How many bulbs have you replaced?

[Macduff]

I've now had to replace the following in 36k and less than 4 years on our 2004 A4

Sidelight
2 x tail light
rear indicator

At least with DIS I know immediately when a bulb has gone.

In the 3 and a half years and 54k in our Bora I didn't have a single bulb blow despite doing far more commuting and night time driving.

I've never had a bulb go in any other car during 20 years of driving.

In 7 years with my VFR I've had 3 headlight bulbs go and that's it. My Bandit 1200 had a headlight go and my XJ600 had one tail light.

So, do Audis eat bulbs?

 

[james0808]

Not just Audis,in my old MK4 golf i was changing bulbs almost every week,****** thing.

 

[Nickynibbles]

Only replaced the 2 front indicator bulbs, at different times mind you!

 

[cocain]

on my A4 i was replacing bulbs so often that i lost count.
on the A4 I have replaced 2 headlights bulbs in 2 years and the left indicator bulb twice in the last month

 

[dan_b]

On an 03 plate, replaced just one sidelight bulb in two years. Doesn't seem to high an attrition rate!

 

[duane]

I've had 2 front indicator and 1 rear brake bulbs go on the B6 TDI in the past 5 months. Yet on my B5 S4, i haven't changed a bulb in just over 4 years.....As Macduff said at least the DIS tells what bulb has gone and where.

 

[ScottyP45]

Maybe its vibration? Or a sudden output from the alternator causing the voltage to jump or be higher than it should. (or faulty voltage regulator)

Check the battery voltage when the engine is running and at also at 2000rpm with a test meter on DC volts, should read 13.8 to 14.8 volts MAX (normal is 14.1 to 14.4), any higher will cause any bulbs to fail sooner and lower voltage will only shorten the life of 12v halogens as they dont like either lower or higher volts., (ordinary tungsten brake lights etc don't mind low volts)

Also if you fit halogens or xenons (replacements etc) then dont touch the glass parts with your skin as human sweat puts millions of micro-cracks in the quartz silica glass and causes early life failures.

 

[AndyMac]

More taillight bulbs than I can remember on our B6, while my B5 has only used 2 or 3 in 9 years and 150k miles.

 

[JohnboyC]

Funny u say that.....
On my old E36 BMW it never blew one bulb......have owned my Audi A4 2.5TDi Q Sport Avant for 18 months now and its taken out 4 brake light bulbs......WTF ?

 

[Shades]

Both dipped beam headlight bulbs have had to be replaced, two tail lights (not the dual tail/brake lights) that haven't been replaced yet (too lazy and fortunately the A4 has 4 tail lights so its still legal for now!), and the right front side light went the other day...

My Grandad has had a new Skoda and after only a couple of months a couple of bulbs blew. When talking to the bod at the dealership the guy said most VAG cars have problems with blowing bulbs... I'm inclined to believe him!

 

[ScottyP45]

Like I said, you guys should check the voltage coming to the battery, if its too high because of a faulty voltage regulator in the alternator, it will cook batteries eventually and blow bulbs.

A cheap digital multi meter from a hardware shop is all you need, if its higher than 14.4 volts then the reg is f00ked and thats why its popping bulbs.

 

[tjm69]

In 7 months of owning the Audi, 2 brake lights and a headlight.

 

[Macduff]

Like I said, you guys should check the voltage coming to the battery, if its too high because of a faulty voltage regulator in the alternator, it will cook batteries eventually and blow bulbs.

A cheap digital multi meter from a hardware shop is all you need, if its higher than 14.4 volts then the reg is f00ked and thats why its popping bulbs.

No probs with my battery voltage, all in spec. Doubt it's vibration as I think my bikes have any of my cars beaten for vibration!

I just suspect that VAG have cut costs on bulbs and gone for the cheapest they can get. Our 1999 Bora and our 2001 Lupo had no problems (despite doing far more night driving) but our 2004 A4 has blown plenty. Not sure if VAG would source the parts of if it's down to the individual brands to do their own deals. I expect it's at a VAG level.

