GU Headlight Fault

[Crusher_AU]

Hi all

I have an issue on my GU TD42. The L/H headlight will light up both high and low beam when low beams turned on, also the high beam indicator on dash will light dimmely..
When I switch to high beam all ok..

I got a second hand stalk from the wreckers but it didn't fix the problem :( . Could just be bad luck..
Is there picture or diagram showing the pinout for the stalk connector.

Cheers

Mick

[04OFF]

Did you try a new Headlight Bulb ?

[Crusher_AU]

Yes... that was my first try... :( thought it might have been a simple short in the bulb

[04OFF]

So assume you checked the plug connection (3 pin) that goes onto the bulb then, no melting of the plastic etc ? , the other thing that comes to mind is perhaps a back feed from your spottie relay trigger wire (if you dont have em ignore this one, lol)

[Yendor]

Check the earth connection in the L/H headlight plug.

[Crusher_AU]

So assume you checked the plug connection (3 pin) that goes onto the bulb then, no melting of the plastic etc ? , the other thing that comes to mind is perhaps a back feed from your spottie relay trigger wire (if you dont have em ignore this one, lol)

Yes I found the 3 pin connector all burnt and charred, I replaced it thinking that would fix it but no luck... (this was before I replaced the combination switch), when I did a volt check at the plug I get 12 volt on both HB and LB when LB turned on..

I just reviewed the wiring diagrams... HAS TO BE the combination switch.. I think I just lucked out with the one from the wreckers.... will pull it today and check its switching....

It was funny the wreckers in Revesby wants $40 more than Nissan genuine for the combination switch :icon_bonk:.

The spottie relay is on the HB for the RH HB and has been there for many years trouble free...

If the combination fixes this I will upgrade the wiring.

I think I have caused this by running higher watt bulbs than the harness could handle... original lights are so bad in low beam.. Standards are in there now...

[Crusher_AU]

Check the earth connection in the L/H headlight plug.

I will check that today thanks....
I think it should be ok as HB works fine....

Mick

[Yendor]

Yes I found the 3 pin connector all burnt and charred, I replaced it thinking that would fix it but no luck... (this was before I replaced the combination switch), when I did a volt check at the plug I get 12 volt on both HB and LB when LB turned on..

I just reviewed the wiring diagrams... HAS TO BE the combination switch.. I think I just lucked out with the one from the wreckers.... will pull it today and check its switching....

It was funny the wreckers in Revesby wants $40 more than Nissan genuine for the combination switch :icon_bonk:.

The spottie relay is on the HB for the RH HB and has been there for many years trouble free...

If the combination fixes this I will upgrade the wiring.

I think I have caused this by running higher watt bulbs than the harness could handle... original lights are so bad in low beam.. Standards are in there now...

Was this with the plug stilled plugged into the bulb?

If so, try doing a volt check with the plug disconnected.

[Yendor]

I think you may have put the pins in the wrong place when you replaced the plug.

I think you have the Red wire with a Blue trace and the Black wire in the wrong positions.

[Crusher_AU]

No pins are correct.. triple checked...
I am getting power to both the HB and LB pin on the LH headlight only....

Now I have the diagram I am sure it is the combination switch and I just lucked out at the wreckers..

In the diagram the red lightening bolt shows the area of the switch I am sure is shorting to both LB and HB... and as the HB indicator is driven from here makes even more sense as to why when in low beam my HB indicator lights up dimmley.....

[Crusher_AU]

Check the earth connection in the L/H headlight plug.

The more I think about this earth.. You could be right...
I will check this afternoon.. but if the earth was dodgy it could be using the HB as the path of least resistance hence why they both light up but only dim...

[Crusher_AU]

Check the earth connection in the L/H headlight plug.

R/H Headlight Earth pin to ground 0.8 ohms
L/H Headlight Earth pin to ground 14.0 ohms

I think you made a good call, I will run a new Earth wire and see. might even relay the whole system and run higher watt bulbs..


Thanks for the help guys..

Mick