GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 Spark 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC C0800

Circuit Description

Proper operation of the electronic brake control module (EBCM) requires a certain minimum voltage. The EBCM monitors the ignition feed circuit to determine if the voltage falls below a minimum level.

This test inspects for battery output, proper grounding, blown fuses, faulty ignition switch, and problems in the circuitry.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0800 Battery Voltage Out Of Range

Conditions for Running the DTC
    • Vehicle speed is greater than 6 km/h (4 mph) with the brake pedal not applied.
        OR
    • Vehicle speed is greater than 15 km/h (9 mph) and the brake pedal is actuated.

Conditions for Setting the DTC
    • The battery is defective.
    • There is a defective ground connection.
    • A connector is damaged.
    • A wire is broken or shorted.
    • A fuse is blown.
    • The ignition switch is malfunctioning.

Action Taken When the DTC Sets

The following actions occur:

    • The antilock brake system (ABS) is disabled during the period of low voltage.
    • The ABS warning indicator turns ON for the remainder of the ignition cycle.

If the failure is intermittent, the EBCM will enable the system at the next ignition cycle and set a history DTC.

Conditions for Clearing the DTC

The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.

Diagnostic Aids

It is very important to perform a thorough inspection of the wiring and the connectors. Failure to do so may result in misdiagnosis, causing part replacement with a reappearance of the malfunction.

Test Description

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

  1. This step determines whether there is voltage at the battery and at the high current source.

    2.

  2. This step tests for voltage at the ignition 1 source.

    3.

  3. This step begins the test for voltage at the EBCM end of the ABS harness.

    4.

  4. This step inspects for a defective ground connection.

    5.

  5. This is an inspection for a defective EBCM connector.

Step

Action

Values

Yes

No

Schematic Reference: Antilock Brake System Schematics

Connector End View Reference: Component Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Measure the voltage at the battery.

Does the voltage measure within the specified value?

11-14 V

Go to Step 4

Go to Step 3

3

Charge or replace the battery as required.

Did you complete the action?

--

System OK

--

4

Inspect fuse EF2 in the engine fuse block.

Is the fuse open?

--

Go to Step 5

Go to Step 8

5
  1. Replace fuse EF2.
  2. Turn the ignition to ON.

Dopes the fuse blow?

--

Go to Step 6

Go to Step 7

6
  1. Turn the ignition to OFF.
  2. Test the RED/BLK wires in the antilock brake system (ABS) wiring harness from terminal 1 and 2 of C104 at the engine fuse block to terminals 14 and 1 of the electronic brake control module (EBCM) connector.
  3. Repair any short circuit found along this path.

Did you find and correct the condition?

--

Go to Step 25

--

7
  1. Turn the ignition switch to OFF.
  2. Install the scan tool.
  3. Clear all diagnostic trouble codes (DTCs).
  4. Road test the vehicle.

Does DTC C0800 reset?

--

Go to Step 25

--

8

Inspect fuse F14 in the instrument panel (I/P) fuse block.

Is the fuse open?

--

Go to Step 9

Go to Step 12

9
  1. Replace fuse F14.
  2. Turn the ignition to ON.

Does the fuse blow?

--

Go to Step 10

Go to Step 11

10
  1. Turn the ignition to OFF.
  2. Test the PNK/RED wire from fuse F14 to terminal 8 of connector C103, to terminal 20 of the EBCM connector.
  3. Repair any short circuit found along this path.

Did you find and correct the condition?

--

System OK

--

11
  1. Turn the ignition switch to OFF.
  2. Install the scan tool.
  3. Clear all DTCs.
  4. Road test the vehicle.

Does DTC C0800 reset?

--

Go to Step 25

--

12

  1. Disconnect the EBCM connector.
  2. Turn the ignition to ON.
  3. Test for the presence of battery voltage between ground and terminal 14, and between ground and terminal 1.

Does the voltage measure within the specified range?

11-14 V

Go to Step 14

Go to Step 13

13
  1. Turn the ignition switch to OFF.
  2. Test the orange wires between terminals 14 and 18 of the EBCM connector to terminal 1 and 2 of connector C104 at the engine fuse block.
  3. Repair the open in this circuit.

Did you find and correct the condition?

--

Go to Step 25

--

14

Measure the voltage between ground and terminal 20 of the EBCM connector.

Does the voltage measure within the specified range?

11-14 V

Go to Step 18

Go to Step 15

15
  1. Turn the ignition switch to OFF.
  2. Inspect fuse Ef2 in the engine fuse block.

Is the fuse open?

--

Go to Step 16

Go to Step 17

16

Replace fuse Ef2.

Did you complete the replacement?

--

Go to Step 25

--

17

  1. Test the circuit between terminal 20 of the EBCM connector and terminal 8 of connector C103, and F14 in the instrument panel (I/P) fuse block.
  2. Test the wire from the I/P fuse block to terminal 4, IG1, of the ignition switch.
  3. Test the wire from terminal of the ignition switch to the terminal of connector C102 at the engine fuse block.
  4. Repair the open in the wiring or possibly bad connector terminal, or defective ignition switch.

Did you find and correct the condition?

--

Go to Step 25

--

18
  1. Turn the ignition to OFF.
  2. Measure the resistance between ground and terminals 13 and 26 of the EBCM connector.

Is the resistance equal to the specified value?

0 Ω

Go to Step 19

Go to Step 21

19

Test terminals 20, 13, 14, 1, and 26 of the EBCM connector.

Is there a defective terminal?

--

Go to Step 20

Go to Step 22

20

Repair the defective terminal or replace the connector or wiring harness as required.

Did you find and correct the condition?

--

Go to Step 25

--

21

Repair the defective ground connection.

Did you complete the repair?

--

Go to Step 25

--

22
  1. Install the scan tool.
  2. Clear all DTCs.
  3. Road test the vehicle.

Does DTC C0800 set?

--

Go to Step 24

Go to Step 23

23
  1. Inspect the wiring harness and connectors for causes of intermittent problems.
  2. Repair any intermittent problem found.

Did you find and correct the condition?

--

Go to Step 25

--

24

Replace the EBCM. Refer to Brake Pressure Modulator Valve Assembly Replacement.

Did you complete the replacement?

--

Go to Step 25

--

25
  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 2

System OK