Topic: Munit Blue Shutdown

[spectre]

Motoscope Pro, Munit Blue & Antgravity Battery - All buttons are motogadget, turn signals, etc.

I went through all checks and motogadget / bike were running well. 
I have ran the bike now over 25 times and each time testing components, battery readouts ,etc and was checking out ok.

Background:
Antigravity Battery on battery tender. (battery started at 13.4 v)

Started and stopped bike two times (after would put the battery tender on – was not at full charge between starts), third time bike was running for 5 min. or so and motoscope pro was showing 11.4v so I revved the engine multiple times and it was not increasing the volts by more then .1, then the bike shutdown completely. No warning with all munit lights flashing.

I could not connect to Bluetooth while in app and bike had zero power at key when switched on.

I have noticed that the difference between motoscope pro and the app volts is always .2 lower in app. When I check the battery it is at the app read out and fairly consistent.

After I reconnected the tender, gave it sometime the munit blue was able to reconnect to the app and power back.

I then disconnected the tender, checked with a multimeter in key off on battery and it was dropping .1 every second or two. Almost aligned with the Bluetooth flash on the munit blue.

Retendered the battery and was back at 13.4v, started the bike and it was maintaining volts (12.5-13.1) and revving would increase volts as it should and settle back to (12.6 / 12.5v range).


So a few questions:
Is battery compromised?
3 start/stops is abrupt but maybe that’s the game with an antigravity battery

Motoscope Pro & Mo.App varies volt readings (is that normal? And at a .2 variance?)

Does Bluetooth typically suck the battery that quickly? .1 every second or two with key off

No warning bike shut down
If this is all battery volt related and was riding and making stops, I would turnoff blue tooth to not get stranded but maybe it should just be off all the time unless I need it.


Any tips would be helpful.
Thanks

[Alan F.]

I would remove the battery, charge it fully, then take it to an Auto Parts store for load testing. It might be charging to normal voltage, but it's current capacity could be crap.

Are you running the Honda ignition keyswitch? These have been known to get dirty...causing resistance...and heat...until they melt and fail. Using a relay is a good idea here. Aftermarket replacements have contacts rated for lower current than the original, some have used them successfully, others like relays.

[spectre]

Good thought on testing load and it is the original honda ignition keyswitch.

[calj737]

These bikes are pretty hard on batteries while “testing” them in the garage. If your AG battery is a lithium, it’s even worse because it does not tolerate draining and replenishing like an AGM/lead acid battery.

Your app is reading voltage from the mUnit as witnessed there. The MotoScope is tied into the harness so it will encounter resistance and variance the mUnit won’t see. The Reg/Rec should be seeing the same voltage the mUnit is so battery charging is more accurate. Ideally these should be within 0.1v of each other.

Get a donor battery for testing (a big AGM one with jumpers to the bike). Or at least disconnect most of the outputs (lights, indicators, etc) once you confirm they are correctly configured so as not to draw power from the battery while testing (headlight is a major draw culprit).

Bluetooth will drain your battery some, but I suspect your experience is due to a damaged battery.

[spectre]

I do have lithium, and can disconnect lights, etc. for testing & get a larger test battery.

So next question with this, when I hit start, electric starter runs, the headlight, motoscope pro & tail light come on which is a hit to the battery. Is there a way around that so the headlight doesn't common until I click it on? Would that help preserve  the battery after testing is over?

[calj737]

Yes. Simply remove the output wire to LIGHT from the mUnit. Same for TAIL. RECONNECT them when you’re done testing.

[spectre]

Sorry, yeah I get that for testing.

I was saying for a standard start procedure if the headlight didn't initially come on since it does hit the battery. After bike starts then click the headlight on. Not sure thats even an option but currently it all comes on together.

[ralt12]

I had some growing pains with a bad battery. I'd do the load test first. My headlight is wired to a pushbutton switch that toggles between high beam and low beam, once you push it to turn the light on. To turn the light off, hold the button.

[calj737]

Sorry, yeah I get that for testing.

I was saying for a standard start procedure if the headlight didn't initially come on since it does hit the battery. After bike starts then click the headlight on. Not sure thats even an option but currently it all comes on together.

I don’t believe there is a menu option to eliminate the headlight from START. With push buttons, you can double press the HI/LO button to extinguish the headlight though. Give that careful consideration from a safety perspective (running without a headlight).

What headlight bulb are you running? Stock is likely a 55w so much above that will require an absolutely perfect charging system with no extra load and resistance, plus a strong and healthy battery.

[spectre]

I couldn't find anything on headlight elimination from on start either.
I have a 55w bulb so I guess it is what it is... Ok, careful battery usage is the plan then.

[calj737]

You’re absolutely pushing the limit of the bikes electrical system with the added BT, Dyna electronic ignition, and a Anti Gravity lithium battery. Is your Reg/Rec lithium-compatible? And the charger/tender?

These bikes don’t really produce excess charge until the RPMs get above 2,500 for a sustained time. So low idle riding, traffic, etc will drain even an AGM/lead acid battery.

Just be as contentious as possible about cleaning the entire wiring harness, switches, connectors etc to remove all corrosion and insure you’re operating at optimum levels.

[Alan F.]

I couldn't find anything on headlight elimination from on start either.
I have a 55w bulb so I guess it is what it is... Ok, careful battery usage is the plan then.

