Left dipped and full beam not working.

[Yurii Chaikovskyi]

Hi,

I got Infiniti Q30, all parts almost the same as from Mercedes A-Class.
Left dipped and full beam stopped working few days ago.
Today tried to change bulb at Halfords and they have told me that bulb just blown out, have you seek for electrician.

I was wondering, is that any steps I can try at home to fix it? I tried to find if the fuse fail or not.
Found a fuse box diagram for W176, it shows that 209 socket for (left lamp unit), but the fuse looks okay.
Are there any relays responsible for headlights?
Are there any other reasons for the light problems caused by electric failure?

As I believe its halogen headlights, if it might help somehow.

Would be thankful for any information.

 

[bembo449]

Is it xenon unit ? Most likely the ballast if it is

 

[Yurii Chaikovskyi]

Is it xenon unit ? Most likely the ballast if it is

How can I check is it xenon or not?
I have tried to look for the whole headlight ok the internet with the serial number Valeo 5DB0A and it shows that unit is halogen.
Also, at Halfords it showed that compatible bulb for is H9 which is halogen.
So can I say that its halogen based on that information?

 

[umblecumbuz]

... or poor earth.

 

[Yurii Chaikovskyi]

... or poor earth.

???

 

[axelcls]

???

Poor, loose black wire (-)connection


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[Yurii Chaikovskyi]

Poor, loose black wire (-)connection


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Thank you for clarifying.
Is that the wire going into the lamp socket?

 

[axelcls]

Not sure, post a picture, please


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[Yurii Chaikovskyi]

Not sure, post a picture, please


Sent from my iPhone using Tapatalk

I mean, I am trying to understand which black wire connection might be loose?

 

[umblecumbuz]

Yurii - if it is a poor ground (earth), there should be a black wire, or more than one, in the lighting circuit.
Find the black wire and trace it to a connection - possibly on the inner wing, but it could be in other places. the black wire is part of the circuit and if the connections are poor, you would get the symptoms you describe. Each connection might need cleaning and remaking.

 

[mattkh]

I mean, I am trying to understand which black wire connection might be loose?

What year is your Infiniti Q30 ??

 

[Yurii Chaikovskyi]

What year is your Infiniti Q30 ??

Its 2016 May

 

[Yurii Chaikovskyi]

Yurii - if it is a poor ground (earth), there should be a black wire, or more than one, in the lighting circuit.
Find the black wire and trace it to a connection - possibly on the inner wing, but it could be in other places. the black wire is part of the circuit and if the connections are poor, you would get the symptoms you describe. Each connection might need cleaning and remaking.

Should I disconnect a battery before any checks?
If so, if negative terminal ( - ) first and then positive ( + ) ?

 

[Yurii Chaikovskyi]

I found a fuse diagram for Infiniti as Mercedes W176 has the same one, fuse for lights are okay, but how can I check for any relay problems?

On the diagram nothing saying clearly (Lights relay) or something, but just as shown on the picture.
Are any of them a part of light circuit?

 

[mattkh]

Did the Halfords staff come out to the car park to look at your Iinfinti Q30 ?
How did you check the fuse ?

 

[sonic]

You need to meter or use a test lamp to establish if there is voltage at the connector. As both beams have failed I would suspect a bad earth, rather than the bulb or power to the bulb. With the bulb out you can meter that as well.

 

[Yurii Chaikovskyi]

Did the Halfords staff come out to the car park to look at your Iinfinti Q30 ?
How did you check the fuse ?

They did all the works inside of their garage.
Open fuse box, checked for any damage, they were okay.

 

[Yurii Chaikovskyi]

You need to meter or use a test lamp to establish if there is voltage at the connector. As both beams have failed I would suspect a bad earth, rather than the bulb or power to the bulb. With the bulb out you can meter that as well.

Should I first start inspecting a black wire and second thing to do is to check if there is a power at the connector?

 

[umblecumbuz]

This 'check for any damage' comment on the fuses can be misleading, depending how the check was carried out.
The common way is to put a meter across the fuse, without disturbing the fuse, which will check the continuity of the fuse itself.

Before now, I have done the same. But after checking each fuse and finding no faults, I have then removed and reinserted each fuse, and fixed the problem. The reason is that the fuse had made a 'dry joint' in its holder, and moving the fuse repaired this joint.

This is probably not your problem, but is worth anyone bearing in mind when checking fuses that have been undisturbed for a long time.

As Sonic says, it sounds like an earthing fault somewhere in the circuit.

 

[Yurii Chaikovskyi]

This 'check for any damage' comment on the fuses can be misleading, depending how the check was carried out.
The common way is to put a meter across the fuse, without disturbing the fuse, which will check the continuity of the fuse itself.

Before now, I have done the same. But after checking each fuse and finding no faults, I have then removed and reinserted each fuse, and fixed the problem. The reason is that the fuse had made a 'dry joint' in its holder, and moving the fuse repaired this joint.

This is probably not your problem, but is worth anyone bearing in mind when checking fuses that have been undisturbed for a long time.

As Sonic says, it sounds like an earthing fault somewhere in the circuit.

I have also found that 12V cigaret port was faulty, just found a burnt fuse in the fuse box, change it and port started working.
I have had a hope that the same might be the case with the lights fuse but it didn't help.

I will try to ask dealer for wiring diagram, it will be a bit easier to understand why dipped and full beam failed at the same time.
I also have a friend who is electrician (but in construction), but maybe he could help me to trace the problem in the wiring.