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Service 4wd and no lights on selector switch

(1999 Chevrolet Silverado 1500)
in Green Bay, WI on August 05, 2014
the lights on the transfer case selector switch in the dash no longer comes on. it does flash when turning the key to start the truck, but it remains in two wheel drive. Ive changed the selector switch, but that did not work. The codes say transfer case shift motor, but could it be a bad ground connection giving me this code as well?
Displaying 3 answers & 11 comments
Popular Answer
on December 03, 2014
I have the same exact problem. I have replaced the selector switch,encoder motor(which there was a code for when scanned)and cleaned the ground connections and still no luck. Have you figured yours outyet? I'm beginning to think I have a bad module
on January 07, 2015
2006 silverado 1500. 4x4 would not engage on mine. I would receive service 4wd message on dash and 4wd switch would change light locations randomly. Changed swich and it did not fix the problem. Changed the encoder ring and the problem was fixed.
on March 01, 2015
I have the same exact problem, I actually changed the transfer cases motor, and when I tried pushing the button, still no lights on the selector switch, and the dash now says service 4WD and stays on kike that, although the truck is on 2WD and drives fine. I'm taking it to the dealer and get a diagnostic
on March 02, 2015
You need a new transfer case control module. I had the same problem and a new TCCM solved it.
on March 06, 2015
I got a new one from autozone, dorman product part# 599-114, still no luck, is there a special way of connecting the harnesses back, do I disconnect the battery first? Running out of option, and loosing hope
on March 10, 2015
you might not have power to the module.check the fuse for the transfer case on the left side of the dash. Also check the ground wires bolted to the frame right below the front of the drivers door.
on March 10, 2015
I already scraped off the ground wire and the frame where it bolts on, I checked all the fuses actually in the side, is there another fuse somewhere?
on March 11, 2015
No there no other fuse. Check the smaller 4 wire connecter at the module. Make sure it had power and ground. I believe it's a red and black wire. Check it with key on
on March 11, 2015
I'll check that next day off, BTW, I had the dealer diagnose it and they said they can't get any code at all from the "service 4WD" message
on March 11, 2015
They mayhave not had the right scan tool, a lot of your scan tools will not go into the BCM codes. I would assume at the dealer they would havethe correct scanner but you never know.
if they did use the right scanner and truly did not get any codes then it sounds like the module is not working at all.
on March 13, 2015
There is a reflash for the TCCM costs about $85.00 at GM dealer. Do not buy more parts until you have it reflashed
on March 13, 2015
They call it re-program here and they charge $135, but, guess what, I drove it to ATV park today, rode my ATV for a few hours and then when when I got back, the light from the switch came on, and the light was on 4LO, so I parked, put it on neutral, put it back in 2HI, then it seems to be working normal now, I hope it stays fixed this time. I'll keep you all updated, I'll keep driving the truck for now for observation.
on March 14, 2015
When I replaced the Tccm(which I bought used) the s system worked for a few times, then it stopped working. Then a few days later it started working again. I suspect it has something to do with the flashing as written in the previous post. Anyways glad it's working for you.
on March 14, 2015
If it stops working again, I will take it in to get reflashed, thanks for the advices
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