So what is this then?

[DrWin]

Hi guys,

I'm having a look at the weatherstripping, and came across this by the front door / trunk area. What is this good for?
65804

There's one on the passenger side too, but that one has been torn in two.

[Michael]

Not factory. There is a small grounding wire in the fuel filler area I believe for static discharge but I have no idea what that could be or why I wouldn't just rip it off and forget about it.

It might be PO mod to help the windshield antenna assuming it has one.

[dn010]

Not factory.

I do not believe that is accurate. My car also has these ground straps on on every single panel, even a ground running under the windshield/urethane on the lower passenger side. For one reason or another, they wanted to make sure all the fenders were grounded.

[Helirich]

I do not believe that is accurate. My car also has these ground straps on on every single panel, even a ground running under the windshield/urethane on the lower passenger side.

Mine has the grounds all over too.

[MrChocky]

Hi guys,

I'm having a look at the weatherstripping, and came across this by the front door / trunk area. What is this good for?
65804

There's one on the passenger side too, but that one has been torn in two.

As others have stated, grounding straps for the fenders. Mine are bust too; probably not a big deal unless you want to replace.

[Ron]

The straps are factory. They prevent electromagnetic interference from getting to and escaping from the electrical parts of the vehicle. So why when the engine is in the back? They want all of the panels to have the same potential...
Check out Faraday Cage (https://en.wikipedia.org/wiki/Faraday_cage).

(Michael, FWIW, antennas work best when mounted as far away from grounded metal masses as possible, especially for transmitting.)

[Michael]

My mistake, I thought it was just hanging there in plain view. Never saw those before but the number of DeLoreans I have personally seen is under 20.

AFAIK, none of my panels are grounded. Maybe that's why my radio reception sucks?

[David T]

Because all of the panels are bolted to a fiberglass underbody and are not mechanically connected to each other, they are bonded together by uninsulated braided cables. They are bonded for a couple of reasons. For the radio, for static electric and to get any stray currents grounded back to the battery. Most of them are probably rotten and/or broken but they should be maintained in good repair for safety purposes. There are some things that are electrically powered that attach to the panels like the power antennae and marker lights.

[Michael]

Where is the main ground(s) these wires eventually connect to? Do they just daisy chain together from a single ground?

[dn010]

Where is the main ground(s) these wires eventually connect to?

The panels seem to be a chain and I believe they are grounded to the rest of the system under the dash via the wire that is glued under the windshield, passenger side. I never would have known this wire even existed until I pulled my windshield for replacement.

FWIW, these panels seems to be grounded regardless of having these straps or not. I have many of these either broken or missing now and I've still caused sparks by accidentally shorting something on a panel.

Edit:

Here is the wire. I am not at home to look at my car in order to really refresh my recollection but if my memory is fine, the wire continues from the windshield opening, under the cowl and connects to the passenger side front fender. Someone please feel free to correct me if I am mistaken.

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[Ron]

Where is the main ground(s) these wires eventually connect to? Do they just daisy chain together from a single ground?Main bulkhead bolt => Blower Motor => Dashboard Bolt => Body Panels. (With branches elsewhere along the way).

They will have little/nothing to do with your sucky reception if WRT being "weak"...more for interference from other sources, "static" and/or electromagnetic interference.
Maybe TMI, but without the grounds, if you were to drive under low electricity transmission lines, your radio would cut out (some do anyways) and your engine may die (screws up the electronics...).

[Michael]

Maybe TMI, but without the grounds, if you were to drive under low electricity transmission lines, your radio would cut out (some do anyways) and your engine may die (screws up the electronics).

That's heavy!

[Ron]

LOL


P.S. I should have said some engines would die (due to poor component shielding). I doubt it would affect a D.

[DMC-81]

I saw these grounding straps when I refurbished my car, especially the windshield surround and the front fender area.

http://dmctalk.org/attachment.php?attachmentid=46803&d=1477098898

A couple of them were frayed/broken, so I replaced the tinned, copper braid.

http://dmctalk.org/attachment.php?attachmentid=46392&d=1475148955

[DrWin]

Seems like I should keep / repair them then! :)

[JohnnyK]

Main bulkhead bolt => Blower Motor => Dashboard Bolt => Body Panels. (With branches elsewhere along the way).



Somewhat off topic Ron, but a question I was wondering last week while pinning out an old harness. There are many grounds with ring terminals coming out of the harness (especially around the center console area). Are those joined to the main bulkhead ground (which would make them unnecessary), or are they just 'loose' grounds, that need to attach to the grounds you mentioned?

(Actually, I just multimetered it out, and it looks like the only ground/ring terminal that isn't connected to the main bulkhead ground is the one that should come out near the blower motor. So how does one ground the blower motor ground wire?)

Thanks!

[Rich]

...So how does one ground the blower motor ground wire?

The factory blower motor ground wire runs from the main bulkhead ground forward to the one of the spades on the double-male spade connector that's attached to the blower motor flange by one of the flange mount screws. There are ground wires from other elements connected the other spade on that dual connector. In other words, the grounds for those other elements terminate at that common dual-spade connector to be grounded in turn to the bulkhead ground, along with the fan motor.

That's the part of the circuit Ron describes in the first two words of his written ground schematic. (Main bulkhead bolt => Blower Motor => Dashboard Bolt => Body Panels)

This schematic (http://dmctalk.org/attachment.php?attachmentid=4436&d=1314234217) might help. Taken from one of several posts in this thread (http://dmctalk.org/showthread.php?1371-DeLorean-Ground-Schematic/page3&highlight=grounds+diagram)

[JohnnyK]

Thanks Rich. Yes I see that spade terminal now, I guess what I am looking at is not the blower ground. This is 2 ring terminals (large and small I believe) about 1.5 feet back from the blower connections, but after what I think are the glove box wires (car isn't built yet. Going by a schematic, they are the glovebox lamp wires).
Unfortunately that ground schematic seems to locate the bundles of grounds that are heatshrinked together, but not the individual ring terminals (or is missing a fair bit of them). IE, the terminals I mentioned near the center console, that still show continuity with the rear bulbkhead ground (So why are they there? Seems strange!)

[Ron]

Somewhat off topic Ron, but a question I was wondering last week while pinning out an old harness. There are many grounds with ring terminals coming out of the harness (especially around the center console area). Are those joined to the main bulkhead ground (which would make them unnecessary), or are they just 'loose' grounds, that need to attach to the grounds you mentioned?

(Actually, I just multimetered it out, and it looks like the only ground/ring terminal that isn't connected to the main bulkhead ground is the one that should come out near the blower motor. So how does one ground the blower motor ground wire?)

Thanks!

For prosperity:
65816

[Drive Stainless]

For prosperity:
65816

Or posterity.

Copyright 2011 Bill Robertson.


Sent from my iPhone using Tapatalk

[Ron]

Or posterity.

Copyright 2011 Bill Robertson.Yeah that too. :biggrin: [Where was Rich when I needed him?!]
Yes, that's Bill's work, exactly as he posted it...

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Me thinks spring fever is in the air...