GM Service Manual Online
For 1990-2009 cars only

Object Number: 412173  Size: MF
ABS Components
Brake Pressure Modulator Valve (BPMV)

Circuit Description

The pump motor is an integral part of the BPMV, while the electronic brake control relay is integral to the EBCM. The relay supplies power to the solenoid valves and pump motor. The relay activates when the ignition is turned ON. Power is available to the solenoid valves and pump motor through the relay via the battery supply circuit. The relay remains engaged until you turn OFF the ignition.

Conditions for Running the DTC

    • The pump motor has been commanded OFF for 1 second.
    • The switched system battery voltage is greater than 9 volts.

Conditions for Setting the DTC

One of the following conditions occur:

    • Voltage across the pump motor is greater than 10.16 volts for 0.2 seconds.
    • The pump motor low side voltage is less than 2.7 volts for 0.2 seconds.

Action Taken When the DTC Sets

If equipped, the following actions occur:

    • The EBCM disables the ABS for the duration of the ignition cycle.
    • The ABS indicator turns ON.

Conditions for Clearing the DTC

    • The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used.
    • 100 drive cycles pass with no DTCs detected. A drive cycle consists of starting the vehicle, driving the vehicle over 16 km/h (10 mph), stopping and then turning the ignition OFF.

Diagnostic Aids

This DTC determines if there is a short to ground in the pump motor control circuit.

    • 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 Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step tests the pump motor circuits of the BPMV for a short to the housing of the BPMV. The wiring through the BPMV should not be repaired.

Step

Action

Value(s)

Yes

No

1

Did you perform the ABS Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2

  1. Turn OFF the ignition
  2. Disconnect the EBCM harness connector
  3. Connect the J 39700 universal pinout box using the J 39700-99 cable adapter to the EBCM harness connector only.
  4. Test both ground circuits of the EBCM including ground G200 for a high resistance or an open.

Did you find and correct the condition?

--

Go to Step 6

Go to Step 3

3

  1. Remove the EBCM from the BPMV.
  2. Measure the resistance from both pump motor control circuits of the BPMV to the housing of the BPMV.

Does the resistance measure less than the specified value?

5 ohms

Go to Step 4

Go to Step 5

4

Replace the BPMV. Refer to Brake Pressure Modulator Valve Replacement .

Did you complete the repair?

--

Go to Step 6

--

5

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

Did you complete the repair?

--

Go to Step 6

--

6

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

Does the DTC reset?

--

Go to Step 2

System OK