 

[ScottyP45]

But surely when you buy new bulbs from a non vag source, they should last then?

If they don't then it can't be the bulbs surely?

The fix is to fit LED replacements with resistors built in for the bulb failure unit and then never change them again

 

[wallacr]

For this A4 that I have had for about 10 months, I've only had to replace two headlight bulbs, one for each side.

Rich

 

[Macduff]

But surely when you buy new bulbs from a non vag source, they should last then?

If they don't then it can't be the bulbs surely?

The fix is to fit LED replacements with resistors built in for the bulb failure unit and then never change them again

I've not had to replace bulbs that I've already changed.

 

[ScottyP45]

I've not had to replace bulbs that I've already changed.

Ah ok. :thumbsup:

I guess vag bulbs are **** then LOL

I'll shut up about the battery voltage now!

 

[ozique]

Well, my A4 always have problem with front left indicator, every 2 to 3 weeks, it stops working, i have had to remove the headlight to loosen the indicator holder and tighten it again, then it works.

 

[quattrojames]

1 Year
0 Bulbs

 

[Macduff]

Ah ok. :thumbsup:

I guess vag bulbs are **** then LOL

I'll shut up about the battery voltage now!

No worries! It was good advice.

 

[Les 51]

2 years & 42k I've replaced both headlights with better bulbs, which have both blown and one brake light

 

[bahnstormer]

On my old B5 Avant I was replacing bulbs all the time! I remember on one occasion I switched my dipped beam on and they both blew together, put my front fogs on (it was pre-face lift so fogs were in headlamp cluster) and one of them blew. So I ended up driving 25 miles home on sidelights and one fog light, which was 'fun'. I was regularly losing bulbs on the dash. I used to get them to bulk change the bulbs for the instrument cluster every time it went for a service as one or more would fail to last out.

I had a mechanic friend of mine look over it but he couldn't find any problems, I also got Ipswich Audi look at likely causes of the problem during one of its services, but they couldn't find anything either. I suspected some sort of spiking but intermittent problems are virtually impossible to trace. I had a voltage meter on the instrument cluster that always ran at around 14, never showed anything strange occurring - probably not sensitive enough.

I sold the B5 2 years ago and bought a W211 E320 CDI. In two years not one bulb blew. Having said that, the general build quality of the car was shocking and just about everything else on the car failed so I was glad to offload that and last month I bought a B6 Cab. Beautiful car, but guess what?

Yep, I've already had to replace a blown rear brake light, so here we go again... LOL!

 

[ScottyP45]

Ok, speaking from a professional point of view, the most common engineering problem with a tungsten filament bulb is cold-start fracture of the filament, as the bulb draws a lot more current for a few nano seconds until the tungsten starts to emit electrons.

One way to stop it in design terms is to run a tiny current through the bulbs constantly (via a resistor), not enough to light them but to warm the filament to just below emission temp, then when full voltage is applied (shorting the resistor out effectively), the bulb doesnt experience current shock from a cold start.

What I think may be happening in the audi is surging or spikes in the voltage, at odd times, say when something else switches off leaving a spike on the wires, probably popping the weakest bulb in the set at the time. A cure would be to fit a cheap electrolytic capacitor across all bulbs or feeds to a set of bulbs, perhaps 470uF 24v+ working voltage, and that would soak up any spikes including cold start shock and you would likely see a huge reduction in bulb replacements.

When the supply to a cap protected bulb goes off, the bulb fades out fast but empties the stored charge in the cap, and on re-lighting, the cap represents a low impedance way less than the bulb until it begins to charge (nano seconds) then as its stored voltage rises the bulb gets a smooth rise to full 12v. Surges would be absorbed by the capacitor the same way as it is used in smoothed dc power supplies.

