ECU Wiring

Ranger

Ranger

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I recently replaced the wiring harness on my ECU because the PO had it jury rigged with aluminum crimp pin connectors.
In doing so I noticed that it was not wired according to the diagram.
The light blue with yellow tracer wire goes directly to the + side of the coil, bypassing the ballast resistor.
The car seems to run just fine, although it is hard starting, but I think that may be choke adjustment or starting procedure (still experimenting to figure it out).
Is there a reason for it being wired this way?
Is it doing any harm?
Should I leave it or change it and why?

ecudia.jpg
 
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Went over to Moparts.org and did some research on using or bypassing the ballast resistor. After much reading I couldn't be more confused. :crazy:
 
I think someone might have bypassed the ballast to gain a little extra fire by eliminating the ballast. I'm not sure of the implications of this series but I think if it were mine I would wire it as recommended just for piece of mind.
 
After studying the FSM wiring schematic and doing some probing with a DVM I am pretty sure that the coil is wired through the ballast resistor as it is supposed to be. My understanding is that if it is not, it won't last long.

As for the ECU, I guess I need to study up on it a bit more for a better understanding of exactly what it does and how it does it. That might help answer my question.
 
Seems like if you wire the ecu to the coil + you will not get full voltage in the run position only the start position. I would fix it the way it should be in you diagram.
 
You lost me when you stated that the ballast was bypassed then said is was not.
 
The ECU is not run through the ballast resistor as stated in post #1.
The COIL is run through the ballast resistor as it should be and as it was wired from the factory.
 
You will cook the coil after awhile without a ballast and it will act just like vapor lock unless you get a coil that states it is good for a full 12 volts.
 
Ranger said:
The ECU is not run through the ballast resistor as stated in post #1.
The COIL is run through the ballast resistor as it should be and as it was wired from the factory.
Click to expand...
I see what you mean. If it were mine I would wire it as directed to eliminate future problems that might occure. (just to be on the safe side)
 
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