GM Service Manual Online
For 1990-2009 cars only

Object Number: 247781  Size: MF

Circuit Description

This symptom table checks the following conditions:

    • Checks the state of the ABS indicator to identify a situation in which the ABS indicator did not warn the driver of a system malfunction.
    • The ABS indicator is always ON.

The EBTCM sends a message to the electronic instrument panel cluster (IPC) via the Serial Data Line and the IPC will illuminate the indicator lamp(s).

Diagnostic Aids

Use the lamp test function of the scan tool in order to command the indicator ON while looking for an malfunction in the ABS indicator.

The following conditions may cause an intermittent malfunction:

    • A poor connection
    • Rubbed-through wire insulation
    • A broken wire inside the insulation

Use the Lamp Test function of the Scan Tool in order to turn the indicator on while looking for an intermittent malfunction in the ABS warning indicator circuitry.

Thoroughly inspect any circuitry that may cause the intermittent complaint for the following conditions:

    • Backed out terminals
    • Improper mating
    • Broken locks
    • Improperly formed or damaged terminals
    • Poor terminal-to-wiring connections
    • Physical damage to the wiring harness

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check

2

  1. Turn the ignition switch to the OFF position.
  2. Install a Scan Tool .
  3. Turn the ignition switch to the RUN position.
  4. Use the Scan Tool in order to select SPECIAL FUNCTIONS.
  5. Use the Scan Tool in order to select OUTPUT CONTROLS.
  6. Use the Scan Tool in order to WOW CLUSTER.

Did the amber ABS warning indicator turn on?

--

System OK

Go to Step 3

3

Repair the instrument panel cluster.

Refer to Instrument Cluster, Cell 81, in Electrical Diagnosis.

Is the repair complete?

--

Go to Diagnostic System Check

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