Reduced engine power dies immediately
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Reduced engine power dies immediately
My 04 Z has sat for a few weeks and when I tried to start it the battery was dead. After putting in another battery the car starts and then dies instantly and shows reduced engine power low fuel and service vehicle soon. Power windows and locks aren't working and the radio doesn't work. When I try to pull the codes it shows no comm on everything. What could be the problem. I took the bcm out and the plastic behind it was damp like it had sweated but the bcm itself was dry. I have the bcm inside in front of a heater now. What could be the problem?
Le Mans Master
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From: Wisconsin
I assume everything was OK before the battery went dead. First thing to do is fully charge the battery. Even new batteries may not be fully charged. A weak battery can cause a lot of problems with these cars.
Drifting
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From: Ga
You may also want to consider a tender for your battery when you are not using.
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The car hasn't been driven because of snow here but the 3 weeks it's been sitting somewhere in the middle of that my dad started it and let it idle for a while and it was fine. And now it was so dead the key fob wouldn't unlock the doors. We took a battery out of another daily driven vehicle ( battery is less than 2 years old) and the same problem is there. I also unplugged the STAR connector with 4 wires and nothing changed. I'm getting no comm even with the other battery that is definately good.
Le Mans Master
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From: Wisconsin
The car hasn't been driven because of snow here but the 3 weeks it's been sitting somewhere in the middle of that my dad started it and let it idle for a while and it was fine. And now it was so dead the key fob wouldn't unlock the doors. We took a battery out of another daily driven vehicle ( battery is less than 2 years old) and the same problem is there. I also unplugged the STAR connector with 4 wires and nothing changed. I'm getting no comm even with the other battery that is definately good.
Last edited by JR-01; Mar 16, 2015 at 12:55 PM.
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Is it safe to assume that you tried to unhook the battery for a few minutes to let everything reset, then hook it back up ?
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No originally the car would start and die instantly. I replaced the battery with one from another car and same thing happened. I took the bcm out and dried it over night and left the battery unhooked. Reinstalled the bcm after drying it and the car runs now but still no radio no power windows or doors and it says rep tcs light is on abs is on and the passenger floor behind the bcm is damp. I've cleaned the grounds under the hood and dried the floor removed the PCM and checked all the wiring and everything is fine with no corrosion. Is it possible the bcm is bad? Also the hvac drain was clean why would there be moisture. Idk what to do for it
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I also have no communication to anything at all when trying to pull codes. And the radio doesn't work. I've removed the STAR connector for the door and seat modules. Nothing changed. No oil and temp gauge is working either
Le Mans Master
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No originally the car would start and die instantly. I replaced the battery with one from another car and same thing happened. I took the bcm out and dried it over night and left the battery unhooked. Reinstalled the bcm after drying it and the car runs now but still no radio no power windows or doors and it says rep tcs light is on abs is on and the passenger floor behind the bcm is damp. I've cleaned the grounds under the hood and dried the floor removed the PCM and checked all the wiring and everything is fine with no corrosion. Is it possible the bcm is bad? Also the hvac drain was clean why would there be moisture. Idk what to do for it
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No the problem wasn't there until the battery died. After it died it started all this. And the PCM is under the battery. All the PCM wires and PCM are fine. No corrosion no cuts no anything. The car was just parked and when I got to it the battery was dead and all this started.
Advanced
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No the problem wasn't there until the battery died. After it died it started all this. And the PCM is under the battery. All the PCM wires and PCM are fine. No corrosion no cuts no anything. The car was just parked and when I got to it the battery was dead and all this started.
Le Mans Master
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No the problem wasn't there until the battery died. After it died it started all this. And the PCM is under the battery. All the PCM wires and PCM are fine. No corrosion no cuts no anything. The car was just parked and when I got to it the battery was dead and all this started.
Le Mans Master
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From: Wisconsin
C5 electronics are very sensitive to low voltage. Since everything was fine before the dead battery issue, battery and battery connections are the first places to start, then work from there.
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I just feel like whatever the issue is caused the dead battery. The car could sit weeks and never have one ounce of an issue and even though it had been started in between it's normal sit time the battery was stone dead and nothing was left on. I literally let the car run today for probably 2 hours and the problem never went away. I'll check battery voltage tomorrow.
Le Mans Master
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From: Wisconsin
I just feel like whatever the issue is caused the dead battery. The car could sit weeks and never have one ounce of an issue and even though it had been started in between it's normal sit time the battery was stone dead and nothing was left on. I literally let the car run today for probably 2 hours and the problem never went away. I'll check battery voltage tomorrow.