71 k10 questions

[Navistarpower]

I bought a new wiring harness from lmc truck. I bought both for under the hood. My question is on the lighting side of it. There is a black wire that has 2 small fuses in it. What does this connect to? Is it a hot or ground wire?

[pjmoreland]

Welcome! The fuses are likely for the "BATTERY" ammeter gauge, as can be seen in post #7 by VetteVet in this thread:

http://67-72chevytrucks.com/vboard/s...d.php?t=673925

[Navistarpower]

Thank you for the help.

[Navistarpower]

Originally Posted by pjmoreland

Welcome! The fuses are likely for the "BATTERY" ammeter gauge, as can be seen in post #7 by VetteVet in this thread:

http://67-72chevytrucks.com/vboard/s...d.php?t=673925

I tried searching but couldn't find what I was needing. Thank you. I'll figure this site out eventually.

[pjmoreland]

It can be a bit of a challenge to do a search if you don't know what you're searching for! Anyway, I usually just use Google to search this website by putting 67-72chevytrucks.com in the search box along with whatever thing I'm looking for. By the way, schematics are available for download here:

http://67-72chevytrucks.com/vboard/s...d.php?t=185856

[Accelo]

There is a black wire that has 2 small fuses in it. What does this connect to? Is it a hot or ground wire?
Interesting enough both sides of the amp gauge are (hot) and fused.
One fuse comes out of the harness and returnees to the same taped section of wiring.
This is on the drivers side and close to the fender to core support attachment point. Likely you need to do nothing there besides confirm the fuse is installed.

The second fuse is also completely sealed and one end terminates at the black connector on the inner fender next to the battery.
This connection must be perfectly clean for the amp gauge to work.

You can test the function of the gauge by turning on the high beams, without starting the motor, and watch for negative needle deflection.
The first time I trouble shot this circuit it took me hours to identity the fuse function and location.
Very few truck have a functional amp gauge because of the shunt system GM used at the time is so dependent on perfect connections.
It isn't an accident they(GM) went to volt gauges in later years.
Cheers.

[Navistarpower]

Originally Posted by Accelo

There is a black wire that has 2 small fuses in it. What does this connect to? Is it a hot or ground wire?
Interesting enough both sides of the amp gauge are (hot) and fused.
One fuse comes out of the harness and returnees to the same taped section of wiring.
This is on the drivers side and close to the fender to core support attachment point. Likely you need to do nothing there besides confirm the fuse is installed.

The second fuse is also completely sealed and one end terminates at the black connector on the inner fender next to the battery.
This connection must be perfectly clean for the amp gauge to work.

You can test the function of the gauge by turning on the high beams, without starting the motor, and watch for negative needle deflection.
The first time I trouble shot this circuit it took me hours to identity the fuse function and location.
Very few truck have a functional amp gauge because of the shunt system GM used at the time is so dependent on perfect connections.
It isn't an accident they(GM) went to volt gauges in later years.
Cheers.

My truck has a volt guage, so I probably won't use that? The connector on the fender by the battery isn't there.

[Accelo]

You can use one side of the amp gauge circuit to get the voltage reading. Just add a ground to the other terminal. However, many conversions just pull the positive from the Temp gauge next to it.

[Navistarpower]

Originally Posted by Accelo

You can use one side of the amp gauge circuit to get the voltage reading. Just add a ground to the other terminal. However, many conversions just pull the positive from the Temp gauge next to it.

Thank you.