Hi,

A few days ago I enabled the Coming Home/Leaving Home option via VCDS on my 2005 Octavia. A few questions come to mind though...

As the headlights (Xenon) stay on for approx 1 minute without the engine running, how much of a power drain is this on the battery?

And what is the wattage (i.e. amount of power used) by the Xenon headlights compared to standard halogens?

If CH/LH is a factory option or standard, do Skoda fit higher-rated battery or make any other adjustments?

CH/LH is a nice feature to have, but I don't want to damage by battery!

Thanks for any help!

P.S. Also enabled auto-locking of doors over 10mph, flashing brake-light under emergency braking, and both rear fog-lights.

I thinks there's also a time setting which can be changed for CH/LH.

Factory fitted Xenons in this Car are rated at 35W, meaning they knock off around 3AH of your Battery for every 1 minute they are ON considering your Battery to be a 72AH. At this rating, it would take nearly 24 mins to deplete the juice of it if left on (when 100% charged). If you crank the engine right after having used this feature once or just a few times and run the Engine long enough for the Battery to recharge itself fully, there should be no problem whatsoever. In other words, under normal circumstances, this will not affect your Battery.

Halogens are usually rated at 50W+ but can vary quiet a lot. I have seen Halogens rated at 170W!

Was wondering if you really need to leave it ON for 1 min? Most I have seen are set to 30 secs, including mine.

Factory fitted Xenons in this Car are rated at 35W, meaning they knock off around 3AH of your Battery for every 1 minute they are ON considering your Battery to be a 72AH. At this rating, it would take nearly 24 mins to deplete the juice of it if left on (when 100% charged).

Your maths is slightly out.

2 x 35W xenons = 70 Watts of power. So the current drain would be 5.8 amps.

In theory that means it would take just over 12 hrs to deplete a 72 ah battery! In real life you conditions you'd get less than 12 hrs out of the battery.....maybe 6 hrs, but way over 24 mins!

The battery on my vRS is a 61aH battery ...Same as a petrol model vRS

Clearly not up to the job

http://www.briskoda.net/forums/topic/258992-is-the-octy-vrs-cr-170-diesel-battery-not-up-to-the-job/

http://www.briskoda.net/forums/topic/262596-what-ah-battery-does-your-fl-octavia-vrs-have/

The fact of the matter is that any repeated electrical load on the battery without the engine running will shorten it's life.

By shorten I mean it could be as little as taking it from 10 winters to it failing in the 9th winter instead.

There are lots of people on here with older Octavia's that have had the CH/LH feature activated for years without noticing any adverse effects on the overall life of the battery.

Me, I'm old school and much prefer the notion of no electrical load before the engine is running and all electrical load off before stopping the engine.

But then I have an outside light shining on my driveway

By the way, the battery spec is not altered to take into account those models with the feature activated.

Does anyone know where the timing option is?

60 seconds is way too long for me but I haven't spotted anything for timing of the lights yet.

Phil

Your maths is slightly out.

2 x 35W xenons = 70 Watts of power. So the current drain would be 5.8 amps.

In theory that means it would take just over 12 hrs to deplete a 72 ah battery! In real life you conditions you'd get less than 12 hrs out of the battery.....maybe 6 hrs, but way over 24 mins!

Thanks for correcting, never considered the other 35W in the pair! It was typo, I actually meant 24 hrs, and by considering the other pair, theoretically it should last for 12 hrs, but in practice this will be much lesser as pointed out by you.

Also the tail lights are on. I wouldn't worry about it. I have mine set to ten seconds but I can set it via maxidot.

Thanks for correcting, never considered the other 35W in the pair! It was typo, I actually meant 24 hrs, and by considering the other pair, theoretically it should last for 12 hrs, but in practice this will be much lesser as pointed out by you.

No problem!

Does anyone know where the timing option is?

60 seconds is way too long for me but I haven't spotted anything for timing of the lights yet.

Phil

if u don't have maxidot, vcds is required.

via maxidot......

mine is setup to use the foglights instead of the low beams (xenons).

i personally don't like the idea of firing the xenons for durations lasting less than a minute.

Edited 22 January, 201313 yr by JR RS

Does anyone know where the timing option is?

60 seconds is way too long for me but I haven't spotted anything for timing of the lights yet.

Phil

IIRC it's in the adaptations not the coding. There are two timings, one for LH and one for CH. The defaults are both usually 30 seconds

I don't have maxidot but do have VCDS.

Also you can't use the fogs as CH/LH lights on a Pre-FL (annoyingly).

Phil

IIRC it's in the adaptations not the coding. There are two timings, one for LH and one for CH. The defaults are both usually 30 seconds

Ah ha!

I hadn't looked in there yet. Will have a play later!

Many Thanks

CH/LH lights won't be a problem for your battery, they're on/off for a very short time every time and in total use far less than the starter+glow plugs on a single start.

Just to correct one point made earlier, though, on startup 35W xenons, especially factory ones, can take in excess of 100W each. This is to get full brightness earlier. It only lasts a few seconds to single tens of seconds at most, though, they gradually go down to 35W.

Thanks for your replies.

It was the potential for shortening the life of the battery I was more concerned about than flattening it, though I understand it doesn't need much of a voltage drop to prevent the car from starting, so I suspect even 1 hour of lights on wouldn't be a good thing, let alone 6! However, less an a minute shouldn't cause any issues.

I found the time-length setting on VCDS, and it was actually set to 80 seconds (more than what I said), so I've reduced it to 30 seconds, which should be plenty.

I looked at mine.

It was set to 30 seconds but was actually staying on longer than that.

Reduced it to 20 and saved. It then stayed on for the same time as before (60 seconds). I went back in and it still said 30. Weird!

Guys... how can you tell if you have a maxidot display or not? i did select it as an option but to be honest, i havent played with it enough to see these other options... at the moment all i have cycled through are the fuel range indicators etc

Thanks, Nige

See here:

http://www.briskoda.net/forums/topic/147872-fl-maxidotnon-maxidot-with-pics/

Cheers buddy :beer:

Edit: Reading that post it sounds like i do have maxidot as i get a picture of the car with the relevant doors open... guess i need to refer to the manual to work out how to work the screen from the stalks... damn Skoda for not making the multi function wheel an option only on the DSG !

Edited 23 January, 201313 yr by Nigel26

As an aside, if you're still on your original battery in an 05 I'd say you're on borrowed time with the battery anyway, especially with the cold weather.