When should voltage be present at the coil?

1988 DODGE TRUCK
130,000 MILES
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GREG_H_69
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Should I have voltage at the coil as soon as the key is on or only when the motor is cranking/running?
May 29, 2012 at 11:43 PM
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ASEMASTER6371
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as soon as the key is turned on.

what is the issue??

Roy
May 29, 2012 at 11:51 PM
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GREG_H_69
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I don't have voltage going to the coil. The pcm has been replaced with a re-manufactured one.I put one on and when that didn't fix it i thought it was bad and exchanged it for another one. It ran for about 20 minutes then started acting up again.No voltage at the coil. I then unhooked the power from the coil and ran a jumper from the battery. Still won't start.
May 30, 2012 at 11:15 PM
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ASEMASTER6371
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i would look at the ignition switch as the power comes from there not the pcm. if you have your original one, re install it and start from scratch.


Roy
May 31, 2012 at 12:32 AM
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GREG_H_69
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if it would be that,,why won't it start when I run a jumper?
May 31, 2012 at 12:46 AM
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ASEMASTER6371
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because the ignition side feeds more than just the coil.

Roy
May 31, 2012 at 1:54 AM
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GREG_H_69
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i'll try it. thanks
May 31, 2012 at 12:07 PM
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GREG_H_69
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I put a new ignition switch in it. Still doing same thing. It will run sometimes. When it dies and won't start still no power to the coil.
Jun 3, 2012 at 4:19 PM
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ASEMASTER6371
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did you test for power to the coil on the positive side???

Roy
Jun 3, 2012 at 4:25 PM
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GREG_H_69
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yes
Jun 3, 2012 at 4:29 PM
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GREG_H_69
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Guys keep telling me pick-up coil...could this be it?
Jun 5, 2012 at 9:18 PM
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RASMATAZ
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You need to fix the power problem to the coil-the distributor pick-up coil is not gonna operate
Jun 5, 2012 at 11:31 PM
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GREG_H_69
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The pick-up coil sends a signal to the pcm telling it when to send power to the coil and the injectors. I replaced it 2 days ago, runs great now.
Jun 8, 2012 at 10:28 PM
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RASMATAZ
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We know that-The distributor pick-up coil controls the coil and injector-been here before-Your welcome
Jun 8, 2012 at 10:37 PM
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GREG_H_69
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Read what you wrote on June 5.
Jun 9, 2012 at 3:40 PM
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RASMATAZ
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I was giving you a hint-So what's the problem here
Jun 9, 2012 at 4:00 PM
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GREG_H_69
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"You need to fix the power problem to the coil-the distributor pick-up coil is not gonna operate" Looks to me like that answer says the pick-up coil is not the problem.
Jun 9, 2012 at 5:41 PM
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RASMATAZ
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Oh! well you got it fixed-Good Luck
Jun 9, 2012 at 9:18 PM
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