1999 S70 T5 replaced headlight bulb still out_SOLVED

Post by **ThinAir** » 13 Mar 2014, 19:06

Hello everyone,

I just replaced my low beam headlight bulb and it still does not work. The other side is fine, as are both high beams. The "broken" bulb does not look blown out in the traditional sense. The filament inside is still intact and not blackened. The only difference between the new and the old bulb are slight brown discolorations at the base of the old bulb that look a bit like an electrical burns. I have read a couple articles on MVS about a wiring harness recall for the headlights. Possibilities? Thoughts?

Thanks,

J

Post by **misha** » 13 Mar 2014, 19:35

Does the tail light on the same side work or it's just the front which doesn't?
Is a "blown bulb",yellow indicator on the dash ON?

Post by **ThinAir** » 13 Mar 2014, 19:50

HI Misha,

Tail lights are good and the yellow "bulb out" light on my dash is lit. The low beam fuse is also good. I will check them all in the morning when the sun comes up as recommended in another thread.

Post by **BEJinFbk** » 13 Mar 2014, 20:50

The correct low beam fuse? There's a fuse for each lamp for a total of 4 headlight fuses.
Low beams are 21 and 22 in the "C" fuse box, located at the base of the windshield.

This list is for a '98, but the headlight fuses should be the same:

98 S-V70 Fuse Locations and Legends.pdf: (678.65 KiB) Downloaded 250 times

Post by **ThinAir** » 13 Mar 2014, 20:57

Thanks for the reply. Yep, I checked 21 and 22 and both are good. Since all the headlights except my left low beam work, I assume the relay is good.

Post by **ThinAir** » 13 Mar 2014, 21:39

Hey BEJ,

I wonder if the overload relay you posted about in another thread may be the problem. It has to be something electrical and not easily identifiable. Keep the ideas coming!

J

Post by **BEJinFbk** » 14 Mar 2014, 00:41

I don't think it's an overload relay. That would affect more stuff.

My next idea would be to pull a meter out and start
checking for voltage when the low beam should be on.
The easiest spot would be the fuses ( in the holder, both ends).
That will direct you to the next test point.
If there's power, move downstream to the headlight connections.
No power? Move back up the circuit towards the relay
( not an overload, but the headlight relay).

Post by **rmmagow** » 14 Mar 2014, 06:45

From your description of brownish appearance I'd start to suspect a bad bulb holder. I'd consider a junk yard trip to cut out a couple of connectors or at least take the existing connector and spray it well with some electrical cleaner. When you put the bulb in, did it blow right away? Any burnt electrical smell?

Post by **misha** » 14 Mar 2014, 10:00

Headlight wiring?

Post by **ThinAir** » 14 Mar 2014, 11:26

Hey guys,

I will look into the bulb holder later today. When I called my mechanic he said that, based of the symptoms, he thought might be a headlight module under the dash...(one for each light). I googled it and could not find anything. Do you think he means a relay? What is under the dash that may influence what I am experiencing?