r13420

I recently purchased a OBC tachometer and 4-stalk steering column stalks/levers (w/OBC control) for my 1992 964 C4. I know I should have removed my original tachometer to see if the original connector for the OBC tachometer was there before I bought all these parts, but I didn't since a few forums on here noted that one should be already wired in. Well, I recently removed my original tachometer to see if the connector/pigtail harness was there, ready to click into the OBC tachometer, and I was totally bummed to see that there wasn't one wired in already.

So, I found a (cut) OBC tachometer connector on Ebay, (the one in white shown in the photo below) but am having a hell of a time trying to figure out how to splice the cut pigtail I got into the main wiring harness.



A few guys here have noted that they have done this on their 964's and it should be fairly easy, but I guess not for me! I have already read the forum thread/article from p-car/pelican parts, but that was for a 993, so I'm not sure if the directions would apply for a 1992 964? Even if these directions do apply for a 964, they are complicated as hell! I have searched all over the web for other forum threads or articles to no avail.
Could you guys lend a helping hand? Or anyone local in Southern California that would do the wiring for me? I am willing to pay for your work. I am beyond frustrated at this point and am regretting buying all these expensive parts.

Thanks rennlisters!!!!

r13420

Bump.

bb964

Surprising you don't have the second plug, my '92 has it and I have installed the OBC tach long time ago.

At this point, I would just leave it alone, would not want to cut/splice the wiring harness just for the OBC.

r13420

When you took out your original tach, your '92 already had the OBC tach plug already wired in just sitting there? If so, that's weird that mine didn't have this.

bb964

Yes, there was an extra plug so completely plug and play, no modification whatsoever. 993's were no longer pre-wired but 964's were AFAIK.

budge96

I would check inside the dash I have rewired both 964 and 993's with replacement harnesses and at least on the 993 I recently noticed the additional plug I was under the impression it was for a tip transmission Speedo but trip computer tach is possible ..
I know the '91 , '92 and '94 Turbo hell the '96 Twin Turbo as well have these trip computers standard .
I think there is an additional relay or controller as well behind the gauges near the gong relay , just an FYI ..this is not something I would care to try and splice into the harness..
As far as I know it was available as an option on others ....Bert

Nikolaus964

My 91 car also had the additional connector - is it possible you missed it? The connector was covered in foam and neatly stored away using a zip tie to ensure there was no rattle from factory behind the dashboard.

bb964

I like the OBC, especially the speed display and miles to empty. If the plug is not there, would not go through the trouble of cutting (possibly brittle) wires as OBC functionality is very basic.
These cars are classic at this point and - less modifications is more IMHO.

r13420

Thanks guys for the helpful input! I am going to take another look this weekend. It is possible that I may have missed it. I had installed the 4-column stalk weeks ago and have been trying to figure out the tach wiring issue since. So close, yet so far from finishing.

Lorenfb

Wiring info: