S202 help

[Elizabetty]

Hi.
I'm still working on making sure the integrity of my wiring is good. I'm not looking to troubleshoot any particular problem right now. I'm trying to learn my diagrams and understand how multiple components grounding through one wire make their way through the harness.

If I'm understanding the wiring diagrams correctly, multiple wires are going to come together at s202 somewhere on the driver side a few inches from the steering wheel breakout and will become one black and white wire which grounds to g102. Can someone tell me more specifically what I am looking for? I don't have much room to move any wiring, let alone start opening the harness unless necessary. If there's a particular point I can look directly at and work from it towards g102 and then backtrack through the wiring under the dash if I have to, that would be great.

 

[mrrsm]

Okay... THIS particular Video is definitive in explaining the import of centrally Grounding ALL of the Major Modules to a Common and Reliable BOLT DOWN Body Ground. Observe this conjunction in close-up views showing Durable, Solid Copper Wires meeting at the Grounding Block fitted with a substantial 10mm Threaded Bolt:

The Electrical State of the PWM (Pulse Width Modulation) technique uses a Single Wire Concept for the Class 2 Network and will vary between "O" Volts and "7" Volts. This demands that ALL of the Modules must have a Common Meet Up Location at the Two Electrical "Combs" (1) found under the Driver's Side Dash Kick Panel and the other (2) being located under the Rear Passenger Seat of the SUV.

Likewise, their Grounds must have a Common Path as well where they can be clustered together, having a single, robust Black Ground Block bolted solidly to the Body or Chassis makes it very convenient so that Techs are not constantly looking at independent Module Grounds all over the Vehicle.

This Video gives a suggested Generic Ground Proofing Maintenance approach and points out where GM has Body Grounds arrayed around various Trucks and SUVs. Naturally, locating these using the information provided in @Realism s Classic Grounds Thread will assist you:

NOTE:

Some will Disagree with using Dielectric Grease in these procedures... But please understand: GALVANIC, DISSIMILAR METAL CORROSION IS WHAT BREAKS DOWN THE CORRECT GROUND AND BONDING STRAP CONNECTIONS. Using Dielectric Grease STOPS Galvanic Corrosion from occurring... and will NOT cause any Loss of having a Good Ground with Current passing properly through those Corrosion and Rust Free Locations:

Electrical Ground locations

While troubleshooting a bad ground I came across some scans of the service manual regarding electrical ground locations for our platform posted on another site. This includes both short and long wheel base, as well as both 4.2L and 5.3L. Credit goes to Wex...

gmtnation.com

And Finally... Here are some SP-201 Ground Block Autopsy Images that will give a better view of what @MAY03LT has tightened down and well describes how to do that in his Video:

See Post #12 via THIS Link:

Electrical Ground locations

While troubleshooting a bad ground I came across some scans of the service manual regarding electrical ground locations for our platform posted on another site. This includes both short and long wheel base, as well as both 4.2L and 5.3L. Credit goes to Wex...

gmtnation.com

 

[Elizabetty]

It's either early in the morning or I'm simply not getting it because I've already handled the splice pack and g201 bolt on the passenger side under the center console dash area. I've also familiarized myself with the diagrams and videos posted. I'm not seeing in any of it where the grounds would come together near the steering wheel breakout before going through the firewall to g102, specifically s202. However when reading online, albeit limited info, I get the impression I should find another splice of some sort for grounds, radio being one.

 

[TJBaker57]

There is the possibility that S202, labeled J202 in some diagrams, is wrapped up inside a harness where it cannot be seen.

I have seen a few such splices though these have generally been just a couple of wires, not so many as S202 seems to have.

I looked through my pictures of the area in question and did not see anything that looked like a large splice item or junction.

 

[Elizabetty]

not so many as S202 seems to have.

That's exactly it. There's a lot. By the time I went through the wiring manual, I had the impression there was going to be something noticeable and obvious. By the time I finished, I posted only two pictures here as an example but I believe there may be more. If you go on a Google deep dive, there will be reference to s202 as a splice but I see other references to it as a solder but I can't imagine that many ground wires would be soldered together to create the single black and white for g102 in the engine compartment.

I believe it was you as well as others TJ that supplied me multiple links to videos and I've also came across some really educational ones myself on how to read wiring diagrams for automotive and everything tells me that that is a connection point of some sort but I feel like I should be able to see it then.

If it is tucked into the harness, I'll have no choice but to look for it there but I was hoping it was something more obvious that I simply wasn't seeing. You know how that goes when something is right in front of your face or when your car keys are in your hand and you can't find your keys LOL

 

[TJBaker57]

Here is a quick example of a single wire spliced to a second wire. This is inside a PCM connector harness where it cannot be seen. I also would think with as many wires as S202 has there would be something visible though.

 

[Elizabetty]

Ty! That visual definitely helps me understand how they may come together.