Issues starting after huge screwup...

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Deadeye512xr

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Okay guys, I made a major screw up installing a new motobatt in my 09 vmax and hooked up the battery backwards (I know it was stupid but I was in a hurry and not paying attention) and now I can't get my max to start after replacing the main fuse which blew... I really hope I didn't brick the ecu or some other expensive piece of electronics on the bike. What do I need to look for? I'm used to working on carburetor based bikes so the vmax is a little more advanced than I'm used to with all of the sensors and more complicated circuitry. Is there a way to test the ecu? I have run the diagnostic mode and there were no present codes showing up but I have a check engine light. I do get little puffs of it wanting to fire when I try to start it but it's few and far between. Any help would be appreciated. And please no judgment considering I already about beat my own head against my garage door for making such a stupid and rookie mistake after many years of keeping my bikes running and doing my own repairs.
 
Don't beat yourself up. We all make silly mistakes once in a while

A fellow on another forum worked on his bike and forgot to put the oil back in....then ran it for 15 minutes with no oil. :oops:

I have my moments as well.

Sorry, I don't know anything the electrical system in a Gen 2, but I'm sure someone will be along soon.

Good Luck.
 
Don't beat yourself up. We all make silly mistakes once in a while

A fellow on another forum worked on his bike and forgot to put the oil back in....then ran it for 15 minutes with no oil. :oops:

I have my moments as well.

Sorry, I don't know anything the electrical system in a Gen 2, but I'm sure someone will be along soon.

Good Luck.
Thanks for the kindness my friend. Still kicking myself over this one 🤦‍♂️
 
I hooked up the battery backwards and now I can't get my max to start after replacing the main fuse which blew... I really hope I didn't brick the ecu or some other expensive piece of electronics on the bike. What do I need to look for? I'm used to working on carburetor based bikes so the vmax is a little more advanced than I'm used to with all of the sensors and more complicated circuitry. Is there a way to test the ecu? I have run the diagnostic mode and there were no present codes showing up but I have a check engine light. I do get little puffs of it wanting to fire when I try to start it but it's few and far between. Any help would be appreciated.

It is really motorcycle battery manufacturers that are at fault. How difficult would it be to make tabs/terminals that fit to one side only? With the conical post types, the posts are different diameter so impossible to fit incorrectly.

BTW someone did this on a Gen 1; the main fuse would blow when turning on ignition (or when starter button pressed) - after connecting correctly, it was business as usual.

I see yours in Gen 2 so more electronics and is not bike I am familiar with nor have seen circuit diagram. The fact that the display module still function indicate that some of the electronics can survive a voltage reversal.

It sounds like it is turning over on the starter and is attempting to fire.
I would do the basics:
- look at wiring diagram to find fuses and check there are no other blown fuses (e.g fuel pump fuse)
- check for spark on all cylinders - either pull the leads or more likely coil packs from the spark plugs, insert a spark plug and turn engine over (if you can remove spark plugs, turning over will be easier). When doing this, see if the spark is regular.
- if no spark, you would need to trace the wiring to see if power is switched to the coil packs
- test the crank (and cam sensors) are ok.
- check fuel delivery, ideally you'd want to pull the injectors out but a rough test would be to remove a spark plug and small the fuel or light it
 
It is really motorcycle battery manufacturers that are at fault. How difficult would it be to make tabs/terminals that fit to one side only? With the conical post types, the posts are different diameter so impossible to fit incorrectly.

BTW someone did this on a Gen 1; the main fuse would blow when turning on ignition (or when starter button pressed) - after connecting correctly, it was business as usual.

I see yours in Gen 2 so more electronics and is not bike I am familiar with nor have seen circuit diagram. The fact that the display module still function indicate that some of the electronics can survive a voltage reversal.

It sounds like it is turning over on the starter and is attempting to fire.
I would do the basics:
- look at wiring diagram to find fuses and check there are no other blown fuses (e.g fuel pump fuse)
- check for spark on all cylinders - either pull the leads or more likely coil packs from the spark plugs, insert a spark plug and turn engine over (if you can remove spark plugs, turning over will be easier). When doing this, see if the spark is regular.
- if no spark, you would need to trace the wiring to see if power is switched to the coil packs
- test the crank (and cam sensors) are ok.
- check fuel delivery, ideally you'd want to pull the injectors out but a rough test would be to remove a spark plug and small the fuel or light it
Those are my next steps. Thank you for the reply!
 
My max is back up and running and it ended up blowing the main fuse and the electronic throttle valve fuse in fusebox 2 under the right panel next to the seat. Thank you all so very much for the help and this guy won't be making such a rookie mistake like this one from now on.
 
It was the EVT fuse that was blown along with the main 60 A fuse that I had already replaced. Thank you for the input and help! She's back up and running but I'm going to give my max a good run through to make sure nothing else got damaged.
From now on take great care and time in working on MAX, never be rushed. :)
 
The electronics would be running at 5 v or possibly 3.3v so there would be a voltage regulator. Any clued up engineer would have designed in a diode to protect the circuitry against voltage reversal.... hence why you got away with 0 damage apart from the 2 blown fuses.
 
The electronics would be running at 5 v or possibly 3.3v so there would be a voltage regulator. Any clued up engineer would have designed in a diode to protect the circuitry against voltage reversal.... hence why you got away with 0 damage apart from the 2 blown fuses.
I was worried the ecu had diodes in it that got blown thus completely frying it. I suppose if I had not realized my mistake immediately after touching the ground terminal to the positive side that it would have just continued to blow fuses had the main fuse not blown first but instead it blew second is my guess after the electronic throttle valve fuse... now I just need to do the oil change after I replace my faulty gear shift indicator (was a problem before my mishap) and put in new rear end gear oil as it is 500 miles from it's recommended service.
 

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