Is a Bad Reg-Rectifier Killing My Honda ATV Battery?
If the voltage output from your Honda ATV’s regulator rectifier is way over normal and the machine's batteries keep getting fried, it’s time to change both the regulator and the battery.
Partzilla’s Honda ATV expert John Talley hosts live Q&A sessions on our YouTube channel every Friday at 3pm Eastern. In this session, John was asked if a bad voltage regulator could be killing the batteries of a 1999 Honda TRX300 ATV.
Honda ATV Regulator Rectifier Output Q&A
What is a good output voltage of a rectifier on a 1999 Honda TRX300? I have one that when you rev it up, it’s putting out around 18-19 volts on the battery. I’ve been having batteries not last more than 6 months. The battery gets killed in only a few days if the ATV isn’t ridden. Do you think the problem is a bad regulator rectifier?
John Talley: I would say definitely! Well, 99 percent of the time it’s going to be the regulator rectifier, because your charging voltage shouldn’t be more than 14 ½ max on an older model like the TRX300. I would imagine she should be charging it at 13 ½, somewhere in that neighborhood. But yeah, it’s definitely overcharging and cooking those batteries, and that can be pretty dangerous. I mean, if you overcharge a battery to that extent, it can actually catch on fire and/or explode. So you need to get that regulator rectifier swapped out. And you should probably go ahead and change the battery again, because chances are it’s damaged. I wouldn’t trust it.
Watch the video below to see how to test powersports vehicle regulator rectifiers.
Watch the video below to see how to test the charging system of a Honda TRX ATV.
Watch the video below to learn about the differences between battery testers and multimeters.
Want to see more live repair questions answered? See more motorcycle and ATV repair questions answered here.
