Pinpoint Test Q: The ABS Warning Indicator Is Never/Always On

Instrumentation, Message Center and Warning Chimes

Pinpoint Test Q: The ABS Warning Indicator Is Never/Always On

Normal Operation

The ABS module provides ABS status to the Instrument Panel Cluster (IPC) over the High Speed Controller Area Network (HS-CAN) communication bus. If a fault condition exists in the ABS, the ABS module sends the IPC (Instrument Panel Cluster) a command to either flash the ABS warning indicator or to turn it on. If the ABS status message is missing for less than 5 seconds, the IPC (Instrument Panel Cluster) defaults the ABS warning indicator to the last on/off state, based upon the last known good ABS status message received. If the ABS status message is missing for more than 5 seconds, the IPC (Instrument Panel Cluster) sets DTC U0121:87 and defaults the ABS warning indicator on.

This pinpoint test is intended to diagnose the following:

- ABS module

- IPC (Instrument Panel Cluster)

PINPOINT TEST Q : THE ABS WARNING INDICATOR IS NEVER/ALWAYS ON

Q1 CARRY OUT THE IPC (Instrument Panel Cluster) INDICATOR LAMP CONTROL ACTIVE COMMAND USING THE SCAN TOOL

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: IPC (Instrument Panel Cluster) DataLogger.

- Select the IPC (Instrument Panel Cluster) ABS warning indicator (ABS_LAMP) active command on then off. Observe the ABS warning indicator.

Does the ABS warning indicator illuminate when commanded on, and turn off when commanded off?

Yes
GO to Q2.

No
INSTALL a new IPC (Instrument Panel Cluster). REFER to Instrument Panel Cluster (IPC) . TEST the system for normal operation.

Q2 RETRIEVE THE RECORDED DTCs FROM THE IPC (Instrument Panel Cluster) SELF-TEST

- Check for recorded DTCs from the IPC (Instrument Panel Cluster) self-test.

Are any ABS module DTCs recorded?

Yes
For DTC U0121:87, GO to Pinpoint Test AR Pinpoint Test AR: DTC U0121:87.

For all other DTCs, REFER to DTC Charts Instrumentation, Message Center and Warning Chimes.

No
GO to Q3.

Q3 RETRIEVE THE RECORDED DTCs FROM THE ABS MODULE SELF-TEST

- Check for recorded DTCs from the ABS module self-test.

Are any DTCs recorded?

Yes
REFER to Antilock Brakes / Traction Control Systems.

No
INSTALL a new ABS module. TEST the system for normal operation.