You could fit a single large value capacitor to the main batt feeds like in big ice installs, they protect mosfet power amps from spikes in the 12v and would work just as well. Not so cheap tho, but still affordable.

Read this article:
http://www.patentstorm.us/patents/5463521/description.html

and then see here:

http://www.nexxia.co.uk/CarInstallaccessories/power_capacitors.htm

 

[cocain]

Err say that again!!!!

 

[ScottyP45]

LOL - got carried away there now I read it again! Electronics design is my job so I got a bit techie, sorry but I reckon adding a huge value capacitor to the cars battery - one of those links sells them - would cure the bulb problem. They can be gotten cheaper than that probably, RS Components or Maplin would likely be much cheaper for the same capacity, i.e. 0.5 Farad or 500,000uF (micro-farads) Power Capacitor - same value just written differently, so you know what to look for.

 

[chris_20]

I have replaced 4 bulbs in a year and a half of owning mine but those have all been voluntarily, i changed the front indicators to get rid of the orange bulbs and changed the main headlights for xenons

 

[Macduff]

I have replaced 4 bulbs in a year and a half of owning mine but those have all been voluntarily, i changed the front indicators to get rid of the orange bulbs and changed the main headlights for xenons

Yes, I changed my high beams to Visionplus when my sidelight went. Changed both sidelights to BlueVision. Already have factory Xenons so hopefully won't have any probs with them.

 

[chris_20]

fingers crossed fella

 

[quattrojames]

I have LED front sidelight bulbs, and I noticed the other night when I was parked facing a large glass window that when I started up (with the lights turned off) they flickered briefly on and off as the car fired - it was barely perceptible and even at night you would never notice unless you were parked facing a reflective surface.

Weird though, if all bulbs get a current surge when you start up it cant do them much good can it?!

 

[chris_20]

i thought LEDS's didnt work in our A4s?

 

[quattrojames]

i thought LEDS's didnt work in our A4s?

How do you mean? As long as the bulb fitment is correct LED bulbs will work in any car won't they?

 

[Macduff]

How do you mean? As long as the bulb fitment is correct LED bulbs will work in any car won't they?

Not sure but I think they have problems in cars fitted with full DIS as it does bulb monitoring. To get them to work they must have a resistor (not sure if in series or parallel) to make DIS think that it's a normal bulb.

 

[ScottyP45]

I have LED front sidelight bulbs, and I noticed the other night when I was parked facing a large glass window that when I started up (with the lights turned off) they flickered briefly on and off as the car fired - it was barely perceptible and even at night you would never notice unless you were parked facing a reflective surface.

Weird though, if all bulbs get a current surge when you start up it cant do them much good can it?!

James, you are right about the surge thing, tho most cars do shut down all systems not required for starting while cranking to ensure maximum current is available to the starter motor etc. Leds are long life as long as they are kept to their voltage range so should last in excess of 30,000 hours, maybe as much as 100,000 hours lifespan, a bulb on the other hand is only rated for 3000 to 8000 hours....

If you fit an led bulb and get a DIS bulb fail warning, the resistor you need is calculated thus: say its a 25W brake light, 25W/12V = 2.08A :: 12V/2.08A = 5.8R (ohms) resistance, so you would solder or otherwise fit a 6R (ohm - can't do an ohm symbol lol) resistor in parallel with the led to simulate the old bulb's resistance.

Some led "bulbs" for cars already have such a resistor built in.

 

[quattrojames]

If you fit an led bulb and get a DIS bulb fail warning, the resistor you need is calculated thus: say its a 25W brake light, 25W/12V = 2.08A :: 12V/2.08A = 5.8R (ohms) resistance, so you would solder or otherwise fit a 6R (ohm - can't do an ohm symbol lol) resistor in parallel with the led to simulate the old bulb's resistance.

Some led "bulbs" for cars already have such a resistor built in.

Thats cleared that up then! Lol!

All i know is mine work ok and I never get a DIS warning. And they look cool