techman1

When you did the install did you disconnect the battery?

deekay911

The non-shifting gearbox is the Tiptronic 'get-you-home' mode for when the battery is almost flat. It happened to me on my 964 tip. Once the battery is charged it will be fine.

IXLR8

They have a good one for under $15. I have this model in my roadside repair kit under the hood of my 993. Get one with a 10A DC setting. This one has that.



Less guessing and more measuring! Besides a battery's health can only be judged by a load and capacity test. The load test is the most important aspect in starting a car.

If more owners installed one of these, they'd know what was wrong on the spot.

zenithblue993

I checked the voltage on my battery 5 min ago, and it said 11.45 Volts. Now here is another problem, I drove it half a mile from my apartment, got pulled over my the cops saying one of my headlights were out.

So then I drove back home, and the car started for some reason to slowely die. I would rev the engine and it would seem to get power just enough to park it. After I parked it, i turned the car off. Then tried to turn it on. I got the CLICKING noise which sounds like the battery.

Could this be a bad alternator, how do i test it?

IXLR8

That is considered a fully discharged battery.

Start the engine, have someone take it to 2000 RPM and measure the battery voltage. What is it and is it increasing slowly?

Roverdoc

This seems as simple as a bad battery. Swap it out.

IXLR8

Well it might be now due to not being fully charged.

Question is, why is it in the state it is in?

Is the alternator charging to ~14.2?

zenithblue993

Hm, it could have been my hids that drained the entire battery or a coincidence. I did drive today 40 miles on highway and everything was fine.

So 11.xx V is not a good enough charge for a battery?

How to i measure the altenator with a multimeter?

Thanks!

IXLR8

Battery voltage gives you a rough idea of state of charge. That is quite dead.


You don't. You measure battery voltage while the engine is running at about 2000 RPM or more.

ble2011

A little off topic, but when I replaced my radio to an aftermarket Panasonic, it shows the voltage in a little box in the corner of the display. I always thought, why do I need to see that? I know now.

JB 911

Very nice! Pic request please. How about while cranking, the engine. Usually the electrics all get turned off don't they to give maximum cranking power? Does the radio and voltmeter turnoff or does the voltmeter stay on?

zenithblue993

UPDATE: So i charged up the battery with a battery charger to 100%. Put it in the car and it read about 12.4 volts, then turned on the car and it was about 13.4 volts. Drove for the next 2 -3 days no problem, then drove on a 200 mile trip. No problem.

Now, about 30 min ago coming home from the door the radio died. Then turned on then things seemed to start to drain. Might I ad i had the head lights on. (HID lights)

The car made it home, measured the battery with the car off and it read 11.4 volts. Then turned the car on and turned on the headlights and the battery read 10.4volts.

So do you think its the battery or the alternator?

AOW162435

- Replace your battery ground strap with a new one from Porsche (~$10 a few years ago from Sunset Porsche).
- Install a fresh battery (I prefer the Interstate MTP-91).
- Report back.



Andreas

techman1

I recall the battery voltage / Alternator output on our cars when running was measured at a little above 14 volts?

I agree the ground strap and battery need replacement, helped on my car.

It sounds like the alternator may be on its way out also.

Roverdoc

Figured this deserves a repost. I too had strange happenings until I swapped out the battery. This seems as simple as a bad battery. Swap it out. Worst case scenario is you get a new battery and do not have to worry about it down the road. Cheap insurance. Good luck.