Wiring diagram with munit - REVIEW

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Re: Wiring diagram with munit - REVIEW

27 May 2025 09:28
#912927
I have another challenge as well — the high beam indicator on the speedo. I’ve connected it to the high beam output that goes to the front light. The problem is that it’s always on as long as the light is on. I measured the resistance on the bulb itself, and it’s close to 0 between the low and high beam positive terminals. Any ideas? :)

Maybe I connected wrong terminal to the ground…. Need to check :)
I assume this is an incandescent bulb ? the reason you are getting continuity between the two inputs is they share a common ground - the way a bulb works is that initially it is close to a short circuit, the current flow then causes a heat build up in the filament which generates resistance and makes it glow (this is why bulbs often blow when you first turn them on during the "short circuit phase") when voltage is applied to one of the inputs the path of least resistance is ground so the other filament doesn't illuminate, are you sure it's wired correctly to the Mo-Unit (low beam is fed constantly with the ignition, the high/low switch function working correctly through the Mo-Unit?)

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Re: Wiring diagram with munit - REVIEW

27 May 2025 12:12
#912934
Thnx
The wiring from m-unit is correct, but it looks like I have connected ground to the bulb wrong.
Can that be the problem?

low light is always on and when I switch high beam on the light turn on stronger…

Maybe I can configure the high beam to shutoff low beam….?
1981 KZ650-D4, with 1981 z750L engine (Wiensco 810 big bore).

Project:
www.kzrider.com/forum/11-projects/607213...sr-1981-z750l-engine

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Re: Wiring diagram with munit - REVIEW

27 May 2025 12:22
#912937
I would expect the low beam to switch off when high beam is activated, this is the norm

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Re: Wiring diagram with munit - REVIEW

28 May 2025 11:19 - 28 May 2025 13:40
#912972
I disconnected the bulb today and took some measurements: 
  1. With the high beam not activated:
    – 12V between the low beam wire and ground
    – 0V between the high beam wire and ground
  2. With the high beam activated:
    – 12V between the high beam wire and ground
    – 0V between the low beam wire and ground
  Interestingly, there is always 12V between the low beam and high beam wires, but the polarity changes depending on whether the high beam is activated or not. Could this behavior help explain why the high beam indicator on the speedometer isn’t working correctly? (The speedometer input has high resistance.)
1981 KZ650-D4, with 1981 z750L engine (Wiensco 810 big bore).

Project:
www.kzrider.com/forum/11-projects/607213...sr-1981-z750l-engine
Last edit: 28 May 2025 13:40 by gordone.

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Re: Wiring diagram with munit - REVIEW

28 May 2025 11:49
#912973
I disconnected the bulb today and took some measurements: 
  1. With the high beam not activated:
    – 12V between the high beam wire and ground
    – 0V between the low beam wire and ground
  2. With the high beam activated:
    – 12V between the high beam wire and ground
    – 0V between the low beam wire and ground
  Interestingly, there is always 12V between the low beam and high beam wires, but the polarity changes depending on whether the high beam is activated or not This makes little sense since both "high " and "low" are fed from the Mo-Unit - if the high/low switch is wired correctly this would point to a configuration issue (if I get chance I will look at the moto gadget manual tomorrow) . Could this behavior help explain why the high beam indicator on the speedometer isn’t working correctly? Potentially as the indicator is a LED so polarity sensitive (The speedometer input has high resistance.) That is normal given you are measuring an LED

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Re: Wiring diagram with munit - REVIEW

28 May 2025 13:42
#912976
I wrote wrong on point 1, text is corrected.

When I have the light connected it works with low and high beam easy to see the difference in intencity, but are not sure if both high and low is on the same time for high beam.
1981 KZ650-D4, with 1981 z750L engine (Wiensco 810 big bore).

Project:
www.kzrider.com/forum/11-projects/607213...sr-1981-z750l-engine

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