GM Service Manual Online
For 1990-2009 cars only

Object Number: 393791  Size: MF
ABS Components
Antilock Brake System Schematics
Power Distribution Schematics
Power Distribution Schematics
Handling Electrostatic Discharge Sensitive Parts Notice

Circuit Description

The electronic brake control relay supplies power to the solenoid valves and pump motor. The electronic brake control relay, located in the EBCM/EBTCM, is activated whenever the ignition switch is in the RUN position and no faults are present. The electronic brake control relay remains engaged until the ignition switch is turned off or a failure is detected.

Conditions for Setting the DTC

DTC C1214 will set anytime the electronic brake control relay is commanded on and the solenoid valve relay voltage is less than 8 volts, and ignition voltage is greater than 10.5 volts.

Action Taken When the DTC Sets

    • A malfunction DTC is stored.
    • ABS/TCS is disabled.
    • ABS/TCS indicators are turned on.

Conditions for Clearing the DTC

    • Condition for DTC is no longer present and scan tool clear DTC function is used.
    • 100 ignition cycles have passed with no DTCs detected.

Diagnostic Aids

    • Possible causes for DTC C1214 to set are:
       - Poor battery conditions or connections.
       - Poor engine ground connections.
       - Poor EBTCM connector/terminal matings.
    • It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.
    • If an intermittent malfunction exists refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.
    • The electronic brake control relay is integral to the EBCM/EBTCM and is not serviceable separately.

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2

  1. Turn the ignition switch to the RUN position, engine off.
  2. Using J 39200 DMM, measure the voltage at the 10A ABS fuse by probing between the fuse test terminals and a good ground.

Is the voltage within the range specified within the value(s) column?

10.0-14.0 V

Go to Step 3

Go to Power Distribution Schematics

3

  1. Turn the ignition switch to RUN position, engine off.
  2. Check the ABS MaxiFuse in the underhood accessory wiring junction block for voltage at each fuse test terminal.

Is the voltage within the range specified within the value(s) column?

10.0-14.0 V

Go to Step 4

Go to Power Distribution Schematics

4

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the EBCM/EBTCM connector.
  3. Connect the J 39700 Universal Pinout Box using the J 39700-99 Cable Adapter to the EBCM/EBTCM harness connector only.
  4. Using J 39200 DMM, measure the resistance between terminal D of J 39700 Universal Pinout Box and a known good ground.

Is the resistance within the range specified in the value(s) column?

0 - 2 ohms

Go to Step 6

Go to Step 5

5

Repair CKT 251A for an open or high resistance. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

6

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the EBCM/EBTCM connector.
  3. Connect the J 39700 Universal Pinout Box using the J 39700-99 Cable Adapter to the EBCM/EBTCM harness connector only.
  4. Using J 39200 DMM, measure for voltage between terminal A of J 39700 the Universal Pinout Box and a known good ground.
  5. Repeat the previous step and check for voltage between terminal B of J 39700 the Universal Pinout Box and a known good ground.

Is the voltage within the range specified within the value(s) column?

10.0-14.0 V

Go to Step 8

Go to Step 7

7

Repair either CKT 1442A or CKT 1442B for an open circuit.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

8

  1. Turn the ignition switch to the RUN position, engine off.
  2. Using J 39200 DMM, measure the voltage between terminals A11 and D of J 39700 Universal Pinout Box.

Is the voltage within the range specified in the value(s) column?

10.0-14.0 V

Go to Step 10

Go to Step 9

9

Repair CKT 1339 for an open or high resistance.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

10

  1. Turn the ignition switch to the OFF position.
  2. Inspect the following components:
  3. • The EBCM/EBTCM
    • The EBCM/EBTCM harness connector
    • The battery and connections
    • The engine ground connections
  4. Inspect the above components for signs of the following conditions:
  5. • Poor terminal contact
    • Damage terminals
    • Terminal corrosion

Are there any signs of poor terminal contact, corrosion or damage terminal(s)?

--

Go to Step 11

Go to Step 12

11

Replace or repair all of the terminals and/or connectors that exhibit signs of poor terminal contact, corrosion or damage terminal(s).

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

12

Replace the EBCM/EBTCM. Refer to Electronic Brake Control Module/Electronic Brake and Track Control Module Replacement .

Is the replacement complete?

--

Go to Diagnostic System Check - ABS

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