GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2006 🢒 Optra - Mexico 🢒 Restraints 🢒 SIR 🢒 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 antilock brake system (ABS) action is disabled during the period of low voltage, and the ABS warning lamp is 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 C0800.

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 ABS Schematics

Connector End View Reference: Antilock Brake System Connector End Views ABS Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - VehicleDiagnostic 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.

Is the fuse open?

--

Go to Step 6

Go to Step 7

6
  1. Turn the ignition to OFF.
  2. Test the RD wires in the antilock brake system (ABS) wiring harness from terminal 1 of C107 at the engine fuse block to terminals 17 and 18 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 F11 in the instrument panel (I/P) fuse block.

Is the fuse open?

--

Go to Step 9

Go to Step 12

9
  1. Replace fuse F11.
  2. Turn the ignition to ON.

Is the fuse open?

--

Go to Step 10

Go to Step 11

10
  1. Turn the ignition to OFF.
  2. Test the PNK wire from fuse F11 to terminal 43 of connector C201, from terminal 62 of connector C202 to terminal 6 of connector C110, and from there to terminal 15 of the EBCM connector.
  3. Repair any short circuit found along this path.

Did you find and correct the condition?

--

Go to Step 25

--

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 from the EBCM.
  2. Turn the ignition to ON.
  3. Test for the presence of battery voltage between ground and terminal 17, and between ground and terminal 18.

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 OG wires between terminals 17 and 18 of the EBCM connector to terminal 1 of connector C107 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 15 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 EF5 in the engine fuse block.

Is the fuse open?

--

Go to Step 16

Go to Step 17

16

Replace fuse EF5.

Did you complete the replacement?

--

Go to Step 25

--

17

  1. Test circuit BN between terminal 15 of the EBCM connector to terminal 6 of connector C110 to terminal 62 of C202, to F11 in the instrument panel (I/P) fuse block.
  2. Test the PK wire from the I/P fuse block to terminal 4, IG1, of the ignition switch.
  3. Test the RD wire from terminal 2, B1, of the ignition switch to terminal 59 of connector C202 to terminal 4 of connector C105 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 16 and 19 of the ABS harness EBCM connector.

Is the resistance equal to the specified value?

0 ohms

Go to Step 19

Go to Step 21

19

Test terminals 15, 16, 17, 18, and 19 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. Test 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 ABS unit.

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