Headlights.

[leeroy73]

Hi chaps. It's seems I have water inside my headlight my low beam light was intermittent for a while and now has completely stopped working I have removed the plastic under the wheel arch and tested the socket for voltage. (No voltage). Would this be the ballast? Side light and high beam work. Have checked fuses behind fuse box.

 

Does anyone know if the high beam is powered by the ballast? If so then my ballast can't be at fault as I have tried other bulbs in the low beam which still don't work. I do have a HID ballast kit but it's H7 high beam kit. Not low beam. Can I use these ballasts for the low / high. Not being tight. Just if I have a set and it will work I may as well use it rather than buy a OEM ballast.

 

TIA

 

Sent from my SM-G925F using Tapatalk

 

 

[Hodaka]

Gosh, lots of headlight talk in the last 1-2 days!

 

From the sounds of things, I take it you have a pre-facelift? If so, the high beam's powered separately from the low beam, and nope, it's not powered from a ballast. The ballast takes the 12v and ramps it up to very high voltage for the xenon, whereas the high beam will power directly from the 12v.

 

Also before I continue, when you say you checked the socket for voltage, did you mean the bulb socket? If so, I definitely wouldn't recommend you do that due to risk of shock!

 

Anyhow, to me it does indeed sound like a ballast issue. First thing would be to check the voltage at the connector, so I'm afraid it's a bumper & headlight off job as far as I know.

 

Once you've disconnected the headlight in question, take a voltmeter and carefully check the voltage for the xenon at the connector. Might be worth asking a friend to turn it on while you're checking with the voltmeter, so you can be sure you're happy you have the right connections before powering it.

 

This is a pic of the connector on the headlight side on my 2004. You need to check the car side, so it'll be the mirror image (?) of the below. Also note the clip is on the bottom side of the pic.

 

 

If you measure 12v at the connector when your friend powers it on (might be worth asking him to turn it on and off a few times and checking the voltage changes accordingly to ensure you're measuring the right thing), then it's a ballast issue as you've tested the bulb already.

 

If you don't measure 12v there, then the problem is on the car side and I have no idea how to fix!

 

In terms of your HID kit, you could use that if you're comfortable wiring it up. Just a few things off the top of my head you should be aware of:

• Unless it's a reputable brand (and maybe even if it is), your HID kit ballast will take longer than the OEM ballast to warm up
  
• It might be worth checking that the ballast has been potted properly, i.e. is properly waterproof. To be honest, I didn't bother with mine as I was being lazy and I thought I can replace if needed
  
• The OEM ballast sits on the bottom of the headlight and covers up a hole, so even if you use your own ballast you'll need to either keep the OEM ballast there, or seal up the (pretty big) hole.
  
• Related to the above, you'll also need to find a way to feed the wire in
  
• Obviously, the connectors will be all incorrect (H7 instead of D2S, the input wires being spade connectors etc...) so you'll need to sort those
  
• If you do need to add any wires, make sure they're rated to handle the current
  
• The above is under the assumption your ballast is a 35W one
  

Personally if you're not sure, I'd recommend getting a OEM ballast. They seem to be in the £50 - £80 range on eBay, which is better than the possibly hurting yourself!