Why is the service 4WD light on on my GMC?

Some customers may comment that the Service 4WD light is on, the 4WD system is inoperative, the 4WD switch indicator lights are blinking or that a grinding noise is heard from the front axle.

Why does my GMC Sierra 1500 say service 4WD?

Having similar issues as above, had to drive the truck in 4wd high for a short period of time without the rear drive shaft, heard a clunk and the service 4wd message came on, the front drive shaft quit which left me stranded.

Why is my service 4WD indicator not working?

If the wires are broken, the actuator won’t operate and the actuator won’t move. If it does not move to the proper position, the buttons on the dash will blink and the “Service 4WD” indicator will be lit because the TCCM never sees a complete 4WD engagement. The ground wire to my front axle actuator was the culprit on my truck.

Why does my dash say service 4 wheel drive?

Service 4 wheel drive in dash indicator comes on and lights go out on the transfer case switch nob. If I turn off the engine and wait for 10 min. then start truck everything is ok. and I can turn nob to whatever location I want and it will shift.

Some customers may comment that the Service 4WD light is on, the 4WD system is inoperative, the 4WD switch indicator lights are blinking or that a grinding noise is heard from the front axle.

How to diagnosis and repair a GM 4WD truck?

Check every function for response: 2HI, Auto4WD, 4HI, 4LO, Neutral. Pull the dashboard apart (it is just held with clips) and pull out the buttons. Disconnect both connectors. Using the DMM, measure the resistance between the innermost pins on both connectors. The resistance should be steady (no changes while the button is pressed).

Is the service 4×4 light on or off?

Service 4X4 light on. Service 4×4 light on dash. 2003 GMC Sierra 1500hd 6.0 4L80E, fully automatic 4×4. Has been working on and off. Usually the light is off after a few days, then the 4L lights up and stays on even though I am driving freeway speeds, transfer case is in 4H but dash says 4L.

What are symptoms of bad transfer case control module?

If the shift is not possible, the selector switch will come on and flash for 30 seconds. Locating the TCCM is not tough. Will BMW End the Production of Manual Cars? Symptoms of a bad TCCM are likely to include flashing a warning message or turning on a warning light on the Driver Information Center (DIC).

When to replace transfer case shift control switch?

You also have to diagnose the connector of the transfer case shift control switch and the ground circuit for ground. If the TCCM fails the self-test but all these circuits turn out fine, you have to replace the TCCM. It is normal to have this message sometimes. It goes away when you shut the vehicle off and then turn it back on.

What does the service 4WD light on a GM Truck mean?

The solid lights on the 4WD buttons are telling you where the transfer case encoder motor thinks it is, and blinks on the mode that it is trying to go to after you push the button. If it fails to move to the new position, it goes back to a solid light on the original position and illuminates the “SERVICE 4WD” light.

What’s the transfer case mode on a GMC 1500?

3. Using the TCSCS, select each transfer case mode/range while monitoring the Rotational Position Sensor parameter and the Incremental Position Sensor parameter on the scan tool, The Rotational Position Sensor parameter and the Incremental Position Sensor parameter should track within 5?degrees of each other.

Can a transfer case be changed in a 4WD truck?

The entire motor can be replaced, or just the less expensive encoder inside can be changed. The transfer case encoder motor moves the transfer case selector automatically. In Auto 4WD, it continually moves the input shaft of the transfer case to vary the amount of torque that goes to the front driveshaft.

Why does my GMC Sierra 1500 say service?

If I turn off the engine and wait for 10 min. then start truck everything is ok. and I can turn nob to whatever location I want and it will shift. But I can drive for 3 miles or hundreds of miles and the indicator will eventually come on again no matter what position the transfer case is in.

What is the GM service 4 wheel drive message?

GM has issued a service bulletin # 09-04-21-001 to address a Service 4 Wheel Drive Message condition on the vehicles listed below. In addition to the Service 4 Wheel Drive Message, you may also have a C0387 or a C0569 trouble code stored.

What is the GM 4 wheel drive Bulletin?

How often does the 4WD light come on on a Silverado?

Question: I have a 2005 Chevrolet Silverado and my SERVICE 4WD light comes on about once a week. When the light is on, the truck won’t engage into 4-wheel drive. When I turn my truck off and start it again, the 4-wheel drive will work until the next time the light comes on.

Why is the odometer on my GM Truck not working?

A common fault on ’99 – ’02 GM trucks was the permanent or intermittent failing of the odometer/gear select LCD. This meant that you were unable to see what gear you were currently in, unable to determine the mileage of the vehicle, and unable to use the trip computer.

How to repair the odometer on a GMC PRND321?

The instrument cluster is held in place by four (4) 7mm hex screws, one in each corner. Remove these. Tilt the instrument cluster forward carefully, and unlatch the large wire harness on the back. The instrument panel can now be removed. Remove the black panel on the back by loosening the clips.

How to repair the odometer on a Chevy Avalanche?

In this Instructable, I will show you how to repair odometer/gear select (PRND321) LCD on your GM truck. In this case, mine is a ’02 Chevrolet Avalanche but this should apply to all GMT 800 series trucks within this age range. A common fault on ’99 – ’02 GM trucks was the permanent or intermittent failing of the odometer/gear select LCD.

How do you repair an odometer on a car?

Lining up the pins of the stepper motors with their corresponding sockets on the PCB, push the board back onto the instrument cluster. Put pressure on the back of where the stepper motors are (see photo). Replace the back plastic cover of the instrument cluster, ensuring all clips are secured.

When does the 4WD warning light go out?

When the ignition key is cycled from OFF-RUN-START and is released back to the RUN position after the vehicle starts, the 4WD warning light should illuminate for 1 to 2 seconds and then go out. If it stays on, or the “Service 4WD System” message is displayed, there is a problem with the 4WD system.

What does ” service 4WD system ” message mean?

Properly diagnosing and repairing any problems found should restore the system to proper operation. The “Service 4WD System” message does not mean it is time for routine maintenance of the 4WD system; rather, it indicates a problem with the 4WD system that should be properly diagnosed and repaired.

Why is my GMC Yukon 4×4 not working?

The truck has never been in accident that I know of so there is no damage to the front axle. The truck has 190k on it, but the engine only has about 60k. The noise it was making last winter sounded like it was coming from the front axle. It sounded like a wheel bearing or a rear end whine but I only heard while in 4wd.

Is there a service 4×4 light on a GMC Sierra?

Service 4×4 Light On: Service 4×4 Light on Dash. 2003 GMC Sierra Service 4X4 light on. Service 4×4 light on dash. 2003 GMC Sierra 1500hd 6.0 4L80E, fully automatic 4×4. Has been working on and off.

Why is the service 4WD light on on my GMC?