Thread: Fixing error code P0560

Hi All,
Need some expert advise from you guys. I have 1998 Pontiac Grand Prix 3.8L supercharged with 170K kilometers. This car has become a worse nightmare for me. Since March this year it's giving me some electrical trouble which no body is able to understand. Error code P0560 (System voltage malfunction). This is an intermittent problem and my car just stalls and transmission doesn't want to shift the gears. I have to drive in 1 gear only. I changed a couple of alternators in 4 months. Both turned out faulty by overcharging. Changed battery and put the new interstate one. Problem still persists. Can somebody help me in resolving this error. Please help me. Your kind advise will be greatly appreciated. I can't tell you how much trouble i have been going thru both financially and mentally just because of this problem.

so you said your having an overcharging problem? that could only be one thing to my knowledge. and that is the voltage regukator in the alternator. I could be wrong but i dont think it would affect the tranny any. if you said it is random then it would be kind of hard to test. but if the problem is steady you could always test the voltage by placing a volt meter on the positive cable on the back of the alternator.it should read around 14.5 volts.