P500 Shifting and battery issues

[AM500]

I have a 2016 500.
Was having battery overheating issues and bought a new voltage rectifier and battery.
That seemed to work for a while and here recently I discovered I have a short somewhere and can’t locate it. I installed a master switch but something is still draining my battery.
And also started having shifting problems. Won’t upshift from L to 2 or 3 unless I come to a complete stop.Then if I’m in R and try to go back to N I have to kill and then restart it to make it work.

And last night my battery overheated again and was smoking and leaking.
Really starting to get frustrated with this thing.
Could all these problems be related?

 

[Dave75]

Think about installing a voltmeter, if you do not have one. That way when you have shifting problems, you can see what voltage you are at.

 

[Keebler]

I am a shade tree mechanic and it sounds like you have no choice except to start troubleshooting the electrical system. You are going to need a multi meter for checking voltage and current. Measure the voltage across the battery with the engine off and you should get between 12 and 12.5 volts. Start the P500 and measuring the voltage across the battery, it should increase by between .5 to 1 volt. If this is the case then the charging system is probably Ok. Next disconnect negative cable from the battery and set your multi meter to current then measure between the negative battery terminal and the negative battery cable, the current should not be over a couple milliamps (Note: Do not try to start the P500 or even turn on the key with the multi meter connected between the negative cable and negative battery terminal). If the current is more than a couple milliamps, then start pulling fuses until you isolate the circuit with the current drain. If you find a circuit with a current draw you will need to troubleshoot differently depending on which circuit it is, in all cases check for bare wires and dirty connectors. If you have any electrical add-ons like winch, light bar, stereo, etc. I would suspect them first. Hope this helps, I am a bit perplexed by the battery overheating, that sounds like either a major load that I would expect to blow a fuse, or an alternator that is not regulated.

 

[Mudder]

Had to replace my voltage regulator on my 2017 P500. Spiking at 18 volts and it damaged (overheat swelled) the battery and would not hold a charge. New battery, and installed a dash voltmeter to monitor and no issues since. Had to send back a non OEM regulator, OEM one was the way to go.

 

[AM500]

I will give it a

I am a shade tree mechanic and it sounds like you have no choice except to start troubleshooting the electrical system. You are going to need a multi meter for checking voltage and current. Measure the voltage across the battery with the engine off and you should get between 12 and 12.5 volts. Start the P500 and measuring the voltage across the battery, it should increase by between .5 to 1 volt. If this is the case then the charging system is probably Ok. Next disconnect negative cable from the battery and set your multi meter to current then measure between the negative battery terminal and the negative battery cable, the current should not be over a couple milliamps (Note: Do not try to start the P500 or even turn on the key with the multi meter connected between the negative cable and negative battery terminal). If the current is more than a couple milliamps, then start pulling fuses until you isolate the circuit with the current drain. If you find a circuit with a current draw you will need to troubleshoot differently depending on which circuit it is, in all cases check for bare wires and dirty connectors. If you have any electrical add-ons like winch, light bar, stereo, etc. I would suspect them first. Hope this helps, I am a bit perplexed by the battery overheating, that sounds like either a major load that I would expect to blow a fuse, or an alternator that is not regulated.

I’ll give it a try with my multi meter tomorrow.

 

[AM500]

Had to replace my voltage regulator on my 2017 P500. Spiking at 18 volts and it damaged (overheat swelled) the battery and would not hold a charge. New battery, and installed a dash voltmeter to monitor and no issues since. Had to send back a non OEM regulator, OEM one was the way to go.

I can’t remember if it was an OEM or not.

 

[AM500]

Ok. I’m getting 11.9v with the engine off.

When I start it up it’s actually dropping to as low as 10.4v.

Current is showing 0.03

 

[Keebler]

Ok. I’m getting 11.9v with the engine off.

When I start it up it’s actually dropping to as low as 10.4v.

