RJM Harness Fuses

[flousberg]

Ron o died going down the interstate yesterday. Instant loss of power. Thought it was fuel but pressure is fine. Found the top 20 amp fuse in my RJM harness blown, changed and it blew right away. Does anyone have a wiring diagram for this harness so I can figure this out? I assume something is going to ground.

 

[flousberg]

I got the red wire from the second solenoid is going to ground. That is what is blowing the fuses. I don't know where this wire goes to.

 

[flousberg]

Here is what I have so far. Put in a new 20 amp fuse for the ignition. Turn key on, relay comes in, relay gets quite hot, coil gets smoking hot, to the point you cannot touch. Then fuse blows. Coil is new. Unplug coil and nothing gets hot and fuse never blows. I changed out TFI with old one I had, did not make a difference. It is like coil is always to ground. TFI controls coil, correct? Not sure where to go from here.

 

[bigmuddy]

RJM was bought out by Ron Francis. I believe they have a wiring schematic online.

 

[flousberg]

Just got done doing some more trouble shooting. Doesn't matter if I have the TFI plugged in or not fuse blows if coil is plugged in. Hot side of coil has 12 V to it. Ground side is 0 ohms with key off and 115-230 with key on. Fuse blows immediately. I think it has something todo with the ground side of the coil. Put new coil in, doesn't make a difference. I believe the ground side goes to TFI and EEC. I think that is it. My understanding is the coil grounds when it fires.

 

[Viperwolf1]

Disconnect your tach and see if you still have 0 Ohms with key off.

 

[flousberg]

Phil,
I finally found those on the web. So I kept blowing the fuses, thought it was the coil. Replaced coil, still blew fuses. Unhooked TFI and still blew fuses when coil was plugged in. I hook coil and it was fine. Decided to unhook computer. Hooked up coil, no blown fuse. Hooked up TFI, no blown fuse. Saw on YouTube video you can get spark without computer hooked up, tried that, no spark. Hooked computer back up, no blown fuses anymore. No idea what was going on here. Still no spark. Since new coil, replaced TFI, no spark, replaced distributor pickup, no spark. Took test light in coil and saw I was getting pulse, so TFI, pickup is good and signal to coil is good. Took new coil back and warrantied it for another one, fired right up. I think it was coil the entire time first old then new. Not sure about fuses, anyway the computer grounded that circuit and got stuck? When I disconnected it rest? Anyway, I now fully understand the entire ignition system and how to trouble shoot with test light and spark indicator.