WCR postmortum, Alternator Testing Options

[914werke]

(IMG:style_emoticons/default/dry.gif)
So I finally got a day to mess with the LE & fix the charging failure.
To recap while out on the drive to a scenic lake for a grupe photo shot,
the car burned through the charge on the battery.
With help from my fellow participants we got the car charged, tighten the alt belt that was slightly loose & swapped a voltage regulator for good measure.
To no avail ... (IMG:style_emoticons/default/sad.gif)
We limped back to the hotel & while relaxing with a cold beverage determined that the failure could be chalked up to a simple bulb burned out in the combo gauge. (IMG:style_emoticons/default/headbang.gif)

Weeell, not exactly.

After pulling the gauge it appears that the bulb WAS'NT burned out.
Strangely instead of the bulb lighting brightly as soon as the key is turned,
it takes a second to begin to light and then it only energizes the bulb ...barely. as if it isnt getting full wattage (IMG:style_emoticons/default/confused24.gif)
It is so dim that you cant tell that it is actually lighting past the colored lens.

What the hell?

[McMark]

Poor ground or corroded connection?

[ThePaintedMan]

(IMG:style_emoticons/default/agree.gif) Would almost have to be with those symptoms. New ground straps work wonders.

https://www.summitracing.com/parts/tay-20308/overview/

[914werke]

1st thing i checked, more for loosening ala nut n bolt. All the grounds (& new strap) have been over MULTIPLE times.
Bright & shiney

[McMark]

1) Resistance check the blue wire at the gauge (unplugged) to the voltage reg. connection (D+, forward-right, VR unplugged).
2) Resistance check D- at the VR connection (single rear pin, VR unplugged) to alternator body.
3) Also try the light with an temporary ground from the alternator body to B- and see if it intensifies.
**Pull the oval plastic plug in the engine tin for easy access to the alternator body.

I forgot the charge light doesn't technically have a ground. It's a weird setup where the red/white wire on one side is key-on 12v and the blue wire on the other side is from the alternator. When everything is working and the car is running, both wires are 12v and neither are ground, so the light doesn't illuminate. If one side is lower than the other you have partial voltage. So if the red/white wire is 12v (battery voltage) and the blue wire is 10v (failing alternator) you'll get a dim (2v) light.

The point is that when the key is on and the engine's not running, the red/white wire is 12v (battery voltage) and the blue wire becomes the ground path. If you're getting a dim light it's either low voltage on the red/white wire (low battery voltage or resistance in the line), or poor ground via the blue wire.

I'm sure it's not battery voltage, the red/white wire is unlikely but still a possibility, the blue wire is suspect (especially in the relay panel, test 1 as above), also the alternator harness (test 2 as above) and the alternator grounding itself (test 3 as above).

[jim_hoyland]

Did you test the bulb socket for continuity ? IIRC, some of those sockets are not always 100% reliable

Good luck with this (IMG:style_emoticons/default/smile.gif)

[JRust]

It's just the LE wcr curse dude. (IMG:style_emoticons/default/happy11.gif) I think this just means you need to install that big4 you've been sitting on for years. That will fix your problem (IMG:style_emoticons/default/aktion035.gif)

I also hold McMark personally responsible for it. If he had come he could have fixed it like he does every WCR (IMG:style_emoticons/default/poke.gif)

[McMark]

(IMG:style_emoticons/default/av-943.gif) I like you Jamie. (IMG:style_emoticons/default/biggrin.gif)