Temperamental Headlight on R32 GTST

[Strexx]

Hi guys - This is doing my head in and I need some help.  12 months ago I rebuilt my LHS headlight assembly as the glass was broken - all three lamps worked as expected small side orange/projector/main headlight, all good..... fast forward 11 months and that LHS headlight assembly only now has the small side orange light working.  I spent considerable time testing with a multi meter - checking the lamps, was I getting voltage at the sockets.... there was no voltage and lamps tested fine.  I reseated all relays, checked & tested fuses, fiddled with switches (if only a wiggle) and sharp taps! and still nothing!

Got fed up and forgot about it until just now - 2 months later as I had not driven the car since - The car started perfectly - when I turned the headlights on BOTH projector lamps came on - I was surprised, so I turned high beam on and.... the projector turned off but the main headlight never turned on. So I went back to low beam and sadly the projector now refuses to turn on. I've tried every switch configuration and both the LHS projector & headlight will not turn on, only the side orange lights. See table below:

What should be the lighting changes with the switch configurations - As I can tell the dash switch does nothing - what should it do?

Can anyone give me some advice on what the issue with my LHS headlight assembly may be?

How can I test the relays?

What else can I test?

 

 

[GTSBoy]

Dismantle the main headlight switch on the binnacle and clean the contacts.

[Strexx]

@GTSBoy you mean the rotating switch?

 

[GTSBoy]

Yes.

[blind_elk]

By "dash switch", I'm guessing you're referring to the push-button, next to the round switch.

It is for fog lights - in the absence of fog lights, it simply turns on park lights - has no effect on projector / main.

Your left lights are working as designed, the problem with the right is, as GTSBoy suggested, a problem with the contacts in the rotary switch.

[Strexx]

I love this forum - I truly do - Thanks GTS Boy & blind_elk .. my headlights now work perfectly.

Thanks so much

 

 

[GTSBoy]

NP. Happy to help. You put in some effort first!

[Strexx]

Headlight switch is flaky again - was thinking of squirting some type of contact cleaner into it - Would WD40 be suitable or do I need a proper contact cleaner?

 

[GTSBoy]

CO contact cleaner, not WD40. Then if you want to lube it you need some dielectric grease to smear on the contacts to try to help stop them arcing and building carbon.

[niZmO_Man]

I say this in every thread like this: put on H4 relay harness. Don't rely on the standard switch to push through adequate amps for your headlights.

[GTSBoy]

33 minutes ago, niZmO_Man said:

I say this in every thread like this: put on H4 relay harness. Don't rely on the standard switch to push through adequate amps for your headlights.

While I don't disagree (I actually agree completely, except perhaps for most R32s not having H4 globes!) - just adding the relays doesn't actually solve all problems. The original headlight switches are intended to have a certain amount of current flowing through them. This current does what is called "wetting" the contacts. That wetting action is a big enough arc as the contacts make and break to burn off some carbon, basically keeping the contacts clean enough to keep working.

When you remove all that load and get the contacts to just switch a relay, the current being switched is no longer enough to wet the contacts and they can start to build carbon. It can actually be worse/more annoying than the high current too hot scenario that we try to solve with the relays.

The answer is to understand what is happening and deal with it appropriately.

[niZmO_Man]

The projectors have that little splitter thing and it connects to H4 plug (hence my H4 harness suggestion).

I agree with you on fixing the bloody switch contacts, but once I cleaned/bent the pins and bunged in my harness, never had an issue.

My GT-R came with burnt plug (at the switch). I'm guessing previous owners tried running 100W H3/H3C bulbs.

[BK]

That's right, All R32s are an H4 main headlight loom with plug in sub harnesses that split to H3C/H3 or H1/H3. Reflectors are straight H4 with no sub harness.

[Strexx]

Well I think my switch has had it - it remains temperamental sometimes it works some times it does'nt .. Cleaned the contacts with wet n dry, used contact cleaner, applied dielectric grease and bent the pins a little .. I think I'll have to bite the bullet and by one for close to $200.