Headlight Questions - 986 Forum - The Community for Porsche Boxster & Cayman Owners

jpc763 · 06-09-2016, 10:20 AM

All,

I am trying to see if my charging system has issues.

I have the retrofit HID lights that Fred created and have had issues "firing" them in the past. Last night I was driving as twilight came on. I was driving with the radio on and tried to turn on the headlights. The lights did not come on and the dash showed the battery icon. The spoiler raised (at 40 mph) and the radio began studdering. I turnd them off and tried again. No luck. I drove home without the lights but with the dash lights on. I pulled in and hooked my car to the battery tender. It registered 1, then 2 and 3 lights when I left it last night. I got up to 4 lights first thing this morning. Here is the pic.

This morning, it was still at 3 bars until around 8AM when it finally went to full charge.

So my questions are...

1) Is it normal for a battery to be low after a drive?
2) Is this an issue with the battery or the alternator?

Thanks, John

911monty · 06-09-2016, 10:51 AM

Well in general; no it is not normal for battery to be low after a drive, with a working alternator battery should be pretty well charged after about 20 minutes of freeway type driving.

I don't know your battery but the math works like this, 600 CCA battery will take 15hrs to fully charge at the ~ 4amp charge rate your charger has. That's why yours took till 8am.

I'd say you have a bad alternator. A chain auto parts store will usually check for free. Hope this helps.

jpc763 · 06-10-2016, 06:34 PM

Is there a way to check in my garage?

911monty · 06-10-2016, 06:44 PM

Well, Do you have a volt ohm meter? Perhaps the simplest test you can do is, with car off and no charger connected, test the battery voltage. Fresh charged should be ~12 volts. Now start the car and test battery voltage. Have someone rev up to around 3500 rpm. You should see voltage increase to around 13 volts or so. If so alternator is prolly OK.

PS: Make sure lights and all voltage drains are off.

jpc763 · 06-10-2016, 07:22 PM

Well I had a major issue tonight. I was out and tried to turn the headlights on. Nothing. It would flicker but the HID's would not fire. I turned the radio off and still nothing. I drove home with no lights and as soon as I put in in the garage, I plugged it in. 2 lights on the CTEK. It quickly went to 3 and is currently at 4.

So long story short, I cannot do that test right now.

So big question... I have a PCA event tomorrow morning. I will be driving 250 miles RT. The battery will be fully charged tonight, but will it last that long?

Thanks, John

911monty · 06-10-2016, 07:36 PM

Okay. If I have this straight and you had the battery charged but it was dead again today, then you Could have a bad cell in the battery that is drawing the others down, or a continuous drain with the key off.
These are only possibilities since apparently the trickle charger was able to fully charge the battery, meaning drain is less than 4 amps.
Of course all this could have been caused by a bad alternator. Now I said test the fully charged battery, since that was the last known state, but you can do the same test I mentioned. Just use the current battery voltage as base, start car and see if voltage rises.
If you install a new battery you could maybe drive during daytime using no lights 2 hrs each way before low voltage causes problems. However a dead cell or current drain and all bets are off. Of course the starter, radiator and ac fans will all kill the battery.

I wouldn't recommend it. Sorry

jpc763 · 06-10-2016, 08:17 PM

Quote:

Originally Posted by 911monty

Okay. If I have this straight and you had the battery charged but it was dead again today, then you Could have a bad cell in the battery that is drawing the others down, or a continuous drain with the key off.
These are only possibilities since apparently the trickle charger was able to fully charge the battery, meaning drain is less than 4 amps.
Of course all this could have been caused by a bad alternator. Now I said test the fully charged battery, since that was the last known state, but you can do the same test I mentioned. Just use the current battery voltage as base, start car and see if voltage rises.
If you install a new battery you could maybe drive during daytime using no lights 2 hrs each way before low voltage causes problems. However a dead cell or current drain and all bets are off. Of course the starter, radiator and ac fans will all kill the battery.

I wouldn't recommend it. Sorry

Thanks for the info. What about replacing the battery with a new one tomorrow morning?

jb92563 · 06-10-2016, 08:19 PM

If it was me with an event to go to tommorow, I would remove the battery and bring it to the store where they can load test it. If it does not pass you come home with a new battery, if its good then you have a short or fault with something and needs to be debugged before you end up stranded and locked out of the car.

jpc763 · 06-10-2016, 08:23 PM

Quote:

Originally Posted by jb92563

If it was me with an event to go to tommorow, I would remove the battery and bring it to the store where they can load test it. If it does not pass you come home with a new battery, if its good then you have a short or fault with something and needs to be debugged before you end up stranded and locked out of the car.

Thanks! Great suggestion!

The shop opens at 7:30. I can buy a new battery at an auto parts store, right?

I put my car into O'Reilly and it showed me 4 batteries.

John

jpc763 · 06-10-2016, 08:47 PM

I pulled the current battery out. Here it is.

What is the tube coming out of the side in this picture?

Thanks again!

911monty · 06-10-2016, 08:56 PM

That is the vent tube. It vents hydrogen gas from the battery under the car instead of into the closed frunk.

911monty · 06-10-2016, 08:58 PM

Quote:

Originally Posted by jpc763

Thanks for the info. What about replacing the battery with a new one tomorrow morning?

If you can do this then why don't you do as I first suggested and have them test the alternator?????

jpc763 · 06-10-2016, 09:03 PM

Quote:

Originally Posted by 911monty

If you can do this then why don't you do as I first suggested and have them test the alternator?????

So take the car over there in the morning and have them test both things? I removed the battery based on another persons suggestion.

I will reinstall and go to the shop. Hopefully it is just a battery.

911monty · 06-10-2016, 09:06 PM

Quote:

Originally Posted by jpc763

So take the car over there in the morning and have them test both things? I removed the battery based on another persons suggestion.

I will reinstall and go to the shop. Hopefully it is just a battery.

Man I'm sorry. Yes O'reilly's AutoZone etc. can check your battery and alternator, and it's usually free. Good Luck,

Looking at that battery I'm guessing it's around 5 years old and so would be a good candidate for being bad. Don't like seeing the acid around the top plug on a maintenance free battery though.....

jpc763 · 06-11-2016, 05:42 AM

Took car to Autozone (they opened at 7AM). No problem with the battery or the alternator (or starter). Battery was fully charged and passed the load test. Alternator was charging at 13.8 which was a little low, but did not explain my problem.

So good news is that I am going to the track. Bad news is that I need to figure out what is wrong.

Headlight switch?

PLEASE NOTE. I AM STARTING A NEW THREAD, ANSWER THERE.

Gilles · 06-11-2016, 07:15 AM

sorry a duplicate post…

geraintthomas · 06-14-2016, 02:36 AM

This happened to me when I used a HID ballast that wasn't canbus-smart. The battery icon lit up, the spoiler started going absolutely mental and forcing itself closed and open. I switched for a canbus one and it solved it.

Swap your ballasts for canbus ones and you'll be fine.