C5 X7 Left Dipped Beam Not Working

[Tony H]

Hello, I have a 2009 C5 X7 Tourer.

The left dipped beam stopped working yesterday. I pulled the H7 bulb out, it looked OK but changed it any way, did not work. Checked 15A fuse 18 under the bonnet OK. Not sure how to troubleshoot from here?

[GiveMeABreak]

Hi and welcome.

Did you actually test the fuse or try swapping it with F17 for the right-hand dipped beam? Sometimes these can have a hairline crack - so may look ok but as the weather gets colder they contract which is enough to cause problems.

[Tony H]

Did swap them yes.

Is there a relay or something?

[GiveMeABreak]

No relays, just the fuses as you've checked. Maxi fuses 4 and 8 supply power from the battery and are also connected to the BSI.

I would give the engine fusebox a good check over - make sure there is not water ingress that has caused any crud to build up. Double check your headlight bulb and these should always be replaced in pairs. Check the earth (MC11) as shown in the diagram below, as this one supplies the left hand light unit.

[Lenny]

Are you absolutely sure you're checking the correct bulb?
I don't wish to insult anybody's intelligence but you do know that there's two H7 bulbs in a C5X7 headlight? The outer one only comes on when you're steering in that direction (if this is enabled in the control menu).
I wasted a good hour trying to suss out why one of my headlight bulbs wasn't working before realising that it was me being dim rather than my the headlight.

[Paul-R]

Have you checked the new bulb with a 12v supply to make sure it's working and not DOA (it has been known). And while you're at it recheck the suspect bulb.

[Tony H]

Found my multimeter today.

I get 14v accross the connector to the bulb. But the bulb has no continuity so think ive bought a broke bulb!

[white exec]

Not unknown. At least you've found the culprit.