Jap NC30 Low Beam relay confusion
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Re: Jap NC30 Low Beam relay confusion
Sorry, should have been more specific. On my relay, which contacts are 85, 86, 87, and 30? They aren't marked up and the wiring diagram in the link isn't labeled either.
- thunderace
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Re: Jap NC30 Low Beam relay confusion

The same connections whether you have the 1C or 2NO relay
Conventional wisdom says to know your limits. To know your limits you need to find them first. Finding your limits generally involves getting in over your head and hoping you live long enough to benefit from the experience. That's the fun part.
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Re: Jap NC30 Low Beam relay confusion
Brilliant! Nice one!
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Re: Jap NC30 Low Beam relay confusion
Ok, I've plugged in as above. Whether the low beam switch is on or off I always have continuity between 30 (input) and 87a. So is my relay knackered?
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Re: Jap NC30 Low Beam relay confusion
I'll have one please mate...might as well sort mine out - want to run a 100w rally H4 lamp in my single headlight...thunderace wrote:85 to earth
86 to the switch
87 to the headlights
30 to the battery (via 15A fuse for twin headlights)
Do you still need a relay? I can get one posted out tomorrow.

IMPERATOR REX ANGLORUM
The V4 is the law..
NC30 - No9 - my old mate
The V4 is the law..
NC30 - No9 - my old mate
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Re: Jap NC30 Low Beam relay confusion
Is the rest of your wiring standard to do that?CMSMJ1 wrote:thunderace wrote:want to run a 100w rally H4 lamp in my single headlight...
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Re: Jap NC30 Low Beam relay confusion
spongy.bob wrote:Is the rest of your wiring standard to do that?CMSMJ1 wrote:thunderace wrote:want to run a 100w rally H4 lamp in my single headlight...
No idea! Though I expect with a single lamp the draw will be the same?
Electrics is voodoo...
IMPERATOR REX ANGLORUM
The V4 is the law..
NC30 - No9 - my old mate
The V4 is the law..
NC30 - No9 - my old mate
- thunderace
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Re: Jap NC30 Low Beam relay confusion
If you're using a relay the high current passes direct from battery to headlight through the relay. The wiring should cope fine as the JDM spec bulb has a 55w (or is it 60w?) main beam and all wires are the same spec.
If you've connected as I've drawn, with the switch OFF you should get an open circuit reading (1.) on the multimeter between the battery and headlight connections. With the switch ON the reading should change to a low resistance.
If you've already wired up you can check as follows:
Disconnect the bulb and put your red multimeter probe into the top connector on the plug (56b)

Place the black multimeter probe on the battery negative terminal.
With the ignition and lights OFF you should get a 0v reading.
With the ignition ON and lights OFF you should get a 0v reading.
With the ignition ON and lights ON dipped beam you should get a 12v (approx) reading.
With the ignition ON and main beam lights ON (***not the flasher switch, the proper low or high beam switch) you should get a 0v reading.
***The flasher switch does not switch the low beam off but the high/low beam switch does.
Let me know your results
I thought the relay pins weren't marked?spongy.bob wrote:Ok, I've plugged in as above. Whether the low beam switch is on or off I always have continuity between 30 (input) and 87a. So is my relay knackered?
If you've connected as I've drawn, with the switch OFF you should get an open circuit reading (1.) on the multimeter between the battery and headlight connections. With the switch ON the reading should change to a low resistance.
If you've already wired up you can check as follows:
Disconnect the bulb and put your red multimeter probe into the top connector on the plug (56b)

Place the black multimeter probe on the battery negative terminal.
With the ignition and lights OFF you should get a 0v reading.
With the ignition ON and lights OFF you should get a 0v reading.
With the ignition ON and lights ON dipped beam you should get a 12v (approx) reading.
With the ignition ON and main beam lights ON (***not the flasher switch, the proper low or high beam switch) you should get a 0v reading.
***The flasher switch does not switch the low beam off but the high/low beam switch does.
Let me know your results

Conventional wisdom says to know your limits. To know your limits you need to find them first. Finding your limits generally involves getting in over your head and hoping you live long enough to benefit from the experience. That's the fun part.
- thunderace
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Re: Jap NC30 Low Beam relay confusion
CMSMJ1 wrote:I'll have one please mate...might as well sort mine out - want to run a 100w rally H4 lamp in my single headlight...thunderace wrote:85 to earth
86 to the switch
87 to the headlights
30 to the battery (via 15A fuse for twin headlights)
Do you still need a relay? I can get one posted out tomorrow.
I'll post one out to you Tuesday, no point doing any posting this side of Easter. Still got your address

Conventional wisdom says to know your limits. To know your limits you need to find them first. Finding your limits generally involves getting in over your head and hoping you live long enough to benefit from the experience. That's the fun part.
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Re: Jap NC30 Low Beam relay confusion
Cool - appreciated mate. Also, more electrickery info in this thread as to how it works is good!
IMPERATOR REX ANGLORUM
The V4 is the law..
NC30 - No9 - my old mate
The V4 is the law..
NC30 - No9 - my old mate