4wd System Operation & Help Thread

this is true not meant for permanent. But looking at the loads on that circuit the canister pump only runs with the truck off and the rest only operate while switching 4wd in and out. Not much load that I see to cause harm.

 

I'm also really curious where exactly that ground goes bad because it seems to be a relatively common issue and I haven't gotten that far with anyone to find the exact spot yet. If I knew exactly where and how it fails it would give another data point to this whole thread.

 

yeah I’m not sure. But if it was me I’d take that grounding point and get rid of it and solder a big fat 12 gauge cable to the existing ground cables and then run it straight to the battery.

 

The ground point itself isn't the problem but with grounds like those in a corrosive environment like in the salt belt (not sure if he lives in an area like that or not) the wires tend to corrode internally and will look intact but in fact be corroded in two. I've also seen many times where the individual wires will break off from vibration (99-06 GM trucks were notorious for this).

On a side note I'm onto some new tests to help diagnose the P035x coil circuit codes that also seem to be relatively common.

 

the real issue is the use of dissimilar metals because I believe that point is on the cylinder head or block area, that will accelerate it. I would cut back the ground harness to good fresh copper then run it directly to the battery or chassis.

 

I’m in central Ohio, the corrosion is awful. I just took EE off and sanded everything down. An aircraft mechanic checked EE and said it was a good ground but did mention that doesn’t mean the wires are intact. When back probing 18 should I have the key on? Do I set the multimeter to vdc and touch one probe to 18 and the other to a ground? What should I see?

 

I can get a cheap scan tool on Amazon for $20. Might be the ticket.

 

yes. Should be almost 0VDC. If you are reading a potential that means the voltage is not getting grounded properly from the EE ground point.

 

I’m reading zero volts with the key on.

 

Ok what about on pins 7 and 19 of the same connector?

 

Pin 7 is bouncing around .01 and 19 is empty. Key on

 

19 should be populated, are you sure your on the right location?
PA pins 18 and 19 should be the 2 White/Black wires on the top connector where my finger is.

 

Nope, I didn’t realize the picture was upside down. I’ll be back.

 

Pin 18 is 12.5
pin 19 is 12.5
Pin 7 is 12.5

 

Nice, that confirms the wire is broken somewhere between Pin 18 and ground point EE.
You have 2 options, you can continue to look where the wire is broken or you can cut the wire at Pin 18 splice a wire to it and run it from Pin 18 to an interior ground stud.

 

That’s great news! I’ll give it a try. Thank you very much!

 

Let us know how it goes, I'm still curious where exactly that wire is broken but I understand if you don't want to chase it anymore.

 

It works!!!!!!!!!!! DM me your PayPal. I’ll buy you your favorite 6 pack. Cruise control too!

 

I really don’t want to open up the wiring harness. It will probably cause more damage than good. I willing to bet when they did the frame swap something didn’t get put back where it was suppose to. But that was 5 years ago.

 

Nah I'm good, I'll definitely remember this for the future for quicker testing.

Question though in the picture it looks like you are on pin 19, it's hard to tell.

The pins are numbered from the top.

22
21
19
18
17
16
15
14
13
12