My sister's 2005 Meriva is getting through a lot of bulbs, front and rear. Almost every week, something is going. When they've blown, they've usuall y gone that silvery-black colour, too. Is it going to be the voltage regul ator, which is the only thing I can think of? Is there any way of testing it? Will the voltage present at, say, the battery terminals be higher than usual, which I think is something like 14 volts?
First thing to do is to remove and thoroughly clean the battery terminals. Then do the same for the earth strap(s) where they are bolted to the engine and bodywork.
As you have asked if there is any way of testing, I can assume you don't have access to an accurate multi-meter, but a check of the voltage would be the next step.
Chris
I do have a multimeter which is accurate enough for this, I think. It's a digital one, so it's a bit hard to read if the voltage changes a lot :-) H ow high can the voltage get if the regulator isn't working? I'm assuming i t should never reach, say, 15V, but maybe there's no way it would do that e ven with a broken regulator.
The voltage regulator is a solid state device, and fairly unlikely to allow random, short spikes. It's possible, but doubtful. It's much more likely an intermittent connection is the cause of your problem.
Measure the battery voltage when fully charged, but not running; it should of the order of 12.6v. Compare it to the value you get when running. That will help eliminate any meter inaccuracy; you will be looking at the offset.
As you assume, anything over 15v would be a cause for concern.
FYI, 'posh' multimeters have both an analogue bar display and a peak hold function to help with this sort of fault-finding. Out of the price range of most home mechanics however!
Chris
1st is that if you are using cheap bulbs you cannot expect them to last. The silvery black sounds like you are indeed using boot sale type bulbs.
All you need is a multi meter plugged into the cigar lighter and keep an eye on it. Anything over 14.2V is suspect.
I don't know about the Meriva, but many cars now use more sophisticated charging than formerly. For example, Ford use the unimaginatively-named Smart Charge. When coupled with the correct silver technology battery, 15v will often be seen after a cold start and with a battery that is not fully charged.
Chris
The dashboard lamps on my Puggy flash brighter very briefly when first turned on.
It could be that you are inserting the new bulbs the "wrong" way. I've done this and it seems that it is a "very common mistake". My garage man told me this.
Don't see how you can draw that conclusion. Often seen that in blown bulbs of reputable brand.
Tim
Touching the glass of the lamps can cause premature failure with some types off lamp
When you start the car do so with the lights off feet off the brake peddle, its possible your getting a power surge when you start the vehicle. Check the battery , earth connections, and all the relevant plastic electrical sockets for loose or corroded connections , check the alternator output too under load
The silver/black is deposit from the Tungsten filament self destructing which on a better quality bulb should not happen so easily as the Tungsten is purer.
I think chance has more to do with it. If the breaking filament arcs for a while as it breaks, you get a lots of silver deposits. Still, happy to be proved wrong if you can provide any links to support your suggestion.
Tim
. Almost every week, something is going. When they've blown, they've usua lly gone that silvery-black colour, too. Is it going to be the voltage reg ulator, which is the only thing I can think of? Is there any way of testin g it? Will the voltage present at, say, the battery terminals be higher th an usual, which I think is something like 14 volts?
Okay, thanks all. When she brings it round at the weekend, I'll have a bit more information to work with.
I have one of those little DVMs which plugs into the cigarette lighter socket; sensitive to 0.1 volt but needs calibrating against a good DVM for accuracy. Occasionally very handy for checking suspect battery or alternator faults.
What relevance does the information in that link about household lighting have to the problem the OP has with a motor vehicle?
Chris
Car bulbs: Tungsten filament Home light bulbs: Tungsten filament
Demonstrates what I said about buying cheapo bulbs.
Car bulbs supply voltage 11 to 15vdc Home light bulbs supply voltage 240vac +10% -6%
Car bulbs suffer significant frequent shock loadings. Home light bulbs don't.
Car light bulbs no in-built fuse. Home light bulbs have in-built fuse.
No it doesn't.
The author of that article states, without any source, that cheap bulbs blow more frequently. You have stated, without any source, that cheap bulbs blow more frequently. Although that might be so, where is the proof?
It's hard to accept anything in that article as meaningful; the writer completely misunderstands what causes supply circuit breakers to sometimes trip on lamp failure, and is corrected by 'another user'.
One other point; one can assume that VX didn't fit cheap bulbs in production, so why did a number of them blow in the first place?
Chris
*230vac*
(Curse this 20th Century brain!)
Chris
Irrelevant
Incandescent bulbs? You sure?
You are telling me that a 50p boot sale made-in-Chrina bulb is made to the same standard as a Philips/Osram bulb. I'd lay money on cheap bulbs probably being at the route of the OP's problem.
The proof is in the OPs experience.
A surge from the arcing of a filament going o/c may well knock the ECB out. That is what it is designed to do after all.
You assume the OP had the car from new and no tit has been mucking about fitting after market bulbs.
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