P1389 Code after new PCM
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From: Port Saint lucie
When I turn the key on it has 12v for 1-2 seconds. Then it drops to zero, then when cranking the engine it holds a constant 12v. I’ll check out the grounds after work.
the correct way to test the tan wires would be:
red lead on in dg/or trace wire and black lead on tan wires in connector one? And crank engine?
the correct way to test the tan wires would be:
red lead on in dg/or trace wire and black lead on tan wires in connector one? And crank engine?
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From: Clayton MI
I begin to suspect that your replacement PCM has an issue. Pull the connector, and make sure the pin hasn't been pushed out of it. Clean it as well. If the PCM still doesn't see voltage there, replace it.
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From: Port Saint lucie
the connector the dg/orange wire leads to which would be the c3 connector? Unplug it from pcm and check it for voltage with key on and when cranking? How do i test the ground wire bolted to pcm? I’ve always been suspicious of it, the mount the pcm bolts to doesn’t feel sturdy
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From: Europe
To check the ground wire resistance, set your multimeter to ohm (Ω) reading. Then connect the black lead to the negative battery terminal, and postive to the actual ground wire ring terminal, not the bolt. Make sure the terminal is clean from paint. You should see something like 0.1-0.5 ohms on multimeter.
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When I turn the key on it has 12v for 1-2 seconds. Then it drops to zero, then when cranking the engine it holds a constant 12v. I’ll check out the grounds after work.
the correct way to test the tan wires would be:
red lead on in dg/or trace wire and black lead on tan wires in connector one? And crank engine?
the correct way to test the tan wires would be:
red lead on in dg/or trace wire and black lead on tan wires in connector one? And crank engine?
Next steps would be to measure resistance as noted above. Disconnect battery, pull the connectors off the PCM and measure resistance from connector 1 pin 31 and 32 to battery ground cable. Also between connector 3 pin 12 and the dg/or wire near the PDC/fusebox.
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From: Clayton MI
With connector 3 unplugged, you won't see any voltage on the 'sense' wire, as the wire that controls the circuit is also in that connector. (hence, no ASD relay supplying power.)
The wires are good up to the PCM. The PCM is bad.
The wires are good up to the PCM. The PCM is bad.
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From: Port Saint lucie
Ok the PCM detects crank and camshaft sensor input. Yes red on dg/or and black lead on tan, then observe while cranking.
Next steps would be to measure resistance as noted above. Disconnect battery, pull the connectors off the PCM and measure resistance from connector 1 pin 31 and 32 to battery ground cable. Also between connector 3 pin 12 and the dg/or wire near the PDC/fusebox.
Next steps would be to measure resistance as noted above. Disconnect battery, pull the connectors off the PCM and measure resistance from connector 1 pin 31 and 32 to battery ground cable. Also between connector 3 pin 12 and the dg/or wire near the PDC/fusebox.
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From: Clayton MI
ok I’ll check this out hopefully tomorrow, appreciate the help everybody. Even though it’s been tough i already learned the basics of it lol. I’ve always been able to take engines apart but basic circuit testing was something I’ve never had to come across
ill do the one last test stated above. I used carcomputerexchange.com for it, and I just read they won’t except returns after five days lol I’m gonna have to find a way out of that
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From: Port Saint lucie