Decklid license plate light ground

[tomfreo]

Since removing and painting the decklid some months ago I've had a dodgy license plate light. At first the light would only come on with the lid closed, which was ok while it lasted. Now it doesn't come on at all.

At the time of painting and rewiring the light, I made sure the light ground on the decklid had a nice shiny bit of metal to sit on. I guessed somewhere around the hinges too would need to be paint-free and thought I left adequate metal-to-metal contact. Now that it doesn't work, I'm thinking I just didn't do a good enough job of ensuring the light had a way to ground.

Question is, how exactly does the light find ground? Which parts of the decklid where it attaches to the body needs to be clean of paint? Or, at least, when the beetle came out of the factory, how did light find ground? Am I going to have to remove the decklid to get a good ground?
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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[sjbartnik]

Before you make yourself crazy chasing grounds, make sure the bulb hasn't died.

Also make sure the bulb has a snug connection into its socket. The power input to the bulb is through the point on the base but the ground is basically the rest of the bulb's metal casing. It needs to make good contact with the housing to have a good ground.

You can test your ground theory with a length of jumper wire, just turn the lights on, run your jumper wire from battery negative to the bulb housing and see if that makes the light come on. If it does, then bad ground is confirmed. If not, then your problem is elsewhere.

Your theory of how it grounds is correct; bulb housing grounds to the decklid by contact through the mounting point, then the decklid grounds to the rest of the body through the hinges.
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1965 Volkswagen 1500 Variant S
2000 Kawasaki W650

[catahoula lou]

You can also clean the inside of the bulb holder using a battery terminal brush and electrical cleaning spray. Might also check base of bulb for oxidation and clean that as well, assuming that the problem's at that location...

Thom
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1 great wife
2 Catahoula Leopard Dogs (Mahogany Star and Spartan) - RIP Lucy, Braveheart, & Dusty!
1 1959 mango green Ragtop Bug (the "Mango")
1 1958 pantina red Lowlight Ghia (the "Chili Pepper")

Still looking for:
(1) My Dad's 1955 356 (he raced it amateur-class at Riverside and other courses during 1950s),
(2) My parent's black 1955 hardtop bug (CA license plate FWC 201 or FWG 201), and
(3) My parent's agave green 1957 ragtop bug (CA license plate LFK 734).

[grandpa pete]

New shiny paint doesn't make good grounds . This has aggravated more than one restorer .
How well did you paint the decklid hinges ?
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63 two fold rag
66 sedan delivery Type 6

http://www.thesamba.com/vw/forum/viewtopic.php?t=569619&highlight=sedan+delivery

[sludge20]

I had similar issues a while back. I corrected them by installing a small, hidden ground wire on the passenger side deck lid hinge bolt and ran it to the firewall bracket mount.

[Johnous]

I literally fixed this exact issue on my 66 this morning before renewing my inspection!

Others' advice is correct: get a test light, and make sure the bulb is getting power before chasing grounds. If you get power to the plate light socket, you know its the ground. If you don't get power, that is your issue.

If you are getting power, make sure your bulb is for 6v and is in good working order. If the bulb is good (I used alligator clips to connect it directly to the battery for my test), then the grounds are indeed the culprit. The metal carrier for the plate light is grounded by the mounting screws.

You will need to make sure to chase out the screw holes, and that there is some exposed metal right around the screw mounting holes. This allows the metal bulb carrier to contact the car body. The bolts that hold the decklid hinges to the car should make metal to metal contact and ground the decklid.


If you arent getting power, the license plate light on your car hooks to the right tail light (http://www.thesamba.com/vw/archives/info/wiring/bug60.jpg). Start at that connector with the test light and work towards your license plate light until you find the fault.

[tomfreo]

I haven't yet had time to work on the light but thanks for all the tips. I'm pretty sure it's a grounds issue but I'll be sure to check there's power to the light, and that the bulb and contacts are good.

Otherwise I suppose it's easy enough to find out if there's a path to ground from where the ground wire is attached to the decklid.

I think it's probably an issue with continuity through the hinges. I'm curious to know if anyone knows how VW ensured continuity through the hinges, what part of the assembly they left bare of paint.
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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[Cusser]