Honda Civic headlight problems.

[bradders59]

Firstly, hello everyone. Im new here and hope I am posting in the correct section.

I look after the family cars (four of them) electrics isnt my strong point. Im better with spanners than multimeters.
Recently my sons 2005 Honda Civic has developed a strange issue with its headlights.
When they are switched on,all four bulbs (dipped beam and main beam) come on together, but the main beams are very dim.
Switch to main beam and the drivers side then works as it should but the passenger side bulbs get switched off completely.
I have replaced the switch and tried adding in an auxiliary earth wire in case it was an earthing problem.
Neither of these has had any effect on the problem.
Im hoping some one with auto electrical know how might come up with some further ideas.
Thanks in advance.
Bradd

 

[James]

Could be a faulty relay.

 

[bradders59]

Thanks. There are two relays, one for each light I assume.
I might swap them over and see if the problem changes from one light to the other.
If it does, then I think that would confirm the issue is with one of the relays?

 

[James]

Maybe, it could be one for dipped, one for main.
If they are cheep, I would be tempted to change them both for new and rule out any problem with them.

 

[bradders59]

Hadnt thought of that, thanks. Will have a look at the wiring diagram in Haynes manual.
Then try and source a couple of relays.

 

[Dangerous Brian]

If they are twin filament headlights try the earthing on the passengers side

 

[brianmoooore]

it's almost certainly an earthing problem, as said above, but not necessarily external to the headlamp assembly.

 

[Dangerous Brian]

I should have said passenger side headlight assembly