So for quite awhile I have not had 4x4 in my Blazer. I believe the actuator is bad, however I always could press the 4hi or 4low button and get the transfer case to engage. When I changed my heater core recently I ended up messing up the 4x4 switch, it was apart for whatever reason and I lost the little rubber pieces inside of it so the buttons would not move.

So just recently I grabbed a switch from a local junk yard and put it in. I pressed 4hi and I heard the transfer case engage, but then the lights on the switch went out. I screwed around with it for awhile and finally realized that the switch was wet. (From sitting in the car at the wrecking yard.) I checked all my fuses, and they were fine. So I pulled it apart and put the rubber pieces in my original switch. I plugged it in and all the lights flashed, the 2hi light was now lit. When I press the 4hi or 4lo button however, it will not do anything. If I put it in neutral and press it, both the 4hi and 4lo buttons will light up a few times, but then it will just go back to 2hi. I can not hear the t-case engaging.

I have traced all of my vacuum lines from the transfer case onward and they are all good. (I was going to fix the actuator but the damn t-case won't engage now.) Could it be that my switch is the reason the transfer case will not engage, or is there some secret fuse somewhere that might have been blown by having the wet switch in? I will go buy a new switch if that seems to be the case, but I don't want to replace good parts.

I was all excited to get my 4x4 going again too. -_-


Sorry if this is all jumbled and hard to understand lol.

Thanks for reading.

 

i dont know what coulld be wrong with your 4x4 i know i have the same problem with my 4x4, the lights will work for 2wd and 4hi but no light comes on for 4lo, my 4x4 has worked great until now, the snow season.., now i dont think it is actually engaging anymore

 

Any idea's?

 

search tccm (transfer case control module)
and tcem (transfer case encoder motor)

those should pop a TON of help. tons of tricks and step by step diagnostics for your set up. i take it you're a 3 button (no 4 auto) by your description also?

 

Yes I am. Thanks ABN31B, i'll run a search on those and see what I can come up with.

 

Well time to follow up with how it got fixed.

I was trying to diagnose a draw on my battery, so I was pulling fuses that I figured were unimportant. I pulled out the 4x4 fuse, because it wasn't working anyways. Shortly after pulling it, I realized that for SOME ODD REASON the 4x4 fuse effects the gas gauge and the gear indicator. I then reinstalled it.

Today when I drove to work, I pulled into the job site and realized I was in 4 hi. I was happy just knowing that my switch was working again, but listening I could hear that my transfer case was also working.

On top of THAT, I was going to go check out the front end, assuming the actuator was bad, but NO! The front axle is engaging now too. My 4x4 fixed itself by pulling out and reinserting the fuse. Maybe I reset the transfer case control module by doing so. I'm not completely sure, but I believe it's working.

TIME TO GO FOUR WHEELING. >
(Probably to find out it's NOT working when I get stuck. :P)