Current is showing 0.03

The engine off voltage is a little low, I would put the battery on a charger and see if it charges up to over 12.2 or above. Are you saying it drops to 10.4v while starting, or after started while running? If it is during starting then that is probably OK, if it is after starting, while running then that is a big problem and would definitely effect shifting. After starting the voltage should be about a volt over the engine off voltage. Do you have any aftermarket electrical accessories installed, and if so what are they and are they wired to power that is only available when the key is on?

 

[AM500]

Will do on the charging.
Yes it drops to 10.4 while running.
No aftermarket accessories.

 

[AM500]

I assume the voltage rectifier is fried.Lol

 

[Mudder]

View attachment 310820I assume the voltage rectifier is fried.Lol

And mounted so close to the exhaust seems like a bad location for overheating.

 

[AM500]

And mounted so close to the exhaust seems like a bad location for overheating.

Yes!
And on the back side of the battery box it’s a pain to even get to.

Where did you get your OEM regulator from?

 

[Keebler]

Will do on the charging.
Yes it drops to 10.4 while running.
No aftermarket accessories.

Others, please correct me if I am incorrect in what I am saying next! DO NOT START THE P500 again until the voltage regulator is replaced. After the battery is fully changed, check the voltage and make sure it is 12.5 volts or above and holds that voltage for an hour. If so the battery is most likely ok. After the regulator is replaced then start and check the voltage again, it it is still at about 10.4 (anything below the engine off voltage) then turn the P500 off and additional troubleshooting will be required, maybe a bad wire to the regulator or something else, that is beyond my shade tree mechanic certification.

 

[AM500]

Ok.
I’ll restart the process when I get the new rectifier.Lol
Anyone know where I can get an OEM from?
Searched the web but all I found was aftermarket.

 

[Keebler]

After looking on the internet it appears that a poor ground can cause a regulator to burn out. Check the battery ground to frame before installing and using the new regulator. The wire to frame connection should be taken apart then cleaned. Use a dielectric grease on all wire connectors and the frame connection point, then tighten. I have seen previous posts that this ground connection is a point of concern for corrosion. The only other thing I would suggest is to call Honda and find out what the resistance between the stator wires should be and check them before installing the new regulator (the three yellow wires going into the regulator).

 

[AM500]

After looking on the internet it appears that a poor ground can cause a regulator to burn out. Check the battery ground to frame before installing and using the new regulator. The wire to frame connection should be taken apart then cleaned. Use a dielectric grease on all wire connectors and the frame connection point, then tighten. I have seen previous posts that this ground connection is a point of concern for corrosion. The only other thing I would suggest is to call Honda and find out what the resistance between the stator wires should be and check them before installing the new regulator (the three yellow wires going into the regulator).

I’ll check and clean the battery ground also.
Thanks for all the help Keebler!

 

[Montecresto]

I’ll check and clean the battery ground also.
Thanks for all the help Keebler!

Also FYI a 12 volt battery is fully (100%) charged at 12.6V……👍

 

[HondaTech]

After looking on the internet it appears that a poor ground can cause a regulator to burn out. Check the battery ground to frame before installing and using the new regulator. The wire to frame connection should be taken apart then cleaned. Use a dielectric grease on all wire connectors and the frame connection point, then tighten. I have seen previous posts that this ground connection is a point of concern for corrosion. The only other thing I would suggest is to call Honda and find out what the resistance between the stator wires should be and check them before installing the new regulator (the three yellow wires going into the regulator).

There isnt a stator leg to leg resistance spec, as long as they all have continuity to each other and arent shorted to ground the stator should be fine.

You can check it for output as well, though there isnt a spec for this either. As long as the output voltage is close between pairs the stator is fine.

 

[Mudder]

Yes!
And on the back side of the battery box it’s a pain to even get to.

Where did you get your OEM regulator from?

Ordered from dealer in 2019, its listed in the Wiring Harness category (have to hit show more). Just saw a huge price difference now on my local Southern Honda Powersports website.

current $169 vs $100 in 2019.

 

[HiFive]

I tried to trace where p5 is grounded from regulator/ battery ground cable, do you know where it grounds to frame? If so would you have a picture. I just replaced battery and want to make sure is not corroded or loose. 👍