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914World.com _ 914World Garage _ Are wire connections by the shifter live?

Posted by: Yoei66 Mar 7 2005, 12:57 PM

Howdy!
I was getting the light inside the floor mounted defrost lever indicator working last evening,
when I pulled the carpet back. I discovered several electrical connection, which I ASSume are for center console gauges. I have purchased used 914 volt, and oil temp gauges. Will these plugs assist me in hookup? Are these for gauges? Is there a color code somewhere?

yoei66

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Posted by: Elliot Cannon Mar 7 2005, 01:19 PM

I built my own console with new gauges and used the wires you are refering to. I found the wiring diagrams in the Haynes manual and especially Pellican Parts a whole lotta help. There are wires for each gauge, for the lighting in each gauge as well as ground wires. The wires that control the instrument lighting are connected to the headlight switch and are controlled by the reostat that controls the dash lights. Good luck.
Cheers, Elliot

Posted by: Elliot Cannon Mar 7 2005, 01:22 PM

If I remember rite, the black wires are for lighting and the brown wires are of course ground. I can't remember which was which for the gauges but the diagrams should show you which goes where.
Elliot

Posted by: Dave_Darling Mar 7 2005, 01:38 PM

Red/white == "switched" power; +12V when the ignition is on. Run to the voltmeter and oil temp gauge.
Brown == ground. Run to all three gauges, and possibly to the illumination lights if they have two prongs sticking out the back.
Black/blue == instrument illumination power; has +12V when the parking lights or headlights are on. NOTE: On 74+ cars, the wires in the plugs you have for this connection are grey, not black/blue!! On those cars, the center console lights do not dim with the dash lights.
Solid black == "unswitched" power to the clock. Always has +12V.
Green/red (or green/black?) == oil temp signal wire.

...Uh, I think that was it...

--DD

Posted by: Yoei66 Mar 7 2005, 02:04 PM

Thanks Elliot & Dave. Think I'll give this wiring code a try.

Yoei66

Posted by: Yoei66 Mar 7 2005, 03:08 PM

OK, I hooked up the three connections on the oil gauge, 12v, ground, and green/black signal wire. The gauge immedietly pegs to full temp, with or without the green/black wire hooked. In my experience with heavy industral machinery, this would indicate a failed thermocouple, or no thermocouple. Since the gauge package was not part of my 914 origianally, is there even a thermocouple at the other end of the green/black wire, or do I have to add one?

Posted by: Dave_Darling Mar 7 2005, 03:14 PM

No thermocouple; it uses an NTC thermistor.

First guess is you have the wires hooked up incorrectly. "G" is for "Gauge" (or perhaps the German for "signal"??) and not for ground. + would get the +12V, the ground symbol (triangle made up of horizontal lines) would get the ground, and the G would get the signal wire.

Full-deflection means that the signal terminal of the gauge is grounded. BTW, if you squash the sender wire between the motor mount bar and the rubber motor mounts, it can get grounded and peg the gauge. Been there, done that!!

--DD

Posted by: SirAndy Mar 7 2005, 03:15 PM

QUOTE (Yoei66 @ Mar 7 2005, 01:08 PM)
or do I have to add one?

nope, oil-temp sending unit was optional. so you probably don't have one.
it's mounted at the "taco-plate". your engine most likely only has a cover plate there ...

taco-plate and sender:

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Posted by: SirAndy Mar 7 2005, 03:15 PM

nuther ...

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Posted by: SirAndy Mar 7 2005, 03:22 PM

QUOTE (Dave_Darling @ Mar 7 2005, 01:14 PM)
"G" is for "Gauge" (or perhaps the German for "signal"??)

G = Geber = Sender = Sending Unit

Andy

Posted by: Yoei66 Mar 7 2005, 03:45 PM

OK, I re-hooked 12v and ground. Gauge now seems to act normal now. However, still no signal when I start the engine & run for 5 min. Guess I'll have to get a sending unit. I've seen these things on e-bay, made by VDO. they replace a 914 oil drain plug, and have a temp sensor attached. Anyone heard of these, any comments on these?

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Posted by: Rand Mar 7 2005, 04:01 PM

Have you tested the green (red stripe?) signal wire for continuity end to end? I would suspect a bad wire before a faulty sending unit.

I made up a set of long jumper cables with alligator clips that are real handy for this... Disconnect the wire from the terminal at each end, connect a jumper to each end of wire, bring jumper ends together at your mulitmeter... quick and easy test. My signal wire was bad, and I found it was broken under the engine... probably got pinched at one point. May not be your problem, but worth checking before spending time or money on a sending unit.

Posted by: Series9 Mar 7 2005, 04:14 PM

It's easy to modify the taco plate. I went to the hardware store and found a nut that fit the sender and then welded it to my stock plate:

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Posted by: Yoei66 Mar 7 2005, 04:29 PM

Rand:

I have not tested the wires end to end. I see the green/red stripe wire in the engine compartment, see picture. However the green/red stripe wire is not one of the avaliable wires below the center console area. Is the green/black wire the other end? or is the green/red stripe wire hooked up to the temp warning light. I thought this warning light only sent a signal if the engine is over temp, or is this a sender.

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Posted by: SirAndy Mar 7 2005, 05:32 PM

QUOTE (Yoei66 @ Mar 7 2005, 02:29 PM)
or is this a sender.

nope, green/red is for the oil idiot light.

green/black is for the actual oiltemp gauge.

the green black wire connector in the engine comp is on the pass. side, under the battery tray.
it'll come out of the main harness somewhere close to where the wires for the fuel pump come out.
it has a clear/brownish plastic connector boot thing on it.

from there, the wire runs on the underside of the engine to the taco plate (see pic above for the location of the taco plate) ...

most likely, your car WILL NOT have the oil-temp sender ...

instead of the taco-plate with the oil temp sender, you'll most likely see a round, black cover plate with no hole for the sender ...

i'm sure someone here on the board will have a spare one for sale if you ask ...
Andy

Posted by: Rand Mar 7 2005, 06:06 PM

Here's a couple pics from my troubleshooting. The green/black wire (sorry I said red earlier) at back of the oil temp guage should check continuity to end of the wire at the oil temp sending unit. On my car, the wire at the sending unit is just green (no black stripe), but I think the PO may have replaced it. At any rate, you can see what the temp sender unit looks like on my dirty old oily '75 2.0 (directly above the end of my wire/jumper in the 2nd photo)...

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Posted by: Dave_Darling Mar 7 2005, 06:06 PM

QUOTE (SirAndy @ Mar 7 2005, 01:22 PM)
G = Geber = Sender = Sending Unit

Danke, Ahhndy.

For the most part, only the 2.0 engines came with the oil temp senders in the bottom of the sump. The 73+ cars with center consoles also had them. And there were some 72s that had a temp gauge as an option, so they must have had senders as well.

I would consider the option that RS posted--however, I would see if I could somehow tuck the sender up higher and possibly cover it from having cold air flow over it. Probably mucks with the reading--and may expose it to a little more hazard, though certainly not as much as the Tuna Can is exposed. And I do advocate the latter...

--DD

Posted by: Yoei66 Mar 7 2005, 09:17 PM

Thanks for all the advice everyone!!!

I now pretty much know everything I need to do to hook up these gauges.

This forum is excellent!

yoei66