Landseer

Another source of pictures of ground points, and diagrams, specific to the early-bodied is on the CDs
Electrical 928 Training document.

Wastib's car is in-between the early cars and the S4 diagram shown, a hybrid

Speedtoys

Good thread..Im replacing both of my main ground straps..engine and battery, with welding cable.

Very very fine, made for high current. You want total surface area in a cable..not just "thick".


Edit: And it appears that the Internet is in two camps. Team Jacob and Team Edward on this one..and I could be very wrong...ya..probly am.

txhokie4life

I'm not a cable expert -- but it is my understanding that
high frequency AC skin effect comes into play
and the skin depth means that the current
runs very shallow in a wire.

Therefore at DC being essentially 0 hz, it has maximum skin depth
and will use the entire cross section of a wire.

for a given cable thickness, a solid core would be better for DC than
stranded wire.

there maybe some other effects I am not aware of, but
solid core seems like it would be best for DC conductance
all other things being equal.

Mike

Mattman928

I have a 1990 GT. In the attached photos you can see the two locations of those ground points. In the photo, I have removed the air filter housing as well as the MAF. The two gound points are on top of the bell housing, on the bolts that hold the throttle cable pully bracket to the bell housing.

Jadz928

Nice pic of those 2 elusive GPs, Matt! (however should be rotated 90 degrees )

These two wires ground the LH and EZ brains via the wire harness. Car will not run with these disconnected.

White Lightnin'

This would be a really great addition to the FAQ thread at the top of the 928 forum list... a diagram with 'roll mouse over' capabilities and with the differences seen in the different model years!

Landseer

Yeah, gotta shake head everytime somebody says "see the FAQ" and doesn't realize the answer isn't there. Seems to happen twice a month on grounds.

Time for a FAQ / newbie re-write.

SanDiego928

Great thread. Learned more. I am smarter now.

uncre8tv

Resurrecting one of the many ground threads to ask:

In my '89 S4 there isn't any terminal in MPIX, just the throttle cable cam bracket, and the cable clamp which doesn't look like it carries any current. Can someone confirm that is correct for my MY?
The MPVIII has two terminals as pictured above.

thanks in advance all.

Mrmerlin

someone has miswired the connections one wire goes to each bolt that holds the wheel bracket to the block.

Alan

BTW - cleaning - clean the minimum you need to get to a shiny clean surface. Don't use a wire brush if you don't need to. You want a completely flat clean surface with the original plating. If you use a drill/dremmel - use a brass brush. once clean (can use alcohol to ensure oil/grease free) - cover with a contact enhancer: Stabilant/ DeoxIt Gold etc - just dab on with a Q-Tip (clean the ring terminals also - same way). Bolt together - then spray with a contact protectant spray (battery terminal protectant).

Dielectrc grease doesn't conduct - if you use it put it on after you have made the connection.. The sprays are typically just easier to use to get good coverage.

Alan

uncre8tv

Actually found a new, unused drywall sanding sponge laying around the garage from an old home project. It does a nice job of getting a shiny surface without any visible abrading of the surface. Best for the plating? probably not. But gentle enough to make me feel good about it.

http://www.homerepairtutor.com/wp-co...t-Adhesive.png

FreedP

.
Apply with Q tip between connection surfaces.
.

eijun

Interesting, so the grounding points affect the car electrical transfer then.

If I was cleaning the grounding points I think I will end up putting in newer thicker wires (and might end up replacing all wires in the car while I am at it)

Bilal928S4

I was just on the phone with the technical service department at DeOxIt.
They said that their D5 product is for cleaning the contaminants off of the connections. They said that it will take all the oxidation of the connector, but will not make it shiny, which in their opinion is not necessary to get a good connection.
On the connections which are open to outside abuse, salt, water etc. they would recommend S5 to coat the connections to keep them good for a long time.
She said to use the spray as it will clean the part and help float the contaminants away. The 100 liquid is much thicker and the excess has to be wiped away.
So I order the DN5S-6N 5oz can & SN5S-6n 5oz can.
Hope that helps others in their quest to use the right product.