Dash grounds mess by PO?

[dobryan]

So I've been having an issue with a very erratic tach on my '87 that I've tracked down to bad grounding based on the tach dropping out even more when any fan or light is on. I tracked down the instrument cluster ground wire and it goes to this mess of a ground wire connection. There is one wire from this that goes to one of the grounding stars. This cannot be the way VW did this can it? If not what should have been done so I can put it right?

Paging Mark crazyvwvanman.....

_________________
Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[crazyvwvanman]

Yes, that is stock. For 1987 vans that is ground point (81), with about 7 lightweight grounds joining together and then a single heavier ground wire going from it to the ground star (30).

If you look across the very bottom of all the 1987 diagram pages you should find a lot of brown wires that end up at circles with an 81 inside. The 81 is that mass crimp. Then at current track 54-55 you can see a short heavier brown that jumps from an 81 circle over to a circle with a 30 inside.

On one of the first pages of the 87 diagram it lists all the numbers inside of circles and says where they are located.

So your symptom points to a problem at the ground star where the 1 common brown for all those crimped together browns reaches chassis ground.

(Other years have similar mass ground crimps but the number marked inside the circles varies from 81.)

Mark

[dobryan]

Wow never would have thought that was stock. OK I’ll go after the ground star next.

Thanks!
_________________
Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[Paulbeard]

Yeah, there's also a positive crimp/clusterfarce under there (a bunch of white/blue wires all bundled together)…I cut it off, thinking it was a PO blunder and then had to redo it, since that was what VW intended and I had no way to redo it in a more sensible way.
_________________
Currently -> Frida: 87 Tizian Red (mostly) Vanagon GL Westfalia w/ 2.0L ABA conversion
Formerly -> Steward of a 73 Super Beetle (Beater) and 67 Beetle 1300 (Little Max) both names by POs

[Dampcamper]

I'll pitch this again, a supplemental ground wire to a bolted-down connection:

https://www.thesamba.com/vw/gallery/pix/1921532.jpg

I used #14 wire from the bolted down lug at the top of the steering column brace (just to the left of the brake fluid reservoir) to the ground stars, jumpering the two together. I use a stainless toothed lockwasher between bolt head and lug to ensure lots of contact, this is a 6mm / 1/4" size.
If you do the supplemental ground connections out by your headlamp buckets, splice the wire running to the ground stars back into that too, it will provide yet another grounding path for your entire system this way.

Relying on a #8 sheet metal screw for all of your grounds (and with metal that corrodes, at that) is not adequate. If you take your ground stars off, after cleaning them and the chassis metal you might put a light coating of silicone grease on both surfaces before reassembly. This will retard further corrosion.

[Howesight]

Well, Crazyvanman, thanks for your info above. Now I understand why my dual horns will not work when my AC is on - - the current through the grounds for the rad fan is too great. I knew that I would eventually have to use a relay for my dual horns, but it's good to know that the switched side of the relay will need a better ground.
_________________
'86 Syncro Westy SVX

[dobryan]

So I went after the ground clusters this evening.

They didn't look bad at first blush... but the only connection they had to the body was the threads of the screw that held the cluster down. There was paint behind the cluster that only abraded off when I removed the cluster. Not a good long term connection. The threads of the screw were mildly corroded after 32 years and I am sure that was not helping things. I cleaned everything up real good and also added a separate connection to ground by using a male/female connector and a 12 ga wire to a new spot on the frame behind the fuse panel.

Much improved!

I still have a tach drop out when all lights, turn signals, and fans are on so next I will look at the ground wire from that under dash group ground crimp.

_________________
Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[cs44]

[dobryan]