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Hello All,
It's always something with these old trucks. I just completed my transmission fix a couple of weeks ago, and before I did a test drive I decided to check all my lights. To my surprise the turn signals and emergency flashers have stopped working. Since I run the Painless Performance harness I began troubleshooting, and so far everything is pointing to the turn signal switch-the sole component I did NOT replace when I installed my harness.

Saturday offers temps in the mid 60s before the next snow Sunday night. I hope to solve this issue soon w/o buying another switch, although the Signal Stat model I run is plentiful on eBay....

More to follow,
Gary

Gary,
We put mine back in action yesterday. Maybe our trucks switch off?!

I have an ancient switch if you need parts. I'll send a photo next time I'm down at the Shop.

The rebuilt trans shifts well, but it never shifted too badly in the past. Considering how far the syncros were worn I'm surprised it worked so well. It is quieter now .

We're doing Cars and Coffee tomorrow so I can go park with the prancey horse cars. The OD sets off well with the red !

Andy

I recently replaced my non-functional Signal Stat 600 with a "Stat 900, with a new 24 V flasher from Grainger. Works for me.

all the best....

Thanks guys,
I'm getting back to this tomorrow afternoon, and I may have finally figured it out.
More to follow,
Gary

my turn signal switch died today also
it was an old one that came with the truck

I am going to replace it

yay I get to cut apart my new wiring harness I just finished

Finally, success! After repeated troubleshooting within my level of experience, and a couple of calls to Painless Performance, I now have working signals and flashers again. One of the flasher motors failed, and while I'd replaced one unit w/o success and still had no power at the flasher plugs on the box, Painless instructed me to make two jumper wires with spade terminals to bypass the flasher motor itself, using the jumper wires in their place. I did so, and the lights lit up, so I replaced the emergency side jumper wire with one of the original flasher motors that promptly failed and blew the fuse. I replaced the fuse then tried another flasher motor that worked. So, half way home. I then swapped the turn signal side jumper wire with a new flasher unit and behold-turn signals now work too!

So I cleaned up all of the loose wiring and tidied up the cab. I also ordered a couple of braided ground wires that I will install in order to ensure I have solid grounds on the M. Jason at Painless advised that this is one of the most common problems-poor grounds.

Anyway, glad this is done. TBD on the next repair to be done....
Gary

Just curious, What painless wiring harness are you using? a universal one? a custom made?

Hey Juan, I have the 8 circuit Painless Harness, it works flawless.

Mine is the Painless Performance non-GM 10104 kit. I also used their headlight switch until I can find the time to graph the wires into the military headlight switch.
Gary

I have the original Signal Stat 600 on my truck, as well ('63 M-37B1). I have no front marker lights, turn signals, 4 ways or brake lights. Would a bad 600 unit also be causing the negative function of the brake lights or is that an additional failure of something else?

I have an older 900 unit that bench tested fine with 12 volts. What do I need to do to it, if anything, to use it with 24 volts?

Thanks,
John

You just need a 24 volt flasher. I got mine from Grainger.

NV

Oh, and replace the tiny bulb with a 24 volt bulb. Mine from NAPA

Do I need a new flasher?

Also, consulted the wiring diagram from the TM (the one that covers the B-1). How do I match up wires to the new 900 Signal Stat?? The diagram just shows the wires on the 600 unit as being A,B, H or whatever and that they connect to the corresponding stations on the relay box. But how do you know how to connect the wires if upgrading the a 900 unit, or using a unit from a newer MV? For instance, I can grab the switch and box out of an M-816 that is being parted out ... but how would it connect??? I don't really want to butcher up my existing harness....

so much for this being simple.

I removed my relay box, with the connectors on each side, and just put in a 900 and it works fine. I have some posts about it a month or so ago. I have no idea how to hook a signal stat to the old box. Mine works great. Why use the box, when just a S'Stat 900 along is fool proof?

NV

Well, that's a good question and I hadn't thought of doing that. My day job is working for a major military Systems Command so I guess it's programmed into me not to mess with engineering configurations without reams of documentation and authorization ... Thanks for giving me an alternative!