Aux grounding my instrument panel

[tech71]

I have never done this particular task before and was wondering where the best place to attach a secondary ground would be?

#1 pic: an unused preinstalled ground tab shown?

#2 pic: under these knurled nuts that I believe retain the fuel/temp gauges?

#3 pic: under this attach screw?

Any recommendation?

Thanks in advance, Mikey

[tech71]

Never mind guys, quick Google search yielded an answer, going to go under the little knurled nuts as recommended by our editor, The venerable Mike Self. Sorry for wasting server space?

Edited July 13, 2022 by tech71

[Son of Marty]

What I do is make a y with 2 small ring terminals on the arms and connect them to under the pill nuts and ground the tail to the metal at the back of the instrument cavity leaving enough slack so you can get the cluster back in with it hooked up, In the middle of the ground wire I add a spade connector so I can disconnect the ground with out unscrewing anything. Mintgrun made a copper bar to bridge between the 2 pill nuts and filed one end to take a spade terminal, nice piece of work that.

[2002#3]

You can never have too many guitars or grounds.  Every time you add a ground, the white light of the metaphysical universe fills your mental, physical, spiritual, and emotional chakras with enlightenment to the point of realizing your true inner '02 self.

[John76]

Does anyone know what this spade connection is for??

It is not grounded to anything in the dash pod.

 

[jimk]

If there is continuity between the unused spade connector and pin 9 (o'clock) on the main connector then why not use it.  (Pin 9 has to always be a good ground or the entire dash would be dead electrically, lights, tach, etc.).

I grounded my gauges in 1973 and don't recall the spade terminal but intend on looking at a spare dash that I have.

 

Edit: Disregard my ramblings about the spade connector.  The spare late model dash not only doesn't have the connector, but also there is no continuity between the trace and pin 9.

Edited July 13, 2022 by jimk

[tech71]

This should work, making a run to town so will see if there's any improvement to temp gauge.

[Mike Self]

That'll work just fine.  For my ground point I used one of the small studs that holds the heater box in place.  Took a terminal that's used to adapt male spade terminal to a ring terminal stud (as on older coils) and fastened the spade terminal under the nut.  With enough slack in the wire, you can then unplug it when removing the instrument cluster.

 

mike

[tech71]

Temp gauge is sorted! Nice, thanks guys.

Edited July 13, 2022 by tech71

[2002#3]

Your work looks quite nice.  Make sure the wire (not shown) from the female blue spade end to wherever you select to attach to  ground is sufficiently long to allow you to easily pull the instrument cluster out far enough to disconnect the spade whenever you remove the instrument cluster.  I made my first ground wires so short I could not reach behind the cluster and disconnect it as the cluster was being removed.  Duh.  Easy fix.

 

Those several connections behind and to the cluster are difficult enough to reach and maneuver during cluster removal and installation.  Don't let your new ground contribute to the issue.

[02jake]

thanks for posting this. Just going through the same issue. All tests pointed to a bad fuel gauge. Housing needs to be grounded as well.

 

[AlfaBMWGuy]

4 hours ago, John76 said:

Does anyone know what this spade connection is for??

It is not grounded to anything in the dash pod.

 

 

Pretty sure that spade is for the parking brake warning light for '74+ '02s.  Wasn't needed before '74 since that light was only for brake failure (low fluid, not sure of anything beyond that).  If you have that spade on a pre-'74 non-fake woodgrain, non-crosshair gauge face cluster, then that bit of your cluster is from a '74+ car.  On a '74+ car, you'd have a wire to connect to that spade.

 

-Gary

Edited July 13, 2022 by AlfaBMWGuy

[jimk]

Spade terminal is connected to circuit 226 and has something to do with the interlock system .bmw2002-usa-1975.pdf