Recently bought an '03 Yuk XL - Service 4WD

[03yukXL]

Hi guys,

I recently picked up an 03 in really good shape. Has some issues and I have enjoyed putting it right. One thing that crept up the other day is the dreaded "service 4wd" message in the cluster readout..

Seems to come on intermittently, but then after the truck is shut off and left for a while, it may or may not be on the next time. When it is on, I can shift through all of the 4wd options and it appears the 4wd is working correctly (i can hear the front prop shaft working). Any thoughts on which of the 4 or 5 components could be the issue? I suppose I could jack it up next time it's doing this and see if the front actuator has engaged the front axle?

 

[Scottydoggs]

you'll need to scan it for codes. the code leads you right to the issue.

 

[Fless]

You need a somewhat advanced scanner, not just an OBDII scanner, to check the 4x4 for codes and operation. A Tech 2 is the factory tool that can do that easily; there's a list here of Tech 2 owners who are willing to help if needed. Tell us what part of the country you're in.

@George B is this the latest?

Tech2 Owners

docs.google.com

 

[03yukXL]

I'm in PA, just north of philly. Wonder if somebody could read the code? That would be really generous. May owe such a person a couple beers!

 

[George B]

Wisconsin for me so no help.
You need to know the code and do some diagnosis. Could be any number of things and the parts canon approach can get expensive.

 

[Sam Harris]

You need a somewhat advanced scanner, not just an OBDII scanner, to check the 4x4 for codes and operation. A Tech 2 is the factory tool that can do that easily; there's a list here of Tech 2 owners who are willing to help if needed. Tell us what part of the country you're in.

@George B is this the latest?

Tech2 Owners

docs.google.com

Hey Steve, you can add me to that list.

 

[Sam Harris]

My gut says it’s the encoder ring. (P/N: 88962315)
That is probably because it’s a fairly cheap, easy to replace part I had intermittent issues like you’ve described, which eventually got a little worse. The T-case was never actually in the wrong gear, but once I started her up and saw it showing 4-lo, I decided I had enough with the DIC message, and inability to actually change to 4-hi in case I really did need it. Before that, it was generally cleared with a stop / power off / start sequence.
I did, however confirm the code, prior to doing any work, or buying the part. That is a necessity, unless you have a lot of extra $$ around. In which case, I really want to start a 6.0 build. Can you please sponsor me?

 

[Scottydoggs]

I'm in PA, just north of philly. Wonder if somebody could read the code? That would be really generous. May owe such a person a couple beers!

this free app https://play.google.com/store/apps/....obd2.chevroletsys.chevroletsysscanfree&hl=en and a droid device and a obd2 bluetooth reader can read all your codes. they list using the elm327 bluetooth. that ones now junk due to china clones flooding the market. use the bafx brand. its like 20 bucks.

 

[rockola1971]

Typically its the encoder ring (AKA Commutator or Shift motor position indicator). They get a dead/worn/dirty spot on them and the 4WD module gets lost and does not know what position(mode) the Tcase is in. Next time you are running without the message showing, shift into 4wd then 2wd then Auto4wd (if you have it) and exercise the Tcase. This typically cleans the encoder up if its dirty.

 

[03yukXL]

this free app https://play.google.com/store/apps/....obd2.chevroletsys.chevroletsysscanfree&hl=en and a droid device and a obd2 bluetooth reader can read all your codes. they list using the elm327 bluetooth. that ones now junk due to china clones flooding the market. use the bafx brand. its like 20 bucks.

I took your advice and picked up the BAF Elm327 reader and downloaded the app. It doesn't seem to give any transfer case codes even with the Service 4WD message on. Any thoughts on how to get the device to pick up the code? Would you mind walking me through it?

Thanks for your help-