Dim Scout headlights

[scandalxk]

Hi All,

 

I've just bought a 2007 Octavia Scout.  It has xenon dipped beams and halogen main beams.  The xenon dipped beams are fine: bright and clear with a crisp-edged dip pattern.  The halogen main beams are pretty dire:  orange rather than bright white, leaving the dip beam pattern clearly visible in the dull puddle of main beam light.  Driving home along Wensleydale last night, the main beams rarely reached the next corner.  (The alignment appears fine.)

 

My previous car was a 2006 Octavia (not Scout).  It had halogen dips and mains.  They were both fine, and I never had a problem with visibility at night.

 

I've bought new replacement halogen (H1) main beam bulbs from the local main dealer: no difference at all.  So I bought some so-called "xenon gas" bulbs from a car accessory shop, which claim to be 120% brighter.  There is perhaps a marginal improvement, but not enough.

 

So, has anyone any view on why the new car main beams are so much worse than the previous (apparently similar) lights - and what I might do about it?

 

Thanks All.

[RainbowFire]

A good pair of halogens (Nightbreakers for example) will help (Or have a play with LED)

 

What you suffer from is a direct comparison: in one go you are comparing HID and halogen (side-by-side/overlap) Gives you an idea of how good HID is compared to halogen, which in turn was better than the awfully shhhocking, barely better than candles that we had before.

 

I've just gone LED on my E36....main beam is hugely improved over what it was. The possible problem you'd have with LED is the CANBus might not recognise the unit, as it draws less power than a halogen, so you may need to investigate a couple of resistors in there.

 

[Longship]

If the main beams are so dim, the first thing I'd check would be the volts they're getting when on.

[brad1.8T]

I've got aftermarket HIDs in my Octy and can confirm that the OEM high beams suddenly become useless once HIDS are fitted.  They are nice extra fill but they don't throw down the road well.

 

Longship has a point.  It's worth covering the basics before buying more bulbs.

[ryan-re]

I tried LED in my main beam and it was no better than halogen due to the beam pattern being awful.

 

When you say you bought some from a motorfactor, were they branded? I personaly wold never buy anything other than the likes of philips etc. I use Philips xtreme vision halogens in my main beam and they are fine.

 

You wont get white light using halogen. The way to get close to white is to coat it in a blue coating. More blue, whiter it will look BUT also the lower the light output will be as it blocks part of the light spectrum.

[scandalxk]

On 06/11/2017 at 21:03, Longship said:

If the main beams are so dim, the first thing I'd check would be the volts they're getting when on.

Ok, thanks. I've got a multimeter, but little idea of how to use it. Presumably I remove a bulb, set the MM to measure volts, stick one probe into the push fitting at the end of the wiring and the other onto the bulb collar seating on the headlight unit, and switch on the main beam??? (Sorry about the stupid question, but I'd rather appear clueless than blow the wiring on my car...!)

[scandalxk]

On 06/11/2017 at 20:45, RainbowFire said:

A good pair of halogens (Nightbreakers for example) will help (Or have a play with LED)

 

What you suffer from is a direct comparison: in one go you are comparing HID and halogen (side-by-side/overlap) Gives you an idea of how good HID is compared to halogen, which in turn was better than the awfully shhhocking, barely better than candles that we had before.

 

I've just gone LED on my E36....main beam is hugely improved over what it was. The possible problem you'd have with LED is the CANBus might not recognise the unit, as it draws less power than a halogen, so you may need to investigate a couple of resistors in there.

 

I understand what you mean, but I honestly don't think it is just a comparison problem. I really can't see as far down the road as I should be able to (and could with my previous car).

Edited 8 November, 2017 by scandalxk

[Longship]

The way I would measure would be to pull out the bulb, just enough to get my multimeter Vdc probes safely touching the two contacts. Switch engine and lights on, and then measure the volts. Bearing in mind the lamps get extremely hot quickly, and you dont want to be touching the glass, hot or cold. If my probe tips weren't insulated up to the last 2mm, I'd wrap a couple of layers of insulating tape around them, just to make sure I didn't short out anything.

 

Stay clear of the high voltage Xenons though!!

