Relay Board w/7 pin HEI Module

[floppy]

Bender,

Hate to see you give up, although at times it can be tough. Have you not found a rpm signal?

So here's something that deserves explaining:
I changed the input to falling trigger and suddenly all of my problems disappear and it runs great - With ignition control!!!

Is this a good thing or is something else reversed??

[floppy]

Bender,

Hate to ask but how did you cook the relay board??? Could you go to a 4-pin with fuel only for now?

[Bender142]

I think I put batt voltage across pin 24, smoked the trace on the relay board.

This project has been bogged down for too long, I need the vehicle, not a goose chase. At lease I had it running with a factory ECM. I might go back to that set up when I cool down or just drop a carb on and go.

I tried both trigger circuits, adjusting R52 & R56, added the 2n222 mod, still no RPM signal on the vehicle. Every config tested fine on the stim. I've been over the board with a good magnifying lens and a fine toothed comb. Excess flux cleaned, no solder bridges, etc, etc,........hooked up each wire to the rellay board individually and tested continuity........I finally realize what people mean when they say that MS is not for everyone

[floppy]

I have a couple of jumpers past fried traces, you're not alone there.

Sounds like you might be best to put it down for a while. Maybe you can pick it back up later, your perseverance certainly gets tested to the limit.

Thinking about the rpm, are D1 and D2 jumpered? VR is correct polarity and module is good?

We'll see how long you can leave it alone

[Bender142]

D1 & D2 are both jumpered and I have a new module. Came to find out the old module was fine so now I have two known good 7-pin modules. A friend has also loaned me 7-pin and 4-pin dizzys so I can spin them separate from the engine. I rigged up both and still did not seeing the RPM in MT. I pinned out all the wiring to verify continuity (everything was correct per the wiring diagram). I ran an external relay for the 5v supply to the 'B' pin on the module. The relay was wired per the 7-pin diagram. The settings in MT were per the manual's 7-pin HEI instructions.

I did not try the falling trigger before I smoked the relay board. I could wire around it but this has become a needle in a hay stack kind of thing. I'm looking at other options and will take your advice; I'm setting it down for now.

Thanks for your help.

[floppy]

I completely respect your decision.

One last thing, I you like you could send it to me and I will trouble-shoot for you? PM me if you are interested...

Later, Mark

[Bender142]

I'm ready to put the whole mess on a flatbed and send it one way. You could take the bed off, shorten the frame, cage it, lift it, and head up in the hills.

I really appreciate the offer and I'll think it over. I was just out in the shop making an adapter for an old 2bbl. As much as I don't want to go back to a carb, I also don't want to keep waisting more itme. I could send you the MS-II, relay board, and dizzy but the problem may lie else where. On the positive side, if you could get those items to play nice together, then I'd be sure the problem lies in my wiring or settings.

The other side of this thing is the fact that I can't figure it out myself. You've got your projects and my problems would only distract your time.

Again, I really appreciate the offer. I'll get back to you.

Thanks