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no spark. ecu not pulsing ground.

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Old 07-04-2014 | 12:52 PM
  #16  
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Originally Posted by armymech4
More info on the ecu replacement. It was not flashed to my Vin and miles. Maybe that has something to do with the drivers? Ecu was pulled from same year and model. Ohms check from pin 7 to ground. Is 112k ohms. Way too high
Yes, 112K Ohms is high, and not a good sign.

How about from the Gray wire pin cavity to ground?

That's a straight shot from the PCM to the coil, with no other connectors or splices. Maybe you should check the harness wires for chafing, starting at the coil, and working your way back to the PCM.

Additionally, check each connector for corrosion. Back/dark Gray appearance. Green is bad.

It would be nice to have the PCM flashed to your VIN, but the mileage is programmed in the instrument cluster, not the PCM.
Old 07-04-2014 | 01:45 PM
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I have pulse. But am not getting spark or a voltage drop on backside of coil. Code that is new 340. No cam signal to pcm
Old 07-04-2014 | 01:46 PM
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The 112k ohms was with coil unplugged. when plugged back in I read a pulse
Old 07-04-2014 | 02:20 PM
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Originally Posted by armymech4
I have pulse. But am not getting spark or a voltage drop on backside of coil. Code that is new 340. No cam signal to pcm
Check all wiring from the Camshaft Position Sensor and the coil for chafing.

Indeed, the Camshaft Position Sensor determines at which point the PCM coil driver will pulse the coil.

When taking your readings, wiggle the wire harnesses to see if any change occurs.
Old 07-04-2014 | 02:21 PM
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Originally Posted by armymech4
I have pulse. But am not getting spark or a voltage drop on backside of coil. Code that is new 340. No cam signal to pcm
Please explain. I don't understand what you're saying here.
Old 07-04-2014 | 02:31 PM
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Voltage stays the same on back side of coil even when I now have a pulse. If the ground is suppied i would have a voltage drop of almost to zero. I cleared codes Cleaned grounds and have cam signal to ecu. The codes I'm dealing with now are no bus and TCM failure. P1698 p0700 p1694
Old 07-04-2014 | 02:33 PM
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I have dash function and can read codes. I cannot clear them. Only way to do so is to relearn the ecu. I'm thinking I need this ecu flashed with my Vin.
Old 07-04-2014 | 02:55 PM
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Originally Posted by armymech4
I have dash function and can read codes. I cannot clear them. Only way to do so is to relearn the ecu. I'm thinking I need this ecu flashed with my Vin.
pulse is way to slow as well. Can read it on a volt meter
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