You want to make sure that you bypass the alternator with battery charger otherwise you will not see any differience.

 

do you mean disconnect the alternator? where would I attach the jumper cables?

also, when it happens, would turning off all other electric accessories temporarily solve the problem. conversely, when the psm/ abs is functioning fine, would turning on all other electrical accessories induce the problem?

Thanks

Sameer

 

I just spoke to the Porsche mechanic that worked on my car. He used a load tester to determine the problem, not a battery tester like I thought...sorry about the mis information. He ran the car at idle and turned on the A/C unit causing the condenser and evaporator fans to come on. As the engine warmed up the the front and rear engine fans also came on. He took amperage readings before, during and after when the A/C was turned on and then off. The alternator dropped in output amperate to 63 when all of the systems were running. This caused the engine RPMs to get worse as the 996TT electrical system does not favor the engine over other systems such as the PSM and ABS. Evidently the newer models shut down other systems in keeping the engine running. He said the amperage output should have been twice the amount that showed on the load tester. Sorry for the confusion.

 

TJJ: Thankx....good info. I know there are a lot of guys being troubled by the PSM/ABS issue...there's another thread in here going on about the same issues. Most of the time I turn the car off and back on and it clears...but your info about the alternator is worth remembering. What's the correct Amp output rate when the systems are all running?

 

I'll have to check on Monday with the Porsche mechanic as I don't know what the specifications are for the alternator. When we were talking to another last week he the 63 amp output was half what it should have been with a full load. Perhaps someone else on the board knows?