Hummer H2. Manual — part 757

Wheel Terminal Identification Speed Sensor (WSS) - LR

Wheel Terminal Identification Speed Sensor (WSS) - RF

B

YE

873

Left Front Wheel Speed Sensor Low Reference

Connector Part Information

z

12162193

z

2-Way F Metri-Pack 150.2 Series Sealed Pull To Seat (BK)

Pin

Wire Color

Circuit No.

Function

A

BK

884

Left Rear Wheel Speed Sensor Signal

B

RD

885

Left Rear Wheel Speed Sensor Low Reference

2004 Hummer H2

2004 BRAKES Anti-Lock Brake System - Hummer H2

Wheel Terminal Identification Speed Sensor (WSS) - RR

Connector Part Information

z

12052641

z

2-Way F Metri-Pack 150 Series (BK)

Pin

Wire Color

Circuit No.

Function

A

D-GN

872

Right Front Wheel Speed Sensor Signal

B

TN

833

Right Front Wheel Speed Sensor Low Reference

2004 Hummer H2

2004 BRAKES Anti-Lock Brake System - Hummer H2

DIAGNOSTIC INFORMATION AND PROCEDURES

DIAGNOSTIC STARTING POINT - ANTI-LOCK BRAKE SYSTEM

Connector Part Information

z

12162193

z

2-Way F Metri-Pack 150.2 Series Sealed Pull To Seat (BK)

Pin

Wire Color

Circuit No.

Function

A

BN

882

Right Rear Wheel Speed Sensor Signal

B

WH

883

Right Rear Wheel Speed Sensor Low Reference

2004 Hummer H2

2004 BRAKES Anti-Lock Brake System - Hummer H2

Begin the system diagnosis with Diagnostic System Check - ABS . The Diagnostic System Check will provide
the following information:

z

The identification of the control modules which command the system

z

The ability of the control modules to communicate through the serial data circuit

z

The identification of any stored diagnostic trouble codes (DTCs) and their status

The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and
where the procedure is located.

DIAGNOSTIC SYSTEM CHECK - ABS

Circuit Description

The ABS Diagnostic System Check is an organized approach to identify problems associated with the EBCM.
This check must be the starting point for any EBCM complaint, and will direct you to the next logical step in
diagnosing the complaint. The EBCM is a very reliable component and is not likely the cause of the
malfunction. Most system complaints are linked to faulty wiring, connectors, and occasionally to components.
Understanding the ABS system and using the tables correctly will reduce diagnostic time and prevent
unnecessary parts replacement.

Test Description

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

2: Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a
total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular
condition.

4: The presence of DTCs which begin with "U" indicate some other module is not communicating. The
specified procedure will compile all the available information before tests are performed.

Diagnostic System Check - ABS

Step

Action

Yes

No

1

Install a scan tool.
Does the scan tool power up?

Go to Step 2

Go to Scan Tool Does Not

Power Up in Data Link

Communications

2

1. Turn ON the ignition, with

the engine OFF.

2. Attempt to establish

communications with the
following control modules.

z

Electronic brake
control module
(EBCM)

z

Powertrain control

2004 Hummer H2

2004 BRAKES Anti-Lock Brake System - Hummer H2