2001-2004 U/X Van Intermittent ABS Light On - keywords C1227 C1228 C1234 C1235 lamp MIL wire

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in the PI.

A customer may comment of an intermittent ABS indicator light illuminating. There may be ABS codes of C1234, C1235, C1227 and/or C1228 set in history.

The replacement of wheel speed sensors and/or EBTCM module may prove ineffective. The technician should look closely at three specific areas for wiring chaffing concerns. The three areas of possible chaffing are:

1. The main engine harness possibly contacting the mass air flow (MAF) sensor housing.
2. The wire harness in contact with the transmission shifter cable bracket. The bracket is located on the top of the transmission below the brake booster area.
3. The wire harness from connector C101 is being routed between the booster and the braided steel brake lines from the DBC-7 modulator.

Note: These harnesses may be viewed in SI under the following Document ID numbers:

2001 - Document ID # 742788

2002 - Document ID # 779674

2003 - Document ID # 838087

2004 - Document ID # 838087

The correction would be to repair any wiring concern located in these areas and reroute or protect the harness with conduit in the contact areas.

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

(2001-2004 Chevrolet Venture) and (2001-2004 Oldsmobile Silhouette) and (2001-2004 Pontiac Montana)