Edited 8 November, 2017 by Longship

[paddypaws]

15 hours ago, scandalxk said:

Ok, thanks. I've got a multimeter, but little idea of how to use it. Presumably I remove a bulb, set the MM to measure volts, stick one probe into the push fitting at the end of the wiring and the other onto the bulb collar seating on the headlight unit, and switch on the main beam??? (Sorry about the stupid question, but I'd rather appear clueless than blow the wiring on my car...!)

You need to measure the voltage with the bulb IN and ON.  You need to measure that the bulb is receiving 12v on load. The bulb draws current so if there's resistance in the wiring then some voltage will be dropped across the  problem part of the wiring. If you measure voltage with the bulb out any resistance in the wiring will be insignificant compared to the several megaohms of the meter and it will not be a  useful reading.

 

Make sure the meter is set to measure D.C. voltage before connecting it up across the bulb terminals. If you have it in the wrong mode e.g. current you will get a bang blow fuses in the car or the meter.

[scandalxk]

2 hours ago, paddypaws said:

You need to measure the voltage with the bulb IN and ON...

Make sure the meter is set to measure D.C. voltage...

 

Yep, thanks, will do.

Edited 9 November, 2017 by scandalxk

[scandalxk]

So the voltage at the bulb is about 11.3V, which I assume is OK.  (Thanks for advice on how to measure.)  The lights are dim with the original H1 bulbs and with the identical, brand new replacements from the local main dealer, and almost equally dim (very little difference, if any) with the supposedly "120% brighter" replacements I bought from an accessories shop.  They are called Ring Automotive Xenon Ultima.  Am I right in thinking that the word "xenon" in that name is actually slightly misleading?  They behave nothing like the actual xenon dipped beams (for example they don't flash briefly on switching on, and the light they emit is orange rather than blue-white, as stated.)

 

Perhaps I need to just try and get used to it.  I am 99% sure that the main beams on this car are not as bright as the similar lights on my previous Octavia, and I don't think it is just comparison with the bright white xenon dipped beams on this car.

 

Thanks for the responses.

 

scandalxk

[Breezy_Pete]

11.3 sounds low to me; system voltage with engine running should be over 14V.  You won't  get all of that at the bulb holder but I think it should be more than you're seeing. Lamp brightness is roughly proportional to the square of applied voltage, so this could well be your problem. Measure what you're getting across the battery terminals with engine running.

 

[scandalxk]

Ah - engine was not running. Give me a few minutes!

[Longship]

Measure lamp voltage and battery voltage with engine running, both should be over 13v.

[scandalxk]

So with the engine running: 11.8V at the bulb, 14.4V at the battery terminals.

[Longship]

I don't know whether this car has a main beam relay. If so, I'd look at swapping that and seeing if it improves.

 

I know the later versions can have the voltage set in the body control module. Maybe the volts have been set low?

Edited 9 November, 2017 by Longship

[Breezy_Pete]

Good at the battery, still low at the bulb. Will have a look at a wiring diagram in a bit.

[skomaz]

6 minutes ago, scandalxk said:

So with the engine running: 11.8V at the bulb, 14.4V at the battery terminals.

 

thats your issue then...   low voltage at the bulb.  problem now is how to trace that back and work out where its losing voltage.

 

daft question but i cant remember if the main beams are on a separate fuse...   might be worth checking and having a quick look at it to see if its has tarnished contacs...

[Breezy_Pete]

Sorry, can't spot anything much from looking at wiring diagram. Main beam bulbs fed directly from BCM, no indication that there's a relay in there, no obvious dedicated fuses.

Hopefully someone else knows or can figure out more than me about it. It would be good if someone with a similar car could do a comparison measurement.

[Longship]

I know on my '11 there is a option via Carista to set the voltage 12.3-13.6 or direct battery. Maybe OP's car has had voltage set low to suit the Xenons?

[scandalxk]

There's no dedicated fuse for the main beams on my car. There are two 30A fuses, one each for the right lighting system and the left lighting system. There is no sign of any corrosion or dirt on the fuses.

 

What and where is the BCM? Is that the body control module? How is it adjusted - via a PC connection? Sounds like not something for an amateur. What is Carista?

[Longship]

Carista is an App that allows you to access fault codes, customise settings etc. It is very user friendly. I bought the Carista bluetooth OBD dongle (£30) and installed the app on a android phone. Costs another sum for a years or weeks pro access, but you can check settings for free.