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Posted by: steuspeed Jul 27 2011, 07:41 PM

So I'm fixin the little things on my new 914. The temp gauge is dead. I poked around on the net and did some searches on 914 World. I can't seem to find the info I'm looking for.

Located the taco plate and the wire running up into the engine compartment. There is a connector there so I hooked up a volt meter to the wire to see if the sender would give me a voltage reading that moved after I started the car. I got 0-.1 Volts after several minutes. Is my sender dead? Should I be seeing a voltage range or am I way off base with my test?

Stewart

Posted by: Cap'n Krusty Jul 27 2011, 07:56 PM

It's a variable resistance ground, not a positive voltage source.

The Cap'n

Posted by: steuspeed Jul 27 2011, 08:51 PM

Okay Cap'n.

So should I see 12V coming from the gauge to the sender?

If so I should be able to hook up my Volt meter battery -> sender wire and measure resistance. I should see the value change as the motor warms up.

Posted by: MikeM Jul 28 2011, 08:24 AM

Don't order a sending unit from A.A.
I've been waiting for mine for almost 6 weeks....
Mike

Posted by: gasman Jul 28 2011, 08:29 AM

Oil temp sending units are NLA ..... since I recently I tried to find one

Posted by: 76-914 Jul 28 2011, 08:51 AM

I just installed one 2 days ago. I bought mine with the gage from eGauges.com. Yes, it is VDO.

Posted by: MikeM Jul 28 2011, 09:22 AM

The one I'm waiting for is the aftermarket sender to go with the VDO gauge.
It was supposed to come with the gauge but they forgot to ship it.
Weeks later...no sender. Live and learn.
Mike

Posted by: Cap'n Krusty Jul 28 2011, 09:51 AM

The gauge has 3 wires. One is 12v +, one is ground, and the third is the variable ground signal from the sender. Verify you have 12v + at the (+) terminal and ground at the ground terminal (marked with the usual ground symbol). Only then can you test the system. Remove the sender wire from the instrument and apply ground to the tab. Key on. If you see the needle move, the gauge is probably at least functional, accuracy is still an issue. Remove the ground wire, reconnect the sender wire, and get under the car. Remove the wire from the switch and ground it. Look at the gauge. You should have the same movement as in the previous test. If not, try grounding the wire where it joins the harness below the battery. If it works, then the wire from the sender to the junction is bad, if not, you may have an issue between the junction and the gauge.

If the wiring and gauge are OK, then you likely have a sender issue. You can use ONLY a sender made for that instrument. You can't just get any old sender, as the gauge won't read correctly.

The Cap'n