V50 Electrics : - Low Beam Bulb Failure - Not Bulb

Japster · Dec 13th, 2017, 20:26

Hello, this is my 1st post so be gentle

I've read a lot of forum posts about the my problem so I guess it's a common fault, I have one low beam headlight out with the above warning.
Changed the bulb, no luck.
Looked for fuses, but soon discovered with the aid of a wiring diagram there are no fuses for the low Beam.

So measured the voltage at the bulb connector on the bad side, 14.7V
Measured at the bulb pins (with lamp slightly pulled out) same 14.7V

Measured the good side with the bulb lit and it's measuring 11.7V so I guess this due the the bulb pulling the voltage down under load.

So why isn't my bulb lighting on the 14.7V side?

Any help appreciated but I suspect it's something to do with the CEM

Cheers Craig

Bendolfc · Dec 14th, 2017, 00:35

Have you checked the working bulb from the other side in it? Sounds like the replacement bulb may be duff if there is voltage there.

BJB · Dec 14th, 2017, 10:52

I take it it's an Halogen bulb ?. If bulb ok, voltage ok, only earth left ! (apart from contact problem that is). Have you checked the Voltage by using the earth connection to it, or body earth ?

Japster · Dec 14th, 2017, 20:05

Quote:

Originally Posted by Bendolfc

Have you checked the working bulb from the other side in it? Sounds like the replacement bulb may be duff if there is voltage there.

Well well, it's surprising how far down the rabbit hole I went and missed the obvious. Plugged the good bulb I took out of the car when I put the new set in and it works!

Duff new bulb, what's the chances of that? I'm so relieved I didn't have to rip the CEM out

Cheers Bendolfc

Dec 13th, 2017, 20:26	#1
Japster Junior Member Last Online: Today 15:43 Join Date: Dec 2017 Location: Blackwood	Low Beam Bulb Failure - Not Bulb Hello, this is my 1st post so be gentle I've read a lot of forum posts about the my problem so I guess it's a common fault, I have one low beam headlight out with the above warning. Changed the bulb, no luck. Looked for fuses, but soon discovered with the aid of a wiring diagram there are no fuses for the low Beam. So measured the voltage at the bulb connector on the bad side, 14.7V Measured at the bulb pins (with lamp slightly pulled out) same 14.7V Measured the good side with the bulb lit and it's measuring 11.7V so I guess this due the the bulb pulling the voltage down under load. So why isn't my bulb lighting on the 14.7V side? Any help appreciated but I suspect it's something to do with the CEM Cheers Craig

Dec 14th, 2017, 00:35	#2
Bendolfc Premier Member Last Online: Today 12:10 Join Date: May 2010 Location: Liverpool	Have you checked the working bulb from the other side in it? Sounds like the replacement bulb may be duff if there is voltage there.

Dec 14th, 2017, 10:52	#3
BJB Member Last Online: Mar 7th, 2024 19:05 Join Date: Oct 2011 Location: Ashley Heath	I take it it's an Halogen bulb ?. If bulb ok, voltage ok, only earth left ! (apart from contact problem that is). Have you checked the Voltage by using the earth connection to it, or body earth ?

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)