Help needed... Autometer Gauge Dash Wiring

[Joe Arioto]

Okay, we are stuck at dash wiring for our MK4 build.

We have wired the autometer gauges per the instructions (I think). See pics below and let me know if you have any input.

Seems like the gauges are not getting power. Keep in mind, we are total noobs and have no prior experience... so don't be afraid to mention the obvious, it's not obvious to us.

An observation I had is that the volt meter seems not to have any place to ground. Seems like an issue to me, but I might be misunderstanding too.
Thanks in advance for any insights or help.

Back of the dash:


Small gauge cluster:


Speedometer:


Tachometer:


Not sure if this is the issue or not but, as you can see... we have not wired the headlights and turn indicators:


Lastly, we cannot figure out where to connect the green wire for the fan. I believe this is the thermostat switch to turn the fan on:

[TMartinLVNV]

I think you tach wiring may be messing you up. I had the same problem. Click here for a fix: https://thefactoryfiveforum.com/show...l=1#post383523

There are two green wires available in the RF harness for triggering your fan. You can use either one. I have the Holley Sniper and it has an output for triggering the fan. If you are using an thermostatic switch, then that it what you will use.

The red and green condoms are for your gauge light bulbs. I used the red on mine.

You are using Scotchlok wire splices. They are notorious for not fully piercing the insulation of the wire that you are jumping. It may be the cause of your power problem. I would recommend using butt connectors with the dual wire ends twisted together. If you need to, go one size up in the butt connector to fit two wires into it, on the opposite side that has one wire, cut the insulation off further up than normal. Then double the wire over itself so that you get a good crimp.

You need to use the ground on the voltmeter. It is the middle spade on the back.

[weendoggy]

You can connect ALL grounds on gauges in series. Voltmeter will have just power and ground (light too). You can power all the gauges from the voltmeter in series as well. I use non-insulated eyes and crimp both wires from the ring to daisy chain along. Use heat shrink on each one and even solder my connections. I'm also not a fan (no pun) of Scotchlok splices. Those are emergency only fixes.

You have to find out if the RF has a built in relay (I think it does) for the fan. Do not connect it direct if it's powered. Go through a relay and it can be activated either ground (my preference) or hot.

Tach is going to get power from neg. side of coil if you use a standard ignition (no CD box) and if you use a CD box it has it's dedicated lead for the tach. You will NOT use the neg. coil terminal with a CD box for the tach.

To neaten up the loose connecting dash/chassis wires I suggest a good connector such as Metri-Pack. That way it's a single plug. I think I have several for my dash.

Good luck.

[Joe Arioto]

Thanks for the help guys. Terry, my first thought... as in very first thought, when I read the red/green condoms comment was, "crap, I need to take those pictures down NOW!" But... in my ignorance I have room to learn and others might benefit as well. Thanks for the clarity. I think we will go with Red too.

I still can't get the gauges to respond when I have the harness plugged in. So, we're still sleuthing.

weendoggy, I'll neaten things up as suggested. It feels really cluttered to me. As I get a little older, I'm realizing I have some OCD tendencies, and I think just knowing those wires look like that back there would drive me nuts... even if I couldn't see it. Okay, as I type that I think I just confirmed serious OCD.

I'll keep everyone posted as I make progress.

[johnnybgoode]

Thanks for the help guys. Terry, my first thought... as in very first thought, when I read the red/green condoms comment was, "crap, I need to take those pictures down NOW!" But... in my ignorance I have room to learn and others might benefit as well. Thanks for the clarity. I think we will go with Red too.

I still can't get the gauges to respond when I have the harness plugged in. So, we're still sleuthing.

weendoggy, I'll neaten things up as suggested. It feels really cluttered to me. As I get a little older, I'm realizing I have some OCD tendencies, and I think just knowing those wires look like that back there would drive me nuts... even if I couldn't see it. Okay, as I type that I think I just confirmed serious OCD.

I'll keep everyone posted as I make progress.

I went with the red as well. The blue and green don't really change the colour of the lights that much. Here's what the red looks like. Scott

New Dash 082.jpg

[weendoggy]

I still can't get the gauges to respond when I have the harness plugged in. So, we're still sleuthing.

The first thing you need is 12v. power to the gauges ("I" side) when key is ON. The "S" terminal comes from the sending unit direct. To test if the gauge is working, make sure you have 12v. there (key ON), and you can then momentarily ground the "S" terminal and it should peg the gauge. This tells you the gauge is working. To test the wiring to that gauge, disconnect the sender wire and while the key power is still on, momentarily ground that lead and watch the gauge. It should peg the gauge as well. Insure you have the ground side of the gauge secure as well. If all this works, the wiring is good.

[TMartinLVNV]

The first thing you need is 12v. power to the gauges ("I" side) when key is ON. The "S" terminal comes from the sending unit direct. To test if the gauge is working, make sure you have 12v. there (key ON), and you can then momentarily ground the "S" terminal and it should peg the gauge. This tells you the gauge is working. To test the wiring to that gauge, disconnect the sender wire and while the key power is still on, momentarily ground that lead and watch the gauge. It should peg the gauge as well. Insure you have the ground side of the gauge secure as well. If all this works, the wiring is good.

Papa aka Doc aka Pete taught me this. A 12v lantern battery works great for testing your dash connections. Actually, all electrical stuff on the car.

https://www.amazon.com/Rayovac-926-G...43407050&psc=1