No power to coil, engine turns over.

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JHillWRX

JHillWRX

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Anyone have a link to a troubleshooting wiring? I think it could be the ignition control module. Have a tester need to know how and what pins to test voltage.

74 Dart Sport, 360

Or want to walk me through it?

Car has been sitting for 12 years, replaced battery, then starter, cranks over but no spark.
20161019_213620.jpg


Tested ohms resistance on coil, was alright. Don't think i have power to coil, can i test the positive lead disconnected from the coil? When should it see 6v or 12v?
 
The module doesn't supply power to the coil.
Test both ends of the ballast resistor and see what you have there.
If you have power to that but not out of it to the coil you found your problem.

You should see at least some power on the coil + wire in the start and run position of the key.
Yes you can disconnect it to test if you wish.
 
Cool... there is some sketchy things going on the ballast resistor, a few cut off leads... i will start there.
 
JHillWRX said:
Cool... there is some sketchy things going on the ballast resistor, a few cut off leads... i will start there.
Click to expand...

Can you show us a pic of this sketchiness?
That's where ALL the power to the coil comes from.
 
Guessing it wouldn't hurt to replace it for less than $10...

Distributor was brand new, still looks new on the inside.
 
Distributer runs points with a reluctor... is that the correct ballast resistor or should i have the two post one?
 
Tested with the ignition in run i am getting voltage to the coil, 10.5v the battery has 11.5.

Think i am gonna clean up the grounding cables? any ideas?
 
This is how it's supposed to be wired, but I also see changes and disconnections.
Normally there would be a jumper from the top to bottom connectors on the left side and another wire which is cut off on the top right connector.
The top right one should come out of the harness next to the firewall and somewhat close to 12v in the start position of the key.
This diagram should be the one you need.

Not sure if that ignition box is 4 or 5 pin.
The 5th pin is not used in some boxes.

mopar_5pin_ign.jpg
 
TrailBeast said:
This is how it's supposed to be wired, but I also see changes and disconnections.
Normally there would be a jumper from the top to bottom connectors on the left side and another wire which is cut off on the top right connector.
The top right one should come out of the harness next to the firewall and somewhat close to 12v in the start position of the key.
This diagram should be the one you need.

Not sure if that ignition box is 4 or 5 pin.
The 5th pin is not used in some boxes.

View attachment 1714988052
Click to expand...


Everything looks right... it ran before parked...

I am getting a 10.5 volt reading at the + for the coil when ignition is in run...

Should i be looking at the distributor even though it looks new?

I plan on getting a in line spark tester, all i can do is ground a plug.
 
JHillWRX said:
VR? sorry...
Click to expand...

Voltage regulator, but that only affects the charging system and not the starting.

You really need to test for power to the coil in the start position of the key.
Or even just run a jumper from the coil+ to the battery+ and see if it tries to start like that. (only for a test not permanent)
This will give the coil full uninterrupted power and you should have spark when it's cranked.
 
Last edited:
It has brand new optima red top... brand new starter...

Has fuel at the carb and cranks over like its waiting for a spark to go...
 
Thinking i need a in line spark tester and test coil output to distrubutor...

Although the distributor looks brand new
 
JHillWRX said:
Thinking i need a in line spark tester and test coil output to distrubutor...

Although the distributor looks brand new
Click to expand...

As long as your carb doesn't leak fuel or anything like that you can just lay the coil wire on the intake with the boot holding the wire about 1/4 -1/2 inch up off the metal and crank it to see.

Apparently you can also disconnect the distributor at the pigtail and there should be an exposed metal contact on the harness side that goes to your ignition box.
With the ignition in the run position you should be able to touch that one exposed contact to ground and get one spark from the coil.
 
Yeah... tried grounding a plug with a jumper back to the neg terminal and got no spark after trying to ground on block... intake is aluminum.
 
JHillWRX said:
Yeah... tried grounding a plug with a jumper back to the neg terminal and got no spark after trying to ground on block... intake is aluminum.
Click to expand...

Aluminum is fine since it conducts electricity.
This is the deal.
Normally there are two wires that come out of the harness right below your ballast resistor that supply power to the ignition.
One is powered in the start position of the key, and the other only in the run position of the key.
These wires are usually one blue and one brown.

It looks like the brown is on the ballast already, but I don't see the other one.
The blue (or whatever color it ends up being) is supposed to go to the top right terminal on the ballast.
The top left terminal of the ballast is supposed to have a jumper going from the top terminal to the bottom one.
This temporarily bypasses the low voltage side of the ballast to supply a full 12v to the coil during starting, then when you let go of the key and it returns to the run position the power to the coil then comes from the low voltage side of the ballast so it doesn't overheat the coil.

I altered your picture to show how the ballast is usually wired, and I think where the little arrow is in the picture might be the cut off end of your wire that goes to the top right terminal of the ballast resistor.
On the bottom left of your resistor it looks like the jumper from the top to bottom terminal of the ballast has been cut off.
Unfortunately I don't know what else has been done or changed, but this is the factory style hookup for the ballast.

br.jpg
 
Cool, thanks...

I read somewhere that the wiring is based on the distributor either points or electronic(something)?

Car is a 4spd with points...

Was factory 318, now has 360 block.
 
From the time it ran after me and my father restored it, my mother drove it in the rain a few times and she paid someone else to try to fix it... it looks like he replaced the distributor and possibly the ignition control module, the ignition control may have been replaced earlier, but both look brand new.

He may have hacked up those wires, it ran... but died on a short drive. thats why i was thinking the coil.
 
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