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Im Stuck In 4 Lo. Replaced Selector Switch Now What?

firedog

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firedog Enthusiast

firedog

Posted
Posted

I have a 00 1500 4x4. it has the auto 4wd. i went to put it 4wd lo yesterday and the lights flashed then went out on the selector switch. Then the service 4wd came on. after finally flooring it enough in low 1 i was finally able to get out of the mess i was in,because the front tires wouldn't engage. the truck seemed like it was still in low gear when i proceeded to go home. lucky it was only 5 miles. So i did some research and went and got a new selector switch today from the dealer. I came home unhooked the battery cable installed the switch. After i hooked the cable back up i started the truck. the service 4wd light had went off but the selector switch didn't have any lights on. The truck is still stuck in i guess 4lo because the transmission shifts through all the gears fine. Could some one please help me with this.....

O'Three GMC Enthusiast

O'Three GMC

Posted
Posted

Check out the solenoid down on the transfer case. I had the same problem on my 03. The selector switch was a good bet as they do tend to fail. I almost replaced mine as well but had a few miles left on the extended warrany so I took it in. Switch was fine, solenoid was bad. Have not had any probles or Service 4WD messages since. Good luck, winter is on it's way!

Matt_ Senior Enthusiast

Matt_

Posted
Posted

Probably the encoder motor sensor.. (same thing happened to me, stuck in 4lo)

88962315 Is the Sensor and

12384990 Is a new seal

 

 

1) remove front drive shaft

2) remove encoder motor (shift motor) from t-case

3) remove 2-3 screws (ill remember if i look at it) from shift motor cover

4) mark gear locations relative to each other. there's 2 gears and they need to be put back in exactly how they were taken out

5) unplug sensor and remove sensor from larger gear

6) reverse procedure

 

If you have access to a scan tool... dtc C0327 is often indicative of the encoder motor sensor failure.

O'Three GMC Enthusiast

O'Three GMC

Posted
Posted

Good question. As the dealer replaced it, I didn't check it out myself. There are only a few wires running to the x-fer case, but I couldn't say which were for the 4WD solenoid and which were for the Hi/Lo. The shadetree method of testing it would be to just disconnect and put 12V to the thing, but I'm also not sure if those solenoids have some sort of position sensor built in that could fry. If you don't get a better answer to that question this evening, I'll see tomorrow if one of our guys here know the answer to that. We may very well make the thing.

firedog Enthusiast

firedog

Posted
  • Author
Posted
I would start by checking fuses.

 

 

And after doing some reading on here. i now know that theres a fuse for the "automatic transfercase" and guess what.......... it was blown! so after putting in a new one. im good to go. So i will gladly accept the dumbass of the year award. :eek:

sillyazz Enthusiast

sillyazz

Posted
Posted
I would start by checking fuses.

 

 

And after doing some reading on here. i now know that theres a fuse for the "automatic transfercase" and guess what.......... it was blown! so after putting in a new one. im good to go. So i will gladly accept the dumbass of the year award. :eek:

 

Glad you got it fixed.

Ran into the same thing at work thats why I said check fuses first . Sometimes people forget to check the basics before throwing a bunch of time and money into it.

sillyazz Enthusiast

sillyazz

Posted
Posted
I would start by checking fuses.

 

 

And after doing some reading on here. i now know that theres a fuse for the "automatic transfercase" and guess what.......... it was blown! so after putting in a new one. im good to go. So i will gladly accept the dumbass of the year award. :eek:

 

Glad you got it fixed.

Ran into the same thing at work except it was on an S-10 Blazer ,thats why I said check fuses first . Sometimes people forget to check the basics before throwing a bunch of time and money into it.

 

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