5-pin vrs 4-pin electronic module

[MoparPat]

My son has a 78 Dodge Motorhome with a 440 in it, it quite running, he took off the ignition module and has the 5 pin, assuming it's got the ecu for being a 1978. He tried using the 4 pin electronic ignition module and it does not work. Could that be the problem he needs the 5 pin, thanks for your help.

 

[3404speed]

http://www.forabodiesonly.com/mopar/showthread.php?t=90499


some more info:
http://www.allpar.com/fix/electronic-ignition.html

 

[cudamark]

So you've determined that there is no spark? First thing is to check the ballast resistor. A simple test light will do. Next most likely is a bad plug, wire, or power source. Least likely is the pickup coil in the distributor. In almost 40 years of playing with these, I think I've replaced 3 of them! Good Luck!

 

[MoparPat]

thanks, just what I needed to know

 

[dgc333]

FWIW, a 4 pin ecu is a direct replacement for a 5 pin. You can't use a 5 pin in a 4 pin circuit though.

 

[cudamark]

Another thing you might want to check. Some motorhomes have the module and ballast mounted on a panel under the dog house. Make sure it has a good ground strap running to it. Some of thoes panels are made of wood and the ground is real important. Let us know what you find.

 

[djwhog]

fwiw, a 4 pin ecu is a direct replacement for a 5 pin. You can't use a 5 pin in a 4 pin circuit though.

ditto

 

[MoparPat]

You are all correct. He found the main body plug to the engine full of corrosion, cleaned it all up and it started right up, he says it actually runs better, Thanks for all your inputs...way cool