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CAN Bus Helper Question 2006 R1200RT

06motorradman

New member
I have a 2006 R1200RT with a CAN Bus Helper that I installed beneath the passenger seat years ago. The relay in the helper is activated by the hot lead to the rear accessory socket. I am powering an am/fm/weather radio (JVC), an Autocom unit, and an Autocom Bluetooth adapter module. There are two accessory connections still available on the device. I don't remember who makes the device. It powers all the devices just fine, and always has. I normally keep the bike on a battery tender while it is parked in the garage. My knowledge of electrical systems doesn't go much beyond my train set, or plugging in my electric vest.

Here are my questions:

When the bike is off, long after the relay has switched off, I still have 0.32 V reading at the unused accessory connections. I assume the Helper device is "leaking" a small quantity of voltage past the relay to the accessory terminals. I don't know if any of my connected devices "use" any of this "leaked" voltage when the device is theoretically "off".

Q1: Is this voltage "leak" normal for these CAN Bus Helpers? I never checked it before, so I don't know if this is a recent development.

Q2: Will this "leak" discharge my battery if left disconnected from the battery tender? If so, how long would that take?

Thanks, in advance, for any insight you may have.
 
Voltage should be looked at as the potential amout of force with which electricity could possibly flow. Presence of voltage does not mean that there actually is flow. You need a load or a 'draw'. If there is no draw, there is no flow. If you are worried about battery draw, you neeed to measure the amperage. Amperage is measured (in the case of a small hand held multi meter) by opening the circuit and letting all of the current flow through the meter. For this reason most multi meters are limited in their ability to measure amperage to 10 amps or less. THe thing to watch for when doing this is that when the battery is disconnected then reconnected the can bus will likely "wake up'" and draw a bit more current for a bit until it determines that there are no inputs to process and it will "go to sleep". The at rest state is where you want to measure amperage draw as the "wake up" state is usually 15 or less depending on the programming in the computer(s).
 
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