Fried PCM?
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Launching!
Joined: Jul 2005
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Fried PCM? I'm not sure if my PCM, BCM, or both are fried. I made the mistake of running hptuners scanner while the car was not running trying to check the fans. While doing so I went to start the car and the gauges swept and the car wouldn't start and when I pulled the key the door chime was still going off and nothing shut off till I pulled the battery. Brought the battery up to autozone they replaced it and said it was a bad battery. Put the new one in same clicking, charged it up because the optima charger said it was only 75% full. Same thing just clicking. Replaced the starter and now it doesn't even click other than once in a while it gives a half click. Swapped the relays around all of them and no change. Had the starter tested and was told it was good and so was the original one.
I'm kind of at a loss as to what would have caused all this after replacing the starter twice and the battery. Hptuners will no longer connect to scan for codes, I changed the ignition switch thinking maybe it was bad but now when I turn it off the power doesn't cut off even with the door open. Could the switch be bad or out of alignment as well, pcm bricked somehow and causing the no read situation? Or could the bcm have gone bad? Another weird thing is sometimes when I connect the battery up it pops the trunk. Thanks for any assistance.
I'm kind of at a loss as to what would have caused all this after replacing the starter twice and the battery. Hptuners will no longer connect to scan for codes, I changed the ignition switch thinking maybe it was bad but now when I turn it off the power doesn't cut off even with the door open. Could the switch be bad or out of alignment as well, pcm bricked somehow and causing the no read situation? Or could the bcm have gone bad? Another weird thing is sometimes when I connect the battery up it pops the trunk. Thanks for any assistance.
Sounds like a loose ground or something else going on, especially with the trunk popping. Having the scanner connected shouldn't do crap. Was the laptop plugged into the wall outlet at the same time you cranked it?
I guess it's possible but the fans are relay controlled so all that you did was have the coil of a pair of relays energized when cranking....the power is fed to the fans through the relay contacts so it's not directly powered.
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Launching!
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Yesterday when I tried to crank the car nothing would happen it wouldn't even try to prime the fuel pump and it wouldn't shut off when I pulled the key and opened the door. Today I try to crank it and now it primes the fuel pump and shuts off as normal but as I try to crank it I get no clicks but if I hold the key like I'm trying to start it the speedo rises to 100mph? I'm not sure what could even cause that.
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Launching!
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I'm actually getting all kinds of weird gauge movement each time I try to start it. It was consistently doing the speedo but now each gauge is doing something different randomly when I try to start it now. The new battery I had tested twice and was told it was good. Could it be bad?
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Verdad Gallardo I guess that's possible, pretty random though lol since it shoukdnt have anything to do with the fans.
Thread Starter
Launching!
Joined: Jul 2005
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It's weird. I had 2 grounds that were snug I tightened them all the way. I recharged the battery again it was down to like 75%. I could read the pcm with hp tuners again but couldn't get the car to start. I measured the battery it was 12.7v and the starters terminal picked up 12.7. I left the Ignition wire off of the starter and then measured voltage from it on the key on. It is picking up like 12.5. Connect it back to the car and it won't spin. I took the starter off and took the battery out of the car. Wired them together with the jumper cables. And jumped it with a screw driver it spun for half a second. Tried it again and got nothing.
Once the weather clears up I'm going to try it again I bought a wired switch just for jumping the starter and I'll see if it continues this. If so I'm guessing the battery is junk even though it's been tested twice and was said to be good.
Once the weather clears up I'm going to try it again I bought a wired switch just for jumping the starter and I'll see if it continues this. If so I'm guessing the battery is junk even though it's been tested twice and was said to be good.