914 quit! thismorning, I fixed it but...., What's this thingin the wiring Options

[jd66921]

My 914 quit running this morning. Lost ALL power. I managed to get a meter
and traced it back. This device:

was in the harness just down from the battery. The battery wire comes from the
left, and 4 wires go to the right. It was hot to touch, so I removed it and the
wires. One was shorted to ground so I disconnected it and the car started.
No lights worked, but I was able to get home. I finally found that something was
shorting in the fuse block, and I was able to get everything working again. Oh
yeah, my flaky tach is working again!!

Does anybody know what this thing is? My guess is suppression diode or
something like that. But I don't know how current gates back from the alternator
to the battery??

It is about an inch long and about 1/2 inch wide. It says 12V30A on it. I am glad
it was there, as it limited the current draw and kept the battery from being shorted
too!

Thanks,

Jeff