I know it's not in keeping with the whole M-unit thing, but a toggle switch on your headlight ground will shut down hi or lo beam.

[spectre]

Wanted to follow up on this.

The original Honda key switch was leaking and I compromised the battery during testing. After new key switch & battery it holds at 13.3-13.4 v.

Feel like after I solve something…something else pops up.

I have a motoscope pro, if I turn the key, activate the motoscope gauge everything works correctly.

If I start the bike, let it warm up, it has steady voltage but after warmed up voltage become erratic and motoscope turns off then back on and completely flakes out on voltage. I’m working my way through grounds/connections but haven’t found anything.

Anyone run into a reboot motoscope cause?

[calj737]

At idle, your charging system is insufficient, especially with that smaller battery. These bikes really need to be run over 2500 RPMs to produce adequate voltage.

[spectre]

I took your recommendation and used a new larger battery and it did the same thing. Also removed headlight out of munit for testing. It’s Perfect for a minute, idle, rev, volts moving up and down as expected then it starts hunting volts. I have made it through 3/4 of the wiring and will check the rest today.

[Alan F.]

Wanted to follow up on this.

The original Honda key switch was leaking and I compromised the battery during testing. After new key switch & battery it holds at 13.3-13.4 v.

Feel like after I solve something…something else pops up.

I have a motoscope pro, if I turn the key, activate the motoscope gauge everything works correctly.

If I start the bike, let it warm up, it has steady voltage but after warmed up voltage become erratic and motoscope turns off then back on and completely flakes out on voltage. I’m working my way through grounds/connections but haven’t found anything.

Anyone run into a reboot motoscope cause?

Sounds like an undervoltage related shutdown. What's the minimum operating voltage specified?

Perhaps an engineer among us could specify an additional capacitor connected in parallel, or some other measure to help keep input voltage within spec?

[stocky]

Sorry, yeah I get that for testing.

I was saying for a standard start procedure if the headlight didn't initially come on since it does hit the battery. After bike starts then click the headlight on. Not sure thats even an option but currently it all comes on together.

If I'm understanding this correctly and you haven't figured it out, yes there is an option in settings that allows you to simply manually control the headlight without it coming on during start or ignition on.
 
Settings->Light->Manually

[spectre]

Thx, yeah I configured that a month ago.

[spectre]

I had a few minutes to outline the setup via diagram to see if Im missing something that maybe causing the issue Im having with erratic volts.

Im using revivals starter solenoid & fuse kit (30 amp fuse), ricks lithium reg/rec with antigravity battery.
Revival would like me to go to the Aux2-program that for switch on ignition instead of lock and double check all grounds.

[calj737]

Started and stopped bike two times (after would put the battery tender on – was not at full charge between starts), third time bike was running for 5 min. or so and motoscope pro was showing 11.4v so I revved the engine multiple times and it was not increasing the volts by more then .1, then the bike shutdown completely. No warning with all munit lights flashing.

So what did you do to correct this behavior beyond recharging the battery?

I have noticed that the difference between motoscope pro and the app volts is always .2 lower in app. When I check the battery it is at the app read out and fairly consistent.

This is an indication that the gauge is getting a reading from somewhere that is sensing a drop in voltage due to a poor connection. The app reads the mUnit, not the gauge.

Retendered the battery and was back at 13.4v, started the bike and it was maintaining volts (12.5-13.1) and revving would increase volts as it should and settle back to (12.6 / 12.5v range).

12.6 is too low an operating voltage for a Lithium battery. Needs to be at least 13.2, up to ~13.6 under revs. Settling to 12.6 is a state of depleting the charge.

Im using revivals starter solenoid & fuse kit (30 amp fuse), ricks lithium reg/rec with antigravity battery.
Revival would like me to go to the Aux2-program that for switch on ignition instead of lock and double check all grounds.

I submit your issue is between the stator harness and the R/R. Either you have compromised wiring from the stator causing a lack of charge output. or your R/R is getting a false reading on the status of your battery and is therefore insufficiently charging the battery.

I really think you need to do a full test on the R/R and the stator to confirm they are working properly. It is possible that the battery once discharged to 11.4v is beyond recovery.

I like to use this diagram:
https://cdn.shopify.com/s/files/1/1091/5694/files/fault-finding-diagram.pdf?235929069374954073

[scottly]

I had a few minutes to outline the setup via diagram to see if Im missing something that maybe causing the issue Im having with erratic volts.

Im using revivals starter solenoid & fuse kit (30 amp fuse), ricks lithium reg/rec with antigravity battery.
Revival would like me to go to the Aux2-program that for switch on ignition instead of lock and double check all grounds.

The green wire from the field coil and the green wire from the regulator both need to be grounded, not just connected to each other like in that diagram.

[spectre]

calj737 - I will be going through everything, thx for posting the test chart.

Scottly - So are you saying this?

[theDQG]

calj737 - I will be going through everything, thx for posting the test chart.

Scottly - So are you saying this?

Yes, ground to frame.

[theDQG]

I submit your issue is between the stator harness and the R/R. Either you have compromised wiring from the stator causing a lack of charge output. or your R/R is getting a false reading on the status of your battery and is therefore insufficiently charging the battery.

+1

I have the M-unit blue on a few bikes and it's never caused any issues- it is solid state anyway so a fault with it would be extremely rare. It must, however, be running at full charge in order to function properly. I would start with testing output from stator.