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Discussion Starter · #1 ·
I have a radar detector spliced in to an unknown tap (it goes with power to the bike).

I’ve noticed that the detector will shut off at certain RPM ranges, and I suspect it might be the electrical fuse box that the K1200S has, because the detector will shut off and on again seemingly at random. I’m trying to determine if it’s the detector or the bike that’s shutting off. Idk what the best way to do this is.
 

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2009 K1300S, 2017 S1000R & 2021 Vespa Primavera clown paint job
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Humm... fuse box?
 

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Discussion Starter · #4 ·
The K1200S fuse box alternative. The electronic thing.

I think it’s the detector, but I’m trying to narrow it down.
 

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The detector shutting down suggests that under certain conditions, the circuit powering it no longer has enough current to handle the detector. I'd be concerned about what else that circuit is powering. I'd recommend tracing the power source and look for a more stable source.

Typically ignition and fuel injection circuits draw more current at higher RPM. You don't want to be tapped into one of these circuits.
 

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One possibility is its powered by the (wrong) wire from the accessory connection in front of the battery. This connector has 3 wires, live, ground, and a speed pulse wire which on face value appears to be a live feed, but the voltage does change depending on the speed. There shold be a few threads about it.
There you go


(1) Brown = ground
(2) Blue/Green = Speed Pulse
(3) Red/White = 12V

The Blue/Green is a pulse derived from the speedometer pulse and very likely will measure around 12V when the bike is stationary. When the bike is moving this lead will have a pulse whose rate will reflect the speed of the motorcycle (each pulse a specific distance and the pulse rate relative to speed). This connector was first introduced on the 2005 K1200LT. This connector is also on the R1200RT, The K1200S and the K1200R. It is the connector used for the BMW Navigator GPS kit. I suspect the speed pulse is for future use with GPS units that employ dead reckoning like the Garmin 2650.
 

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Discussion Starter · #8 ·
One possibility is its powered by the (wrong) wire from the accessory connection in front of the battery. This connector has 3 wires, live, ground, and a speed pulse wire which on face value appears to be a live feed, but the voltage does change depending on the feed. There shold be a few threads about it.
There you go


(1) Brown = ground
(2) Blue/Green = Speed Pulse
(3) Red/White = 12V

The Blue/Green is a pulse derived from the speedometer pulse and very likely will measure around 12V when the bike is stationary. When the bike is moving this lead will have a pulse whose rate will reflect the speed of the motorcycle (each pulse a specific distance and the pulse rate relative to speed). This connector was first introduced on the 2005 K1200LT. This connector is also on the R1200RT, The K1200S and the K1200R. It is the connector used for the BMW Navigator GPS kit. I suspect the speed pulse is for future use with GPS units that employ dead reckoning like the Garmin 2650.
I need to double check how I wired everything. It’s definitely reading normal voltages (~14v), and it’s not speed dependent but engine RPM dependent where it cuts out (very reliably around 7k). Someone on the RD forum reported exactly this happening,
 

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I have a radar detector spliced in to an unknown tap (it goes with power to the bike).

I’ve noticed that the detector will shut off at certain RPM ranges, and I suspect it might be the electrical fuse box that the K1200S has, because the detector will shut off and on again seemingly at random. I’m trying to determine if it’s the detector or the bike that’s shutting off. Idk what the best way to do this is.
Contact the detector vendor tech support or a forum for that detector.. I use escort Max 360c on 2007 k1200gt. wired directly to battery power port. no issues.
 

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Do you know how to wire a relay? Use the switched source to trip a relay and get power / ground from the battery.

Witnout drawing a picture, and a standard Bosch relay:
  • 85 = ground.
  • 86 = SW 12V.
  • 30 = +12 V from battery.
  • 87 = radar detector’s (+) wire.
 

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I have a radar detector spliced in to an unknown tap (it goes with power to the bike).

I’ve noticed that the detector will shut off at certain RPM ranges, and I suspect it might be the electrical fuse box that the K1200S has, because the detector will shut off and on again seemingly at random. I’m trying to determine if it’s the detector or the bike that’s shutting off. Idk what the best way to do this is.
Try hooking up a volt meter to the plug and taking a ride. See if the voltage goes away or stays constant.
 
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