Cranks, No Start, ignition coil wire always grounded
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From: Clayton MI
You can't turn the engine fast enough by hand to get the PCM to trigger the ASD relay.
Legend
Joined: Feb 2005
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From: Fort Worth, TX
This. You have to put the LED from battery voltage to the ground signal for the coil, and spin the engine on the starter.
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Positive of the led to the B/GY, and the negative to ground
Administrator
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From: Clayton MI
Once again, that is working exactly as it should. The PCM breaks the ground circuit to fire the coil. You have provided an alternate ground path, so, the coil will never fire. (until you turn off the ignition anyway, then it will fire once.....)
Hook one side of your led up to the POSITIVE battery cable, the other end goes to the ground side wire of the coil connector, with the coil UNPLUGGED. You don't really care if the engine starts at this point, you are trying to determine if the PCM is actually trying to control the coil.
Hook one side of your led up to the POSITIVE battery cable, the other end goes to the ground side wire of the coil connector, with the coil UNPLUGGED. You don't really care if the engine starts at this point, you are trying to determine if the PCM is actually trying to control the coil.
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Once again, that is working exactly as it should. The PCM breaks the ground circuit to fire the coil. You have provided an alternate ground path, so, the coil will never fire. (until you turn off the ignition anyway, then it will fire once.....)
Hook one side of your led up to the POSITIVE battery cable, the other end goes to the ground side wire of the coil connector, with the coil UNPLUGGED. You don't really care if the engine starts at this point, you are trying to determine if the PCM is actually trying to control the coil.
Hook one side of your led up to the POSITIVE battery cable, the other end goes to the ground side wire of the coil connector, with the coil UNPLUGGED. You don't really care if the engine starts at this point, you are trying to determine if the PCM is actually trying to control the coil.
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I've replaced both, I was tinkering and have some info here though!
Okay, so i put a paper clip into pin 1 of my crank sensor (Gy/B)
and put my led between that and positive+ battery terminal
I cranked and got great light and pulsations
I probed the end of that wire and was trying to see if I got the same on the other end of the wire, my LED fell so I don't know what happened here, but It suddenly started!
I don't now if this was because i was plugging and unplugging the PCM terminals or if i moved one of the wires so that it made a good connection.
Right now it fires right up, but I don't know what the issue is still.
I probed the end of that wire and was trying to see if I got the same on the other end of the wire, my LED fell so I don't know what happened here, but It suddenly started!
I don't now if this was because i was plugging and unplugging the PCM terminals or if i moved one of the wires so that it made a good connection.
Right now it fires right up, but I don't know what the issue is still.
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Sorry to bombard you, but I also got a new code just now while running it was P0320. Which makes me suspect the aftermarket crank sensor even more.
Legend
Joined: Feb 2005
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From: Fort Worth, TX
OK, so, 1997 3.9 V6, as a reminder.
The flexplate for the V6 is goofy and gives crank sensors hell. I had all kinds of issues with 2 diff store sensors till i got a genuine mopar. But even a sensor that's been at the bottom of the ocean for a year should still fire at least once per rotation.
Did you ohm out each of the 3 wires to the crank sensor, and verify connection at the PCM connector? The ground may not go to PCM, I forget.
Second, do you know if the fuel injectors are firing at all? I'm going to guess not, but if they are, that's another rabbit hole.
The flexplate for the V6 is goofy and gives crank sensors hell. I had all kinds of issues with 2 diff store sensors till i got a genuine mopar. But even a sensor that's been at the bottom of the ocean for a year should still fire at least once per rotation.
Did you ohm out each of the 3 wires to the crank sensor, and verify connection at the PCM connector? The ground may not go to PCM, I forget.
Second, do you know if the fuel injectors are firing at all? I'm going to guess not, but if they are, that's another rabbit hole.