For 1990-2009 cars

# DAY TIME RUNNING LIGHT MODULE PREVENTION OF FAILURES

#### SUBJECT: INFORMATION/PROTECTING THE DAYTIME RUNNING LIGHT MODULE

#### VEHICLES AFFECTED: 1989-1991 CANADIAN VEHICLES

#### CONDITION:

Comments have been received that after an electrical repair, the daytime running lights module (DRLM) is damaged and inoperative.

#### CAUSE:

This condition could result from not connecting the negative battery cable before turning on the ignition switch which allows transient current to flow through the (DRLM).

#### CORRECTION:

Always make sure the negative battery cable is connected and tight after any electrical repair before turning on the ignition switch. This will prevent any transient current flow through the (DRLM) or any other electronic modules the vehicle is equipped with. The absence of proper grounding can increase electrical transient susceptibility and lead to reduced component life and/or damage.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.