headlamp mystery

[yellowjacket]

One low-beam headlamp goes out. Not a big deal, you'd think, just get a new bulb and slap it in. (Not the easiest procedure, but OK.)

The new bulb doesn't work either, though, and Mr. Voltometer says there's juice. Could it be a transformer issue, even if the other low-beam (and other front lights) are functional?

Any tips greatly appreciated. I need to stay as visible as possible in the land of ginormous SUVs.

 

[motco]

Unless you have changed the OEM headlights there is no transformer. It's as likely as anything to be an earthing problem local to the headlight unit. Your meter is +ve probe on the supply, but where is the -ve probe? Not on the bulb holder I suspect.

 

[Dino D]

Checked fuses?
I had this one the rear lights.

 

[t-tony]

Did you try the new bulb across a battery with a piece of wire yet? Not unheard of for new bulbs to be faulty.

Tony.

 

[yellowjacket]

OK, so investigation showed it was a blown fuse. I'm not sure why the voltometer (obvious electrical beginner here) seemed to show voltage when tested. But the light works now, hurrah!

I'm wondering whether this is just a sign of a bigger electrical problem with the car. A year-old battery kept going dead and recently the installer claimed the battery is good, so it must be the alternator or the starter. Is it difficult to test these?

Meanwhile, I got a trickle charger so at least I won't have any surprises leaving the garage.

 

[Sean d]

OK, so investigation showed it was a blown fuse. I'm not sure why the voltometer (obvious electrical beginner here) seemed to show voltage when tested. But the light works now, hurrah!

I'm wondering whether this is just a sign of a bigger electrical problem with the car. A year-old battery kept going dead and recently the installer claimed the battery is good, so it must be the alternator or the starter. Is it difficult to test these?

Meanwhile, I got a trickle charger so at least I won't have any surprises leaving the garage.

Check to see if the boot light is going out when you close the boot lid, put your phone on video and place it in the boot

 

[the Nefyn cat]

Unlikely to be the starter draining the battery, and if you connect your voltmeter to the battery, pos to pos, neg to neg, and start it up , you should get somewhere around 14 volts across the battery. Then turn on the lights, heater fan to full, front and rear fogs, anything else there is to put a steady draw on the system (not indicators, too much flashing) and put the revs up to around 1500 and it should still be up around 13-14 volts. If it ain't, might be time to get someone with more tools than just a voltmeter to check it out.

 

[colb]

Always thought these cars needed a volt meter to monitor the output, after I had an alternator go bad I added one of these that plugs in the cig lighter to monitor voltage https://www.ebay.co.uk/itm/12V-24V-...816952&hash=item5b5ecb8696:g:GdMAAOSwkqxdgfhN
Later I fitted a combine usb socket with voltmeter in one of the spare unused switch positions, good for plugging in Satnav or phones https://www.ebay.co.uk/itm/Socket-1...a=0&pg=2047675&_trksid=p2047675.c100012.m1985
This one needs the switch hole making a touch wider so it slots in, power taken from cig lighter socket rear connections

 

[Oddly Godly]

Always thought these cars needed a volt meter to monitor the output, after I had an alternator go bad I added one of these that plugs in the cig lighter to monitor voltage https://www.ebay.co.uk/itm/12V-24V-...816952&hash=item5b5ecb8696:g:GdMAAOSwkqxdgfhN
Later I fitted a combine usb socket with voltmeter in one of the spare unused switch positions, good for plugging in Satnav or phones https://www.ebay.co.uk/itm/Socket-12V-3-1A-2-for-Lighter-Double-In-Honda-Dual-Port-Car-USB-Charger-Adapter/392400874514?_trkparms=aid=555018&algo=PL.SIM&ao=1&asc=20190212102350&meid=33096aa95a7c4e4b8fb16f97a499a64a&pid=100012&rk=4&rkt=12&sd=323215347412&itm=392400874514&pmt=1&noa=0&pg=2047675&_trksid=p2047675.c100012.m1985
This one needs the switch hole making a touch wider so it slots in, power taken from cig lighter socket rear connections

Seems like a good idea I was thinking of changing the cigarette lighter socket to a usb but I didn't want to loose the ability to plug in my tyre compressor. This looks the best of both worlds.