Big Three Replace Factory Grounds?

[iamdub]

Thank you for that explanation “iamdub” (sorry I misspelled your name earlier ), I will attack these 5 areas first, then eliminate the localized issues if still there.

The one I’m worried about is Service 4WD (have heard of people getting stuck in 4WH or 4WL). I’ve cleaned the frame mount grounds. I’ve found the small 4 pin connection on inner drivers fender, cleaned the 4 pin sockets, added dielectric grease and grounded the black negative wire to the firewall ground.

This was good for a week, then display came back. It has to be electrical - when the dash switch for AWD, 2WD, 4WH and 4WL are lite and functional, I can switch back and forth - no problemo!

After the above advice I should check transfer case control module and transfer case motor - plug-in sockets and ground wires.

Your thoughts?

Honestly, I'm not very well-versed on the 4WD systems. The only 4WD vehicle I've ever owned was an XJ and I've never worked on a GM 4WD system other than replacing axles and hubs.

From browsing this forum over the years, I know the module (Might be properly known as "encoder" or "encoder motor") is a somewhat common failure point.

 

[George B]

Thank you for that explanation “iamdub” (sorry I misspelled your name earlier ), I will attack these 5 areas first, then eliminate the localized issues if still there.

The one I’m worried about is Service 4WD (have heard of people getting stuck in 4WH or 4WL). I’ve cleaned the frame mount grounds. I’ve found the small 4 pin connection on inner drivers fender, cleaned the 4 pin sockets, added dielectric grease and grounded the black negative wire to the firewall ground.

This was good for a week, then display came back. It has to be electrical - when the dash switch for AWD, 2WD, 4WH and 4WL are lite and functional, I can switch back and forth - no problemo!

After the above advice I should check transfer case control module and transfer case motor - plug-in sockets and ground wires.

Your thoughts?

You really need to know what trouble codes it is storing for the issue before you can go much further. You were right to start with the grounds but now you need to know what component or circuit is malfunctioning. You should start another thread about it.

 

[Rolexus]

Thanks George, I was trying to deal with some of the more obvious sources of the problem in the simplest ways first, prior to taking the truck into a shop for a scan

 

[Rolexus]

Honestly, I'm not very well-versed on the 4WD systems. The only 4WD vehicle I've ever owned was an XJ and I've never worked on a GM 4WD system other than replacing axles and hubs.

From browsing this forum over the years, I know the module (Might be properly known as "encoder" or "encoder motor") is a somewhat common failure point.

Thanks iamdub! Appreciate your thoughts anyway! Cheers, D

 

[George B]

Thanks George, I was trying to deal with some of the more obvious sources of the problem in the simplest ways first, prior to taking the truck into a shop for a scan

If you plan to keep the truck a while invest in a Tech2 and set yourself free from the shop charges for diagnostics.

 

[Joseph Garcia]

If you plan to keep the truck a while invest in a Tech2 and set yourself free from the shop charges for diagnostics.

As @George B stated, the Tech 2 is an invaluable diagnostic and programming tool. I guarantee that you will recover the cost of the Tech 2 (~$350) the first time that you use it to diagnose and resolve an issue. I figure that my Tech 2, which I use sparingly, has saved me well over $1500 so far, in diagnostic work that would have been performed by others.

 

[Rolexus]

As @George B stated, the Tech 2 is an invaluable diagnostic and programming tool. I guarantee that you will recover the cost of the Tech 2 (~$350) the first time that you use it to diagnose and resolve an issue. I figure that my Tech 2, which I use sparingly, has saved me well over $1500 so far, in diagnostic work that would have been performed by others.

Thanks Joseph, I have had the Tahoe for 3+ yrs now and absolutely love it - except when something goes wrong...lol

I will look into a Tech2, but being from Canada, the $350 you paid will be closer to $450 plus tax in our $CDN. But as you say, it’ll pay for itself in short order. Cheers, D

 

[Rolexus]

If you plan to keep the truck a while invest in a Tech2 and set yourself free from the shop charges for diagnostics.

Yes, I relied to Joseph (below), so this is definitely on the radar in the near future. The shop charges I incur up here (Surrey, BC, Canada) are ~150/hr., although this place is GOOD, especially for stuff I can’t do.

Question: Is the Tech2 you mentioned the brand or the generation of scanner? If generation, do you have a mnfr. brand I can get from you to reference? Thanks!

 

[Joseph Garcia]

Thanks Joseph, I have had the Tahoe for 3+ yrs now and absolutely love it - except when something goes wrong...lol

I will look into a Tech2, but being from Canada, the $350 you paid will be closer to $450 plus tax in our $CDN. But as you say, it’ll pay for itself in short order. Cheers, D

Here is where I purchased my Tech 2, and the current price is $275 US. It is a Chinese knockoff, but virtually all of them are today, but they still work as designed. I received my Tech 2 about 3 weeks after I ordered it.

https://www.aliexpress.com/item/1005001627663288.html?spm=a2g0o.productlist.0.0.4c617ff7k5FQYO&algo_pvid=e478db80-28d5-4ee3-b777-034521d96d0c&algo_exp_id=e478db80-28d5-4ee3-b777-034521d96d0c-28&pdp_ext_f={"sku_id":"12000016877986130"}

 

[Rolexus]

Here is where I purchased my Tech 2, and the current price is $275 US. It is a Chinese knockoff, but virtually all of them are today, but they still work as designed. I received my Tech 2 about 3 weeks after I ordered it.

https://www.aliexpress.com/item/1005001627663288.html?spm=a2g0o.productlist.0.0.4c617ff7k5FQYO&algo_pvid=e478db80-28d5-4ee3-b777-034521d96d0c&algo_exp_id=e478db80-28d5-4ee3-b777-034521d96d0c-28&pdp_ext_f={"sku_id":"12000016877986130"}

Thanks Joseph! Cheers, Dwayne