Code P1875 and 4wd module 2000 Blazer LT

[birdboyd]

Hello all,

Does anyone have any idea what causes a P1875 code on a 2000 Blazer LT? I understand it is dealing with the electrical side of 4 lo, but why would it cause me sluggish acceleration and loss of RPM's? Also, what does a 4wd module do when it goes out? My 4wd switch currently will either have no lights on or sometimes it will randomly flash all 5 lights at once, but overall the switch is dead. It does not respond to any buttons being pushed. I tried a new switch but it didn't work either.

I have looked at the previous threads, but I can't troubleshoot something that won't even try to go into 4wd. It is completely dead. Anyone with any suggestions?

Thanks in advance

[MT-2500]

Originally Posted by birdboyd

Hello all,

Does anyone have any idea what causes a P1875 code on a 2000 Blazer LT? I understand it is dealing with the electrical side of 4 lo, but why would it cause me sluggish acceleration and loss of RPM's? Also, what does a 4wd module do when it goes out? My 4wd switch currently will either have no lights on or sometimes it will randomly flash all 5 lights at once, but overall the switch is dead. It does not respond to any buttons being pushed. I tried a new switch but it didn't work either.

I have looked at the previous threads, but I can't troubleshoot something that won't even try to go into 4wd. It is completely dead. Anyone with any suggestions?

Thanks in advance

The P1875 code is for 4W low switch circuit.

Do you have a good engine/transmission capable scanner and volt/ohm meter?
If so a good factory repair manual and or A all data sub will led you threw the repair.
http://www.alldata.com/products/diy/index.html

[birdboyd]

Yes, I have both. I do not subscribe as of yet to anything like alldata.

Do you recommend that service? Or would I be better investing in a factory repair manual or both?

I am just trying to see if anyone has heard about anything like this. Mechanics I have talked to are stumped so far, but that was before it started to get worse and not work completly.

Thanks for your time.

[MT-2500]

Originally Posted by birdboyd

Yes, I have both. I do not subscribe as of yet to anything like alldata.

Do you recommend that service? Or would I be better investing in a factory repair manual or both?

I am just trying to see if anyone has heard about anything like this. Mechanics I have talked to are stumped so far, but that was before it started to get worse and not work completly.

Thanks for your time.

Yes the All Data sub is one of the best repair info there is.
24.95 $ US plastic and you can be set up in 15-20 minutes.
But it is only a one year online sub.
Where the factory manual is forever.

When time permits I will send you some info on the code.
Any other codes.
Also make sure all wiring and plugins are good.
The code says circuit. So if you have replaced the witch check wiring real good.

[MT-2500]

Originally Posted by birdboyd

Yes, I have both. I do not subscribe as of yet to anything like alldata.

Do you recommend that service? Or would I be better investing in a factory repair manual or both?

I am just trying to see if anyone has heard about anything like this. Mechanics I have talked to are stumped so far, but that was before it started to get worse and not work completly.

Thanks for your time.

Here is a little info on testing for that code.
http://members.troublecodes.net/crunch/1875xxxx.pdf
Good luck and let us know how it goes.
MT

[birdboyd]

Thanks for the great information MT-2500!! I should be able to work on it early next week and will let you know what I find out.

Thanks again.

[MT-2500]

Originally Posted by birdboyd

Thanks for the great information MT-2500!! I should be able to work on it early next week and will let you know what I find out.

Thanks again.

You are welcome.
And we hope all goes well with it.
Good Luck
MT

[birdboyd]

Update!!!

After running all the tests I could, I found that while there was power going into the 4wd module, it was dead coming out. Bought a new 4wd module and have no problems since. Everything is working.

[Dropdead]

My 2000 Blazer is doing the same thing. I was told I needed a new module. Only thing is, I can't find one anywhere, short of taking it to the dealer. Where were able to locate one? Thanks.

[luckyskips]

I also have a 2000 Blazer LT. It is showing a P1875 code. I took it to a tranny shop and the guy has no idea what is wrong. When I accelerate from a complete stop it acts like I'm driving a stick shift and I'm in to high a gear. I still have 4wd and the lights don't flash (yet). I read one of these and it said the 4wd module. Is that the transfercase control module? Any help would be greatly appreciated. I just bought it 3 weeks ago. Did I make a mistake?

[MT-2500]

Welcome to AF.
To get you started out on the right foot
Always check the date on the post and if it is old let old dogs sleep.

Also bad manners to highjack some bodys else post for you problem.
Please look for and hit the New Thread button and start a new post on your problem.
MT