CB-434D, CB-534D, CB-534D Series XW and CB-564D Paving Compactors Caterpillar

Illustration 1	g01174455
CB534D split drum Traction Control System (Attachment)

The electrical components in the Traction Control System (attachment) for the CB534D Split Drum compactors are:

Electronic Control Module (ECM) - Receives input from the speed sensors and the differential lock switch. Outputs control signals to the solenoid valves and the indicator lamp.

Diverter valve solenoids (2 front, 2 rear) - Receive control output signals from the ECM in order to control hydraulic flow to the individual hydraulic propel motors.

Drum speed sensor (2 front, 2 rear) - Provide individual drum speed input to the ECM.

Machine Propel speed sensor - Provide machine speed input to the ECM.

Differential lock switch - Provides operator input to the ECM in order to activate the traction control function.

Differential lock lamp - ECM output to indicate that the traction control system is active when the lamp is illuminated. The ECM will cause the lamp to flash ON and OFF when a problem is detected in the system.

Symptom Related Problems:

Problem

When the machine is turning during propel, the motion is not smooth.

Probable cause

• The differential lock control switch is activated or is stuck in the ON position.

• A drum speed sensor is sending an intermittent signal to the ECM.

• A flow control valve is stuck in the closed position.

• There is an internal problem in the propel motor.

Problem

The traction control system does not appear to be working when activated (drum spin out).

Probable cause

• The differential lock control switch is activated or is stuck in the ON position.

• A drum speed sensor has failed.

• Loss of the power supply to the ECM

System Diagnostics

The traction control ECM will use the differential lock indicator lamp on the dashboard in order to alert the operator that there is a problem with the system. Under normal conditions, the ECM will steadily illuminate the differential lock indicator lamp when the traction control function is activated. When the ECM detects a problem in the system, the differential lock indicator lamp on the dash will flash ON and OFF.

The traction control ECM is located at the front of the machine under the cover plate that is above the front drums. The ECM will indicate the status of the system using the four LED indicators that are located on the front panel of the ECM in the following manner:

System OK - Green LED's blink following the rotation of the drums.

System malfunction - Orange or red LED's illuminate in a particular pattern in order to indicate the problem component.

Illustration 2	g01174600
Traction Control ECM with four diagnostic LED indicators

When a system malfunction occurs, the possible diagnostic LED pattern combinations and the associated components are listed in Table 1.