2000 GMC Sierra 4X4

Tiny
JHUGHES
  • MEMBER
  • 2000 GMC SIERRA
  • V8
  • 4WD
  • AUTOMATIC
  • 115,000 MILES
I HAVE A SIERRA AND THE PUSH BUTTON 4 WHEEL DRIVE WENT BLANK NO LIGHT AT ALL, REPLACED THE BUTTON AND WORKED FINE IT LIT UP PUSHED THE BUTTON AND IT SWITCHED IN AND OUT OF 4 WHEEL DRIVE, IT ONLY WORKED THAT ONE TIME THEN WENT DEAD AGAIN NO LIGHT AT ALL. BUT WHEN I TURN MY KEY TO TURN TRUCK ON ALL LIGHT LIGHT UP AND THEN GO OUT LIKE THE SWITCH IS STILL GOOD I HAVE NO CLUE WHAT IS GOING ON PLEASE HELP.
Do you
have the same problem?
Yes
No
Tuesday, October 28th, 2008 AT 1:18 PM

1 Reply

Tiny
DENNYP
  • EXPERT
Have it checked for trouble codes. It sounds like a bad switch.

XTooltipElement
Service Information
2000 GMC Truck GMC K Sierra - 4WD | Sierra, Silverado, Suburban, Tahoe, Yukon (VIN C/K) Service Manual | Driveline/Axle | Preliminary Information | Document ID: 1616894

#PIP3349: 4WD Inoperative DTC U1026 ATC Fuse Open on Light Duty Trucks, Utilities with NVG 236/246 T/case - keywords cold electrical fuse hi4 inoperative lamp light no switch wire - (Mar 1, 2005)

Subject: 4WD Inoperative DTC U1026 ATC Fuse Open on Light Duty Trucks Utilities with NVG 236/246 T/Case

Models:

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

Condition/Concern:
Four wheel drive inoperative and the 4WD switch light will not illuminate. DTC U1026 will set as a current code. During cold ambient temperatures, the 20 amp ATC fuse for circuit 1640 will go open when shifted into hi4 or auto mode.

Possible cause is that the current draw of the encoder motor exceeds 20 amps when shifting into hi4 or auto mode during cold ambient temperatures.

Recommendation/Instructions:
Refer to the applicable year and model service manual or eSI transfer case wiring schematic.

Replace the 20 amp ATC / T-case fuse with a 25 amp fuse.
Replace circuit 1640 (orange wire), 0.8 mm2 (18 gauge) wire with an orange wire with a specification of a 1.0 mm2 (16 gauge) wire.
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.

Models:
(99-02 Chevrolet Silverado) and (98-02 Chevrolet Tahoe) and (98-02 Chevrolet Suburban) and (98-02 Chevrolet Blazer) and (98-02 GMC Sierra) and (98-02 GMC Yukon) and (00-02 GMC Yukon XL) and (98-02 GMC Jimmy) and (99-02 GMC Envoy) and (99-02 Cadillac Escalade)

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these 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 your GM dealer for information on whether your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

© 2008 General Motors Corporation. All rights reserved.

Let me know what codes you have.
Was this
answer
helpful?
Yes
No
Wednesday, October 29th, 2008 AT 4:39 PM

Please login or register to post a reply.

Recommended Guides