I was installing a new radio in my 1998 tahoe. I diconnect the auto 4x4 button and disconnect the battery of the truck. I whet to put it all back together and forgot to plug the auto 4x4 button in. Now the tran service light is on. I plugged the 4x4 auto button back in and the trans serivce light will no go off and the 2 hi/4auto/4hi/4low does not light up or do anything. I checked the fuse and that is ok. Do I need to reset the auto 4x4 button some how? Any help would be great. thanks

There is 2 fuses for it.
T case fuse 2 and 4WD fuse 24.
Check both for 12 volt power on both sides with a test light?
Can you get it to or hear it shift by pressing 4WL or 4WH button?
MT

I am sorry.. I forgot to state. The #2 fuse was blown and when it was the service light is off. I replace the fuse and the service light come on. There is no clicking when I hit the button. No change. Under the hood by the fuse box there is a orange wire that I took off when I also connected the elec brakes back up. Label aux 1 and 2. there is 12volts going there. I will check the fuses with a test light to see if there is power there. Right now I disconnected the battery over night thinking it might reset the ecm/trans computer memory? Or does it need to be disconnected longer? #24 fuse was not blown. I am going to get a scan tool this weekend. Is there somewhere that will tell me what/if a scan number comes up what it means? Book/internet? thanks for the help so far.

If checking all power feeds and the battery disconnect does not help it is time for the transmission/transfer case capable scanner.
On a good capable scanner there should be some shift and other test you can run on it.
If it shows any codes post back the code no.
MT

Thanks for the help so far. I will check this weekend

both fuses have power. I went to auto zone and rented a actron autoscanner cp9136l obdII but it does not pull trans codes. Is there a place I can rent one that does? Any help would be great. thanks again

both fuses have power. I went to auto zone and rented a actron autoscanner cp9136l obdII but it does not pull trans codes. Is there a place I can rent one that does? Any help would be great. thanks again


I do not know of any. But call some other local auto places.
The transmission/transfer case and engine capable scanners are the high end high dollar ones.
2 to 10K dollars.
For a one time check or test out on it a good repir shop with one would be you best bet.
Most will test one out with a set or about a hr. diagnostic fee
Dealers can check it but most usually more money.
Good Luck.
MT

Hey I was told my 4x4 computer of the trans case went. Dealer told me it would be 340.00. Plus another 150 to put it in. WHere is this computer at? Is it something I can install? Please let me know. thanks

Hey I was told my 4x4 computer of the trans case went. Dealer told me it would be 340.00. Plus another 150 to put it in. WHere is this computer at? Is it something I can install? Please let me know. thanks

Behind left side of dash mounted to steering column bracket.
What was the codes or what he find on it?
MT

I was told that codes u1026,u1041,u0016,c0308,c0895 the tech cleared all codes and one came back... I forgot to ask which one but i was told getting bad volts from the 4x4 module. needs to be replaced. Does that sound right? Also is there a part number i need to look for? Is this a dealer only part?

Depending on the code that came back and the voltage readings.
But I would make sure it is getting good full power to it.
The codes point to a voltage problem.

As far as I know it is a dealer part only.
Your dealer can run your vin for the part no. and or for any changes or updates on the part and part no.
Sometimes a dealer will give you a break on the list price.
Good Luck
MT