computer battery dies in two rides

[Volfy]

First off, yes, you need to check the open voltage of any new lithium coin battery after you first break it out of the package, and before you install into the meter. Some batts might have sat on shelf for a long time and no longer have full capacity.

Replacing the stock meter with a Voyager GPS unit was one of the first things I did after I got my 300RR. Trail Tech had them on sale over Xmas - $200 shipped for the full kit - so it was a no brainer. Stock meter doesn't even have tach. Anyhow, I ran the 12V+ power lead directly to the starter battery, so the meter is always kept fully charged and never draws from the "back up" 3V lithium. I also installed Battery Tender charge lead on every bike, so I keep the starter batt topped off also.

If you prefer to keep the OEM meter, consider getting a Molex 4-pin connector (.062") and reroute your power to the starter battery.

[Angustoyou]

I'm sorry, I don't follow. How does a 4 pin join into the existing 3 pin on the instruments? Do you mean run a live from the bike battery into it, and move the existing red wire that should be doing the job to the 4th whole, so it's actually redundant when joined to the 3 wires for the instruments? (It's probably clear to everyone else, but not me!) I'd go back to my dealer, but he's 3 hours away, and this is frustrating, but no big deal really. Cheers for your help!

[Volfy]

I'll check when I get home, but I remembered it was a 4-pin Molex connector. IIRC, the 3-pin connector is for the speed sensor.

Since I replaced the OEM meter, The only pin I used on the stock meter connector was to the black wire, which is Ground/Earth.

[Volfy]

My apologies, I did get the connectors mixed up. For my '15 300RR:

Pinout for the mating small 3-pin connector:

Green: 12VDC constant, connected directly to regulator output and to starter batt via the 10A fusible link
White: Speed Sensor, front wheel
Brown: Ground/Earth

Pinout for the mating large 4-pin Molex connector:

Pink: High Beam, headlight
Black: Ground/Earth
Violet: Turn signal, Left
Green: Turn signal, Right

***********************************************

'16 300/250RR meter connectors are completely different because it is a new meter with lights for the oil injection. From what I can tell, pinout for the 3-pin that bring power to the meter:

Red: Connected directly to regulator output, powered (~14VDC) only when engine is running
Black: Ground/Earth
Pink: High Beam, headlight

Beta added a diode bank between the voltage regulator and starter battery, so current can only flow one-way from regulator output to charge the battery, which has now become strictly a starter battery. It does not power anything else. Don't know why they did that. I prefer the '15 and earlier scheme.

Looks like if you want to have constant 12VDC to the meter, you might have to do the same mod I did and run a separate wire directly to the battery 12V+ terminal via a dedicated fuse. It isn't that much work, and I prefer the meter to have its own 1A fuse, instead of going through the same 10A main fuse share with all other circuit loads.

[Angustoyou]

Thanks, that makes sense now. I have a 2016 Xtrainer, so have the 3 pin set up and oil light. With the bike running I can't find any power coming from the red wire at the connector, which is weird because the instruments start up when the stationary bike does. I thought it was getting a pulse when the oil check light does its thing on start up, but disconnecting the plug and jamming the voltmeter into the bike end of the red wire and the other end of the voltmeter onto the frame to earth it shows nothing. I'll have to have another look at the weekend.

[bryanaverill]

More info:
I have 14.5 volts on the red and black wire of the three pin connector when the bike is running. The computer appears to be operational without the internal batter installed but connected to the bike when the bike is running. When operated this way, the LO indicator is on along with all the other normal data and dash backlights but the clock and trip settings are lost when the bike is shut off. It seems like the internal battery is only used to power the computer when the bike is not running and to save the clock and trip set-points.

When riding before, I had a LO indication but no other data on the computer was showing, like it was disconnected from the three pin connector.

At this point, I'm thinking that my three pin connector was not fully seated. That would explain SOME of my problem. Doesn't explain why I got a LO reading but the internal batter voltage was 2.96 though. That is still a mystery.

Can't really ride around here until the snow melts.

[mlstevens]

I have put my own earth wire in and soldered the three wires still nothing then i replaced the battery and now it works. When the engine is not running and push a button the back light only stays on for 5 seconds, With the engine running it starts up and the back light stays on all the time. I need to know if the battery is flat is this what happens. I am hoping it was dodgy connections and now that is more reasonable as my oil warning light doesn't work so i took that connector apart and cleaned it and put it together with a wriggle and now the one on the left comes on for a few seconds. I am now thinking about soldering them too.
Why when the battery is flat the computer doesn't work at all?

[bryanaverill]

The computer on my '16 250RR will turn on when the bike is running without any internal battery. If the bike is not running, it will naturally be off and not turn on (because there is no power). It is normal for the backlight to come on momentarily when running on the internal battery only and stay on continuously with the bike running.

Did that answer your question?

[mlstevens]

Hope it is sorted now i have cut out the block connectors and soldered the wires along with my own earth wire. Now just wait and see how long this battery lasts.

[Angustoyou]

Good luck. My internal battery went again on an enduro at the weekend. I'll have another look this weekend and see if I can check back along the red wire to see where the power ends. A bit awkward as the bike obviously has to be running. Can't do some evening spannering in the closed garage.