Gas Gauge... again.

[bradey bunch]

Oh, and david58, what are the three red arrows pointing at? The 412 gauge is somewhat different than that gauge.

[david58]

Post a pic of the back on your gauge so I can see it.

[MGVWfan]

Hmmm! All THREE warning lamps are out...that would point to the common +12V Ignition feed to the lamp/clock cluster. It's a black wire, number 15, and fused by S11 (8 Amp), at least in the US 1973 412 version.

BTW, if you need a wiring diagram to figure things out, go to:

http://www.vintagebus.com/wiring/index.html

Scroll down to the "411/412" section, and select your year and type (US or not). The diagrams are split into multiple pages, so you may have to go down the line to find the page with the alt lamp circuit. If yours is a US 1974, then this is the page of interest...

http://www.vintagebus.com/wiring/Type_4 ... 1973-2.jpg

The legend is Page 5, BTW. Also, some of the diagrams (like this one) have a German legend, so you may have to use Babelfish to translate.

The Alt lamp is K2. A black wire from S11 to the gauge cluster feeds K2, K3, and K5, the Alt, Oil Pressure, and Blinker lamps, and the fuel gauge, and another black wire from S11 feeds the back-up lamps, and the Kickdown solenoid. A green wire from S11 feeds the turn signal blinker relay through the emergency flasher switch. Funny thing, on the '74, the brake warn lamp is not fed by the same line from S11...hmmm, on my '73 they're on the same fuse. Oh well.

If S11's blown, you get none of the above. If it's just the line to the gauge cluster, you get no Alt, Oil Press, or Blinker lamps on the gauge cluster, and no fuel gauge function. It's possible also that the connector which feeds K2 and K5 is off or bad, affecting only those two. I've got both the '72 and earlier and the '73 and later right gauge clusters in the attic, I'll go fish them out and post images of the backsides for further discussion. Note that the 4-lamp (Blinker, Oil, Alt, Beam) '73 and later cluster has a thermal fuel gauge with voltage regulator, like most US cars, and the 6-lamp (two blinker, Oil, Alt, Beam, and Parking Lamp lights) '72 and earlier cluster has a magnetic fuel gauge and NO voltage regulator, like older VW's and GM products.

[bradey bunch]

I have been studying the diagrams alot, and my car uses the later gauges. What is interesting is that the dash lights, (blinker, illumination) and fuel gauge work... there is power to the three black wires at the back of the gauge, as well as the red one for the clock. The fuses are good... but when I removed the fuse for the dash lights... and turned on the ignition, the alt and brake light lit up and would not go off (even when car is started) until i replaced the fuse. WTF. I am looking at the wiring diagram, and it seems that on the '73s the brake light and alt light are connected by the same blue wire, so I am curious if my car is a transition month or something, as that could be why they both lit up...

[bradey bunch]

OK. I had some time to work on my car, and the alternator problem was traced back to the plug in the engine bay from the alternator! I guess I was clumsy while doing something in there and knocked it off. Now, the brake warning light and the alternator light work (and it now charges...)! Thanks to everyone for their help, especially david58 with his awesome writeups on testing.

Braden

[MGVWfan]

Glad you figured it out

[bradey bunch]

Just for reference (I have allready solved my problems..) I have a picture of the early fuel gauge/clock with the correct for '71 wire stubs attached. Mine is different, but at the moment it is in the car so I can not get any photos of the back.

Braden

[MGVWfan]

This pic aughta go on a sticky up top...good of you to post it! Still digging in the attic for my instrument clusters

[raygreenwood]

I just dug out a whole box of them Sunday. Ray