Which side of coil is negative for 620 tach install

[mccuistion]

Hey guys, so I've tried searching all over ratsun and cant find a definitive answer. I'm trying to hook up a speedhut tach and requires I hook the signal wire to the negative thermal of the coil but I cant figure out which side is negative. I've heard that if you turn the car to 'on' that only the positive side will have power but both sides have power. 

 

 

I was wondering if anyone can tell me which side is negative from this picture of my coil. 

Thanks so much for your help!

 

https://ibb.co/S5mLJ87

 

Edited July 10, 2019 by mccuistion

[datzenmike]

Datsun coils are marked + - on the terminals. Your picture failed.

 

There will be a Blue wire on the negative side. There may be a Blue/White stripe also.

[mccuistion]

Just fixed the photo link. Thanks DatzenMike, I will try to take a closer look at the coil. I think that I know what side your talking about that is positive now that i have your info about blue and blue/white. 

[mccuistion]

I just took a flashlight and took a closer look and it is clearly marked + and - on the coil...... I feel like a bit of an idiot now for asking but didn't see it before. 

 

 

Thanks so much for the heads up datzunmike, I'm hooking up my tach right now!

[datzenmike]

Hey, it was an easy fix. 😄

[banzai510(hainz)]

You can always pull the wires and put ignition to ON and see which has 12volts. then youll know which is the positive

 

as most coils you will measure 12volts on each side/as its really just a wire coiled up.

[vicdat]

You can also use your tongue...

 

Vicdat 610

[datzenmike]

... if you are grounded to the car.