S10/T10 P/U 4WD V6-4.3L VIN X (1996)
Technical Service Bulletin # 99-041
Date: 000501
Recall - ABS Front Axle Signal Malfunction
File in: Product
Section: Campaigns
Bulletin No: 99041
Dates: May, 2000
SUBJECT:
99041 - INCORRECT FRONT AXLE STATUS SIGNAL TO EBC4 ABS
MODELS:
1991-1996 CHEVROLET AND GMC 4WD T UTILITIES
1994-1996 CHEVROLET AND GMC 4WD T PICKUP TRUCKS
DUE TO THE AVAILABILITY OF PARTS, THIS CAMPAIGN WILL BE ADMINISTERED IN PHASES. YOU WILL RECEIVE A DEALER
LISTING AS PHASES ARE RELEASED.
CONDITION
General Motors has decided that a defect which relates to motor vehicle safety exists in certain 1991-1996 Chevrolet and GMC 4WD T utilities and
1994-1996 Chevrolet and GMC 4WD T pickup trucks. Some of these vehicles exhibit a condition in which a switch that signals the antilock brake
system (ABS) module when the vehicle is in four-wheel drive (4WD) may malfunction. The ABS module is designed with two different operating
algorithms; one for two-wheel drive (2WD) operation and another for 4WD drive operation. This allows the ABS system to compensate for the braking
torque applied tot he rear wheels through the drivetrain when the vehicle is in 4WD drive. When the vehicle is in 2WD, a malfunctioning switch may
send an incorrect signal tot he ABS module. If this occurs during an ABS stop, a somewhat longer stopping distance could result. If this occurred when
minimum stopping distance was required, it could result a vehicle crash.
CORRECTION
Dealers are to install a new transfer case selector switch, wiring harness, and an additional switch to ensure that the ABS receives the 4WD signal only
when the drivetrain is in 4WD.
VEHICLES INVOLVED
