GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Brakes 🢒 Antilock Brake System 🢒 DTC C0899

Circuit Description

The EBCM is wired to the ignition 1 voltage circuit to indicate the ignition ON/OFF state. The EBCM monitors this voltage to ensure the voltage remains within an acceptable operating range.

Conditions for Running the DTC
    • The ignition is ON.
    • The vehicle speed is greater than 20 km/h (13 mph).

Conditions for Setting the DTC

The EBCM detects low ignition voltage for greater than 224 milliseconds.

Action Taken When the DTC Sets

If equipped, the following actions occur.

    • The EBCM disables ABS/TCS.
    • The ABS indicator turns ON.
    • The traction off indicator turns ON.

Conditions for Clearing the DTC

The conditions for setting the DTC are no longer present and you use the scan tool Clear DTCs function.

Diagnostic Aids

Several charging system related malfunctions may cause this DTC to set intermittently. Refer to the Engine Electrical section for further diagnostic aids.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests if the battery positive voltage circuit can supply adequate power to the system relay.

Step

Action

Values

Yes

No

Schematic Reference: Antilock Brake System Schematics

1

Did you perform the ABS Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2
  1. Use a scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Setting the DTC as specified in the supporting text.

Does the DTC set?

--

Go to Step 3

Go to Diagnostic Aids

3

  1. Turn OFF the ignition.
  2. Disconnect from the EBCM, the harness connector containing the ignition 1 voltage circuit.
  3. Remove the 15A PCM 1 fuse from the fuse panel.
  4. Use a DMM to measure the resistance between the unpowered side of the PCM 1 fuse cavity and the ignition 1 voltage circuit at the EBCM harness connector.

Does the resistance measure within the specified range?

0-0.2ohms

Go to Step 5

Go to Step 4

4

Repair the high resistance in the igniton 1 voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 7

--

5

Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 7

Go to Step 6

6

Important: Following EBCM replacement, use the scan tool to perform the Tire Size/Wheel Base Calibration procedure.

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Did you complete the replacement?

--

Go to Step 7

--

7
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 3

System OK