GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Epica 🢒 Brakes 🢒 Antilock Brake System 🢒 DTC C1101

Circuit Description

This circuit is used to monitor the voltage level available to the electronic brake control module (EBCM) . If the voltage rises above a certain level, damage to the system may occur.

Conditions for Setting the DTC

DTC C1101 can only be set if the vehicles speed is greater than 8 kmh (5 mph), if the ignition voltage to terminal 9 and/or 25 is greater than 17 volts for 1 second.

Action Taken When the DTC Sets
    • The solenoid relay opens, removing voltage from the solenoids and pump motor.
    • DTC C1101 is stored.
    • ABS disabled, ABS warning lamp turns ON.

Conditions for Clearing the DTC
    • If the conditions that set the DTC C1101 are no longer present, the DTC may be cleared by using the proper scan tool.
    • The DTC that has not occurred in 100 drive cycles will be cleared from history data.

Diagnostic Aids

Typical causes for DTC C1101 to set:

    • Charging system malfunction
    • Poor connection
    • EBCM malfunction

Step

Action

Values

Yes

No

1

Did you perform the Diagnostic System Check - ABS?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2
  1. Disconnect the electronic brake control module (EBCM) connector.
  2. Turn ON the ignition.
  3. Check the voltage between terminal 4 and 8 of the EBCM connector.
  4. Check the voltage between terminal 4 and 24 of the EBCM connector.

Were the voltages within the specified range?

9.4-17 V

Go to Step 3

Go to Step 4

3
  1. Replace the EBCM. Refer to Brake Pressure Modulator Valve Assembly Replacement .
  2. Check again the diagnostic circuit.

Did you find any problem?

--

Go to Step 1

System OK

4

Check the battery voltage between terminal (+) and (-) of the battery.

Is the voltage within the specified value?

9.4-17 V

Go to Step 6

Go to Step 5

5

Replace the battery. Refer to Battery and Battery Tray Replacement .

Did you complete the replacement

--

Go to Step 1

--

6

Check the resistance between terminal 4 of the EBCM connector and the terminal (+) of the battery.

Is the resistance less than specified?

1 ohms

Go to Step 8

Go to Step 7

7
  1. Check both the terminals mentioned in step 6.
  2. Repair the terminals, as needed.
  3. Check the EBCM connector and wiring harness.
  4. Repair or replace the wiring harness as needed.

Did you find and correct the condition?

--

System OK

--

8

Check the resistance between the terminal 8, 24, and G105.

Does the resistance measure less than the specified value?

1 ohms

Go to Step 10

Go to Step 9

9

Repair or replace the EBCM connector or G105.

Did you complete the repair?

--

Go to Step 1

--

10
  1. Connect a voltmeter to the positive and negative terminal of the battery.
  2. Turn OFF all accessories.
  3. Start the engine.
  4. Monitor the voltage on the meter with the engine running at 2,000 RPM for several seconds.
  5. And also check the voltage between the terminal 4 and 8. And also check the voltage between the terminal 4 and 24.

Do the voltages measure less than the specified value?

17 V

Go to Step 1

Go to Step 11

11

Repair the alternator.

Did you complete the repair?

--

Go to Step 1

--