CAN-bus and the power socket.

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CycleRob
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CAN-bus and the power socket.

Post by CycleRob »

Riding the bike now means I always wear the Widder electric vest. What I found out is that if the vest is plugged in and turned on before the engine is started there's a good chance the vest will not heat up. This never happens from a cold start because the engine is started before I throw a leg over the seat.. With a still hot engine after a stop I mount the bike, plug in the vest and start it up to leave immediately. Then I realize the vest is NOT working and a slew of angry words accompany manual checks of the switch position, plug in being fully snapped in, and the cord plug connection to the vest. I chalk it up to some hidden electrical connection failure and plan to fix it when I get home. When I do get to test it in the garage with a battery charger, the cord's + and - wires individually on an end-2-end plug test carry a 2 amp short circuit despite wiggling and tugging on the wire it's full length. The cord plugged into the vest shows on the charger ampmeter it's working and I soon feel the heat. The cord/switch/vest test OK and work perfectly while being physically stressed. I am a little stumped.

Some days later, the same no-heat failure after an engine stop happens again but I have one more stop to make before going home. After the stop, the vest power switch is turned off until I start the bike and when I turn it on I see the LED voltmeter respond to the extra load . . . it's working! Then it dawns on me what is causing the vest heat failure. The CAN-bus monitoring the power socket sees the 60 Watt load on the socket as soon as the key on and starter are activated and it thinks there is a weak short in the power socket wiring or socket itself so it cuts off the power to the socket. It all fits now. I take back all those harsh words I thought and muttered about my absolutely marvelous 10+ year old Widder vest.

When I very soon have the body work off to add on the Battery Tender power pigtail I am going to rewire the power socket so it's powered by the home-made key on power system. The advantage gained, besides no longer relying on the CAN-bus system is that the vest will go off immediately as I turn the key off. As it is now, the vest stays on a minute after engine shut off if it's not disconnected or switched off.

Note to all heated clothing users; start the engine before you plug in or turn on your 12V heated garments.
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CAN-bus and the power socket.

Post by CycleRob »

On my 67.4 mile ride today in 54--62degF (12.2--16.7degC) I decided to test this CAN-bus control function again and find a way to defeat it quickly should I inadvertently start the bike with the vest powercord plugged in and turned on. The engine is very warm from the 34 mile trip "there" so I plugged in the vest, it's power switch still turned on, before starting the engine. Sure enough, after over 2 miles, I feel absolutely no vest heat. I tried turning the power cord's switch off for a couple seconds, then back on again while traveling at speed. Still no heat a couple miles later. Then I mimic shutting the bike off and restarting it by first turning off the power cord's switch, then turning off the ignition key at 3,500 RPM in 6th gear then back on again after 1 second. That saves time stopping to do the same thing, without using the starter. After the ignition key goes "on", the gauge needles do their "boot up" full scale sweep and the engine runs immediately. Flipped on the the vest's powercord switch and within 30 seconds I feel the heat!! Problem solved. CAN-bus power socket current monitoring and "loaded" power socket power cut-off confirmed. Hope this helps others from beating up their heated clothing's power cords and switches for a perceived power supply fault that is actually something pretty cool the CAN-bus computer has done. You also know how to get it working quickly without stopping during the daytime.
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Re: CAN-bus and the power socket.

Post by CycleRob »

I found out yesterday on my last ride while idling at a traffic light :-" with the heated grips, vest and brake light "on" that my LED voltmeter was cycling between discharging and charging. At only the idle speed, it seemed to cycle the excessive load on/off/on about once/second indicating that the computer was cycling off/on/off/on my heated vest power to prevent the system voltage from going too low. If the user's chosen high power draw was allowed to do that, it could disrupt the control precision of the EFI and ignition systems. It's a priority matter of what is more important . . . your electric vest/jacket-liner/gloves continue to draw their full power at engine idle speed -or- the engine management's ability to control it's functionally necessary voltage/power requirements. :-k

Another hidden asset of the latest generation CAN-bus systems. If you do something disruptive, thoughtless or even electrically damaging, the bike's thoughtfully configured and programmed computer will not let you do it. [-X =D> :smt023
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Re: CAN-bus and the power socket.

Post by NoRRmad »

Ah. Socialized electrics!
:mrgreen: :mrgreen: :mrgreen: :mrgreen:
#388 '02 R1150R Black: The darkest color.
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