2005 S60 Passenger Low Beam not working

[drfoster]

I know this topic has been addressed but in all the reading I have done here and elsewhere, none of the scenarios seem to match my issue.

Issue: Low Beam Failure warning, passenger low beam out. All other lights in headlight assembly work.

What I have tried:

Replaced low beam H11 bulb. Removed headlight assembly and tested continuity throughout assembly, good. Tested voltage at wiring harness, good (around 12 volts). When headlight assembly connected no voltage only 1.4 volts at plug. When assembly was out I used a 9 volt battery and tested through the assembly I got 9.3 volts to the plug so there is no loss from wiring harness connector to plug.

Replaced wiring connector for H11 bulb inside assembly. Still nothing.

What am I missing? Why would there be no voltage from vehicle wiring harness through assembly?

I spoke to a dealer service tech and they advised it may need a CEM re-flash to the tune of 300 bucks?

Any thoughts or ideas would be greatly appreciated.

[volvolugnut]

Do not take to dealer tech!
I think you have a wiring short or break somewhere between where you test 12V and the bulb itself. The heat from the bulb can cause wires to fail. Yo might also have a failure in the bulb holder.
Keep looking.
volvolugnut

[SuperHerman]

Agree you have a wiring issue - a short doubtful as the wires would melt - but a break more likely or corroded wiring.

Wiggle the harness, compress the wires with your fingers and see if you get any light.

You may need to splice further back on the wiring - look for a point you see good wire (nothing green).

Also make sure your pins are not corroded - sand them lightly -and make sure they are tight. Wiggling the wire may provide a clue here.

[MDK]

Yep, wires.. they get super hot in there..

[drfoster]

Ok, I'll keep working with the wires..Thanks