season odometer will display if the tripometer switch is pressed. The IPC will communicate with the scan tool until the tripometer switch is released.
    • DTC 1367 could be read by the scan tool as a history code if the fuse has been recently replaced in the CKT 1020 CKT, or an open or short to ground has been repaired in the CKT 1020 CKT.

Test Description

Step number(s) below refer to the same step number(s) in the Diagnostic Table

2. This step checks the ignition 0 circuit to the IPC for intermittent connections.

Step

Action

Value(s)

Yes

No

1

Was the instrument panel cluster (IPC) system check performed?

--

Go to Step 2

Go to Instrument Cluster System Check

2

  1. Disconnect the instrument panel cluster (IPC).
  2. Inspect for intermittent connection at pin A10 of the IPC connector or an intermittent open or short to ground in the CKT 1020 CKT.

Is the intermittent connection present?

--

Go to Step 3

Go to Step 4

3

Repair the intermittent connection.

Is the repair complete?

--

Go to Step 4

--

4

Clear the IPC DTCs using a scan tool. Refer to Clearing DTCs .

Did you clear the DTCs?

--

Go to Instrument Cluster System Check

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