92 Dakota 5.2

not getting spark at the coil.

Here is what I get. At the coil connector not plugged into the coil— 12v side Steady 12v while cranking
driver side—flickers on and off with the test light

plug the connector in— 12v side steady 12v cranking
driver side the light doesn’t switch on off

i have tried the used coil and went and bought a new coil both same results.

anyone seen this before With a bad coil?
I can’t see how it would be the pcm if it’s driving the connector fine on its own. But shut it down plugged in. Very odd.

Everything else has checked out fine ckps, cps, asd
its somewhere between pin19 of the pcm and the coil.

 

Got a good connection at the PCM? Lighting up a little bulb really doesn't take that much, firing the coil is a bit more demanding. I've seen the connectors in the plug at the coil spread out, and give a poor connection as well.

 

yes I checked the pcm side at pin 19 and it works as it should until I plug the coil connector in.

poor connection at the coil wouldn’t explain why the on off switch of the coil driver stops working.

as far as the light bulb.. well all it takes is the switching on and off of 12v to fire the coil. Light bulb has nothing to do with it.

 

Load on the circuit has a lot to do with it, but, that is neither here nor there.

Can you fire the coil manually?

 

Also, the fire is so short an incandescent bulb won't show it; your eye may not see it with an LED.

Try a NOID light on the ECM side of the coil to see if it's switching (should flicker out).

Do you also have fuel pressure while cranking? Are any of the injectors firing (again, use a NOID light on an injector to check)? How about the fuel pump (does it run? It's controlled by the same signal as the ASD relay)?

It may be a bad PCM; before I blamed the PCM, I'd disconnect the negative cable at the battery, then disconnect/reconnect the 60 pin connector 3 or 4 times, then reconnect the negative battery cable at the battery and see if it starts and run (this will polish the contacts in case it's just an oxidized contact in the connector / on the PCM).

RwP

 

Yes I plan to Try and fire the coil manually after I get back home this afternoon.

yes everything on the asd circuit is working fine.

Testing the wires on the Coil connector unplugged it works just like it should.

but plugged into the coil it still gives it 12v but the ground side shuts off completely.

Even plugged into the fluke meter it shuts the ground switching side completely off when plugged into the coil but works perfectly unplugged. Weird.