F650/800GS GPS Connector Voltage

Discussion in 'Parallel Universe' started by randman59, May 12, 2011.

  1. randman59

    randman59 Adventurer

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    I decided to put my Zumo 660 on a switched power source. After buying the BMW 3 wire GPS connector ($20.00) I connected it to my GPS and added a 1" voltmeter. Works great, gps turn on with the key, and shuts off about a minute after the key is turned off (its a canbus thing). Only thing is the voltmeter is only reading about 8-9volts, shut off or running. I tested the voltage with my portable voltmeter and got the same readings. Directly off the battery I am getting 12+ volts not running or 13+ volts running.

    Is this normal???????
    #1
  2. AlanI

    AlanI Adventurer

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    The Z660 motorcycle mount output is 5V
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  3. JRWooden

    JRWooden Long timer

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    Weird....
    I use the GPS "tap" to run my on-board volt meter and it is accurate.
    My guess is that when you check it with "just" your voltmeter since you are not putting any real "load" on the circuit that you are getting a false reading due perhaps to interaction with the canbus or something.

    The output is supposed to be 12V so do NOT wire it directly to a GPS that is expecting 5 volts :wink:

    Try this to get a better reading:

    Temporarily hook up a small low wattage (turn signal or dome light) 12V bulb from the output to ground then measure the voltage or if you have one handy maybe a 100 - 200 ohm resistor. Either would draw enough power to get an accurate reading.

    You are going between the Red/White wire (+12) to Brown (Ground) and not useing the Blue/Green "speed pluse" wire right?
    #3
  4. randman59

    randman59 Adventurer

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    Yes, I believe I am using the correct wires, not the speed pulse wire. The GPS was previously hooked directly to the battery and worked fine, with the exception of having to manually turn it on/off. There is a voltage reduce dropping it down to 5v for the gps input. I believe the Garmin 660 takes voltages between 10-36v which is why I am concerned about seeing 8-9v on the meter. Good suggestion about running a 12v bulb, I will try that tonight. Thanks
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  5. JRWooden

    JRWooden Long timer

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    rm59:

    I initially had my Garmin GPS wired into the GPS port via a 12V - 5V adapter. (I also have a battery voltage monitor wired to the port).
    The voltage monitor worked fine by it's self, always shutting down after the 1 minute delay. The GPS part also worked fine, when it was connected, but I found that at least with the 12v-5v adapter I was using (Garmin's) that the adapter was apparently confusing the CANBUS and sometimes the port would not shut off after the 1 minute timeout like it was supposed to do when the GPS was NOT connected ... since I don't have the GPS installed unless I'm on a road trip I ended up just wiring the 5-12 converter directly to the battery...

    Your mileage may vary...
    #5
  6. Lounge

    Lounge Been here awhile

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    I use a quick connector that is attached directly to the battery and plug the 660 mount directly to that. Of course, I manually have to shut it off but 12V to the mount doesn't seem to be a problem.

    I would assume that the mount controls the feed voltage to the unit as with many other devices that plug into a 12v "cigarette" adapter or similarly, when you plug your computer into the wall, the transformer converts 110vAC to a usable format for the device. I wouldn't worry too much about your readings.
    #6