[DavidH]

Forgive if this is in the wrong forum box -- I don't know if this is a "Spider" question about electrical stuff, or an "Electrical" question about a Spider. I'm sticking with the former 'cause everyone here is so smart. So here goes... Tonight, I was going through the process of aiming my headlights -- a job that took about thirty minutes (measuring and marking and such). Of course, the headlights were on the whole time. When I got finished and went to start up the car, it wouldn't turn over. Lights were on but a little dim, the radio worked, the dash lights came on. But the starter wouldn't do a thing. As it happened, I waited another half hour, and the battery recovered enough to make the starter turn just enough to make the car start. I have Hella H4 lights and an Optima red battery. Question -- is it odd that the battery ran down that much in just half an hour with only those headlights on? David

 

[Tifosi]

Depending on how juiced up the battery was beforehand, it's not beyond the realm of possibility.

Certainly those lights are a bit steeper draw too, so that prolly didn't help.

The red top in itself is not really as suited as the yellowtop would be for such things. (running stuff while the engine is not)

 

[Alfajay]

Yea, I wouldn't be too critical of your battery. 30 minutes with the headlights on and the engine off IS a big load to put on a battery. Actually, I'm impressed that it recovered without recharging.

In the future, I'd hook a battery charger to the battery before leaving the lights on for more than a few minutes.

 

[DavidH]

Remember a TV ad years ago for a car battery -- maybe it was Delco? It showed a bunch of cars pulled up on a beach with their headlights illuminating a big party. The party lasted a long time, all lit up by the cars' headlights. One by one, the cars' lights dimmed out. First to go was battery Brand X, followed by brands Y, Z, etc. But the one belonging to Annette and Paul stayed on the whole time and was the hit of the party -- and it was a Delco. Either they didn't have Hella H4's back then, or they really ain't makin batteries like they used to. Or the ad was B.S.

 

[Gubi]

The Optima red top has a reserve capacity of 100 minutes, which means it's supposed to have a useful charge after 100 minutes of a 25 A load. Your two bulbs (60 W each) pulled about 10A total. So yeah, that does seem sort of short.

Might not have been fully charged, might be on it's last legs. Or you tried to start it with the lights on, and the draw dropped the voltage below kick-over.

 

[DavidH]

Tom, It's less than six months old. I could put it on the charger for a couple of hours and see what happens. If I stick a multimeter to it, what should "fully charged" read? And what might "not fully charged" read? Grazie> D.

 

[Gubi]

There's a table of charge vs. voltage here:

Car battery - Wikipedia, the free encyclopedia

This is probably only valid right around 75 F, though.

 

[ghnl]

Or the ad was B.S.

OR?!? - - OR?!?!

 

[DavidH]

OR?!? - - OR?!?!

OK -- AND!!

 

[ddouglas77]

That is why I prefer my HID headlights, only 5.8 amps worth of draw total with more than 50% more light Also, if you were adjusting your headlights to begin with, I'd wonder if you drove your car more than usual with the lights on to know to do so. If this is the case, it may be that your alternator is not keeping up with your current draw, thus putting more demand on your battery (in which I smile, because I'm using a Camaro's 100amp alternator and a generic battery that has yet to die).

 

[DavidH]

That is why I prefer my HID headlights, only 5.8 amps worth of draw total with more than 50% more light Also, if you were adjusting your headlights to begin with, I'd wonder if you drove your car more than usual with the lights on to know to do so. If this is the case, it may be that your alternator is not keeping up with your current draw, thus putting more demand on your battery (in which I smile, because I'm using a Camaro's 100amp alternator and a generic battery that has yet to die).

No, the reason for having to re-aim was that I had rewired the lights in order to install relays, and, in the process had to remove the entire light fixtures. When I put them back, they had to be re-aimed. Truth be told, I hadn't driven it awfully much, lately, at all. D.