Testing an H3 Bulb

Printed From: the12volt.com
Forum Name: Lights, Neon, LEDs, HIDs
Forum Discription: Under Car Lighting, Strobe Lights, Fog Lights, Headlights, HIDs, DRL, Tail Lights, Brake Lights, Dashboard Lights, WigWag, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=76134
Printed Date: November 04, 2025 at 6:45 AM

Topic: Testing an H3 Bulb

Posted By: slvr-bullet
Subject: Testing an H3 Bulb
Date Posted: April 12, 2006 at 3:47 PM

I purchased some OEM fog lights.

Now I want to test them out first before I install them but I can't get it to work.

I'm using a variable DC power supply and when I hook up the +/- (12v) to either the bulb or the wiring harness connector, the voltage just drops to zero.

The front panel of the power supply goes (+/-) (ground) (+/-)

What am I doing wrong?

Replies:

Posted By: Mad Scientists
Date Posted: April 12, 2006 at 4:17 PM

I'd suspect the power supply can't output what the bulb needs.. what's the rating on the power supply?

Jim

Posted By: slvr-bullet
Date Posted: April 12, 2006 at 4:26 PM

Mad Scientists wrote:

I'd suspect the power supply can't output what the bulb needs.. what's the rating on the power supply?

Jim

input = 120v, 60Hz, 80W
output = 0-15v, 1A max.

The bulb is 12v, 55W

Posted By: slvr-bullet
Date Posted: April 12, 2006 at 5:35 PM

Finaly got it to work.

Hooked it up to one of those booster packs.

Thanks for your help tho ;)

Posted By: ff-mike
Date Posted: April 14, 2006 at 10:35 AM

You can use a multimeter to check the bulbs for continuity, or resistance. They measure around 2-3 ohms.

A 12v 55w lamp uses around 4.5amps of current, that is why your 1a power supply did nothing

Posted By: slvr-bullet
Date Posted: April 14, 2006 at 8:38 PM

Yah, I figured that out after I did I=P/V posted_image

Posted By: skyford
Date Posted: May 10, 2006 at 4:33 AM

Can you show me a photo of your H3 bulbs?
posted_image

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HID-High Intensity Discharge
Xenon Lamp for your cars

Posted By: ff-mike
Date Posted: May 10, 2006 at 9:12 AM

That is not an H3

Posted By: slvr-bullet
Date Posted: May 10, 2006 at 11:50 AM

Yah, that looks more lid a HID bulb.

This is a H3 bulb

posted_image

Posted By: skyford
Date Posted: May 17, 2006 at 12:28 AM

Yes, this is just the bulb, and here is a ballast. Two bulbs and two ballasts are included in one unit conversion kits.

-------------
HID-High Intensity Discharge
Xenon Lamp for your cars

Posted By: slvr-bullet
Date Posted: May 17, 2006 at 7:38 AM

skyford wrote:

Yes, this is just the bulb, and here is a ballast. Two bulbs and two ballasts are included in one unit conversion kits.

And the reason for posting HID bulbs and ballasts is?

Posted By: ff-mike
Date Posted: May 17, 2006 at 10:30 AM

https://lfd.lannonfire.com/forums/12volt/H3_Comparison.png
This is why HID bulbs in a filament (eg halogen, incandescant)lamp is a bad proposition.
#1 The HID light source is on a different axis
#2 The HID light source is curved, not straight

Posted By: slvr-bullet
Date Posted: May 17, 2006 at 10:59 AM

Yes I know that Mike but my topic was/is about testing H3 bulbs, nothing about HID bulbs/ballasts.

But anyway, the problem was solved and I appreciate everyone's help posted_image