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Too Many Grounds?

Badaxe

Badaxe

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OK so the PT Wiring Kit came in and it seems simple enough. However it seem that the PO went a little over kill making sure things were grounded. Granted he was running three TVs, all the sound to support them, an alarm from 1994 with more relays than two of our trucks put together, and a high output alternator that has since died. But this is what you see under the hood.

First is photos and then a simple diagram, power wire to alt and starter are backed with a second wire with fusible link. Like I said lots of redundancy.

DSC01330.JPGDSC01331.JPGDSC01332.JPGDSC01333.JPGDSC01334.JPGDSC01335.JPGDSC01336.JPGDSC01337.jpg
Battery System.jpg
 
It's been drilled into everybody's heads over and over that you can NEVER have too many grounds on a 6.5. I'd believe the mantra myself... ;)
 
Yeah,, like Crank said,,, Stop Fu#%en with stuff!!!!

IMO I'd leave them too,, at least he did a good job on them,,, We've all here seen worse!
 
That's the problem......It is broke. Crank, crank, crank, crank, no start. Part of the reason I'm putting in the PT Wire Kit is my "waiting for a tow" post. So y'all are saying that all the spaghetti in the diagram makes sense. It does to me too, but if it can be cleaned up in the process might as well. Buddy gave me some good leads to follow on Wednesday, but if no start then start the bidding.
 
Between PT's kit, various small parts, the new batteries last week, and the cost of a rental car to get to places I've had to be.....if this doesn't work I'm fubar, to put it simply. You can do the math, and financially for me it does correlate to food on the table. If I don't get it running then the bank can have it or it ends up a non-running trade-in for a Civic. Neither is what I want, I planned on many weekend camping trips with my three small boys this summer, and as someone who grew up playin' in the dirt a ricer or minivan won't cut it.
 
The stock alternator wires are undersized - like a lot of other stock electrical on these trucks. Adding and additional wire to the other battery is standard on my vehicles
 
Sorry about venting guys. A lack of time and no obvious problem/solution has made me a little stressed. With God's grace it will fire right up tomorrow when I get it rebuilt. It should be something simple considering it didn't die, it just wouldn't restart. Alarm has never been a problem(only way to get into truck) but lots of pieces and parts to act up.
 
With the electronics, the sensors need good grounds otherwise you get noisy readings.

You have 3 items that need ground, Engine, Frame, Cab.

Since the most current is needed by the starter, good heavy grounds between the engine block and the battery are needed. A back up ground is done to the fender for the cab. There should be the ground straps from the engine block and frame, and frame to the cab.


All the engine sensors and actuators ground directly to the engine block, (back passenger side of the manifold.) There are about 4 or 5 of these grounds. Any one of the these can stop the engine if they break.


Tying things off were they don't belong can cause ground loops and weird behaviors. (ground loops are usually seen with fire alarm issues)


Verify your grounds at the point of use. Most of the GM grounds are black wires. Pull a connector and check resistance from the ground pin to the battery ground cable. On these trucks, ground is important. just as important as having voltage.


Good luck, chasing electrical problems can drive you nuts.
Just remember its not magic, think plumbing - voltage is pressure, current is flow, wires are pipes, and bad connections are like a leak, or blockage.
 
Good luck, chasing electrical problems can drive you nuts.
Just remember its not magic, think plumbing - voltage is pressure, current is flow, wires are pipes, and bad connections are like a leak, or blockage.
Click to expand...

Thats a good analogy John......I'm gonna remember that one!:thumbsup:
 
jmiller said:
With the electronics, the sensors need good grounds otherwise you get noisy readings.

You have 3 items that need ground, Engine, Frame, Cab.

Since the most current is needed by the starter, good heavy grounds between the engine block and the battery are needed. A back up ground is done to the fender for the cab. There should be the ground straps from the engine block and frame, and frame to the cab.


All the engine sensors and actuators ground directly to the engine block, (back passenger side of the manifold.) There are about 4 or 5 of these grounds. Any one of the these can stop the engine if they break.


Tying things off were they don't belong can cause ground loops and weird behaviors. (ground loops are usually seen with fire alarm issues)


Verify your grounds at the point of use. Most of the GM grounds are black wires. Pull a connector and check resistance from the ground pin to the battery ground cable. On these trucks, ground is important. just as important as having voltage.


Good luck, chasing electrical problems can drive you nuts.
Just remember its not magic, think plumbing - voltage is pressure, current is flow, wires are pipes, and bad connections are like a leak, or blockage.
Click to expand...

That's a damn fine post!

Couldn't have said it better myself :)
 
I have had crazy electrical issues caused by the bulkhead connector. I have fixed a couple of bulkhead connector issues for others that the shops had given up on. Just putting that out for thought.
 
Lots of good advice, thanks y'all. Question in regards to alternator photo and last two pics, the diagram is a little off.......

1) White wire at alternator ground goes to screw in fender, redundant but will rebuild, OK no question there.
2) Drivers side + cable has three wires; Large BLACK cable comes from the passenger side as it should, GREEN wire has fusible link built in and goes directly to alternator, and RED goes to fuse on fender and connects to a Black wire that meets up with the GREEN fusible at alternator

So as far as the second issue goes this is my thought, Eliminate the GREEN and take New PT RED to alternator as designed, and then come off battery to fender fuse and eliminate black fuse to alternator wire.

Also found that the wire to alarm hood pin had come loose, so we'll see what effect that had.
 
The answer to the thread title question is a qualified yes. To recap. Grounds need to be in a star pattern electrically speaking. All returning to a central location in the case of a vehicle that would be the battery negative. Ground loops are formed when the star rule is not followed. This was not such a big deal in the past but with all of the sensors on cars/trucks these days it can be. I have chased problems in industrial situations that were tough nuts to crack and it turned out grounds were added or moved and caused a loop.
 
L98, what do you suggest based on my diagram and the clarifications just made?
 
Badaxe said:
L98, what do you suggest based on my diagram and the clarifications just made?
Click to expand...
I didn't see any clear case of ground loops in the drawing. I am more an advocate of beefing up the factory grounds. Larger wire, star washers, copper lugs, copper anti seize, and so on.
 
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