troubleshooting turn signals

[midevilone]

Turn signals are not working.
I have checked the distribution box and here is the state of things.

We are getting power to the distribution box and appropriate power on F, D, C. But no pulsing power on Pin G.
How do I troubleshoot further and presumably replace a dead component?
(we have the sparton switch on the column)

[midevilone]

Note, in the image pin f has the wire unhooked. that was just the state of things at the time of pic.

[Barrman]

Sorry I can't help you with the old relay system. Except with the basics like are all the lights on the truck that are used by the blinker system working? Do you have good grounds at all the lights and at the relay box?

[rboltz]

If you want to get into the weeds on this, see here;

http://www.m715zone.com/vb/pages/man...ck_distbox.pdf

[Don Cavey]

Thanks to Ron for this excellent schematic, I was able to convert my truck from the electronic box (which was Kaput) back to an NOS early distribution box. It worked the first time and no smoke or burned wires.

My two trucks that I drove in the army were early trucks with the distribution box, Sparton turn-signal switch and not electronic.

Thanks again, Ron.

[brute4c]

Second that, Ron has provided EXCELLENT resources for the electrical that is far better than the factory stuff and way better than I could ever come up with...he does not get enough praise for this.

[rboltz]

Second that, Ron has provided EXCELLENT resources for the electrical that is far better than the factory stuff and way better than I could ever come up with...he does not get enough praise for this.

Thanks for the comments. While off topic, I also have a schematic of electrical for the M-44A2 series of trucks which includes the M-35. If anyone needs one, I can e-mail it in PDF.

Still working on the M-37 series.

[midevilone]

I now have pulsing power on terminal G
And the sparton indicator light pulses as well

But still no turn signals. Have 3 way in ser drive and park mode

Brake lights work when hitting the brake so we know the wiring etc is good. But thats where the good news ends. Anything else I can check?

[midevilone]

Jumping a wire from g to a respective bulb causes it to flash.

[rboltz]

Jumping a wire from g to a respective bulb causes it to flash.

I would assume, not being there to check, you have bad relay(s) in the distribution box. They do fail and I don't think replaceable. You should consider a swap to the solid state system.