Left low beam is not working so I checked around and was advised to check the ballast located at the bottom of the headlight unit. No ballast there! Checked the right headlight, which was working fine. No ballast there either! Do the 2005 headlights not require a ballast and if so, any idea why my left low beam doesn't work? I replaced the fuse and changed the bulb. No joy.

 

What bulbs do you have? Halogen or HID were offered. Halogen (H11 or H7) is an incandescent bulb, and has a filament - no ballast or igniter needed. The bulb connectors typically melt on those. The HID bulbs have no filament - like a fluorescent bulb and need a ballast to make the voltage high enough to make gasses in the bulb illuminate without a filament.

 

Thanks for the info. Apparently, my lights are Halogen (H11 bulb). I have replaced the H11 bulb and all of the low beam fuses I can find. Still no low beam on driver's side. I guess I have to look at the more esoteric solutions. My understanding is there is no low beam relay. If you know otherwise, please let me know. Thank you for the information, I appreciate your valuable response.

 

Make sure the socket that plugs into the bulb is not melted - that's a common failure and if so don't buy the cheapest replacement socket - it will melt again.

If the bulb shorts out the CEM will turn off the power to the bulb and set a code. Like a circuit breaker. Sometimes the only way to restore power is to read and erase the codes in the CEM. (with a compatible scan tool)

 

Thanks for the info re the CEM. I had not thought of that. I have a reader specific to Volvos and Saabs. I will let the forum know if it works out.

 

It was the connector as hoonk said. It was corroded and the neg wire pulled out when I tugged on it. The connector was crumbling but fortunately, there was enough left for me to get the little socket part out and reconnect the wire with a little solder and a glue gun. It passed the bumpy road test in front of my house so I guess it is good for now. I found Volvo connectors on ebay that you can splice onto the existing wires for $6.00 a pair so hopefully this jerry-rig will last until they get here.