The 'service 4 wheel drive system' light has come on and the the 4 wheel drive has never been used. Can I reset a sensor and what is involved in troubleshooting this?

If you can't diagnose any problem with parts involved, you should scan the computer of your car. to get an answer. Might be some problem, bad sensors, a circuit problem or even tha proper computer.

If the wheel tpms sensors work,when you turn on the
ignition switch, the dash light should go off in one second

When you drive 16mph the system is activated & if
tire pressure in the 4 driven wheels are okey, the light
stays off

Other wise you have tire & sensor work to do

Whenever this warning light or any other stays on in the dash it is indicating that the systems control module (or the system sensor in the case of lights like low oil pressure, door open indicators etc.) has detected a fault, it then disables the system (this applies to ABS,TCS, TCM, SRS and BCM faults and others) as long as the light is on. You must now have the dealer hook up a special electronic diagnostic tool and "scan" the system for the fault code that is stored for the problem(s)

Legend of Abbreviations. ABS Antilock brake system.TCS Traction control system, TCM Transmission control module, SRS Supplemental restraint system, BCM Body control module

have you serviced the 4 wheel drive with new fluid? draining and refilling the system with the proper fluid may cure this problem. then reset the life meter for the 4 wheel drive system. hope this helps

Means a sensor has found an issue with the 4 wheel drive system. I suggest you have fluids checked in the transfer case and gearboxes accordingly. If that isnt it rent a code reader at an automotive store to retrieve the code to lock down exactly whats causing the fault.

There is a software updated for this concern if there are no driveabilty problem the dealer needs to undate the 4wd software.

The service 4 wheel drive light comes on because there's a problem. The biggest causes of this I've seen are a software glitch in the final drive control module which the dealer can fix by reprogramming and the other is usually the electric actuator on the front axle housing. The only light that comes on by a timer is the one that says, "perform service" in your overhead console or odometer.

I had this light come on in my 2003 tahoe it ended up to be the transfer case motor (encoder motor) was bad. I got one out of a used part store and the light went off right away.

you have to get the 4 wheel drive system fixed. that is not a maintenance indicator there a a problem and a related DTC when you see that message the code most be checked and repaired it cant be simply reset

If you have push button 4-Wheel Drive, it is recommended that you use it every once in a while, in order to keep gunk, rust, and corrosion to build up on moving parts. The mostly likeley (though not definite) reason would be that you let the 4-wheel drive unused for so long that corrosion has built up on the parts and the actuator that engages the 4-Wheel Drive doesn't have the power to engage it past the corrosion. You'll need to take it in to be cleaned, or to have parts replaced. In the future, every month or so, engage 4-Wheel Drive and drive around in some mud, grass, sand, or any other loose ground for a bit, just to keep the parts moving and clean.

The service Four wheel drive light is to alert the operator the system is not being read properly by the ECU.

If the ECU loses contact with or position of the Transfer case actuator motor the service light will come on. Same thing goes for the front diff actuator.

So it may be a bad switch, sensor, or an actual problem in the 4WD linkage. This is not a Oil Change light that you can ignore a few extra weeks - it indicates a problem that should be taken care of ASAP to avoid costlier problems down the road.
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