Ryobi RM480E 38" riding mower won't move!

[MowerMike]

Just for the benefit of the trolls trying to derail this thread, the lawn mowers being discussed here use SLA batteries and NOT Li-Ion batteries. Not surprisingly, none of the problems being discussed involve fire. I personally feel sorry for the poor souls that have been the victims of the horrible Ryobi QC in these very expensive OPE.

 

[bertsmobile1]

no question modern batteries are approaching the energy density of low-grade explosives. In the industry I just retired from, they had to limit shipping of coin-cell and other batteries to non-passenger aircraft due to the danger.

and quick searching does indicate 'battery fires' are more problematic to deal with. Likely due somewhat to less experience and training by firefighting agencies.

But most of what I saw supported more fires in ice vs ev vehicles. Or one source saying there was insufficient data to support claims either way. Ice vehicles also have a battery (flooded lead cell) , I remember some Ford products recalled due to some fires that started from spontaneous shorting/overheating of something underhood part when parked.

In most fires a fuel is oxadised by oxygen from the atmosphere
With Li batteries the oxadizing agent is the negative plates so once they start "burning" then there is no way to stop them other than freezing in something at least as cold as liquid Nitrogen.
It is not a case of training or better proceedures, it is simply a chemical reaction that can not be stopped till one of the reagents has been fully consumed
Fire is a redox ( oxidation-reduction ) reaction of a fuel being oxadized and the flame we see is a byproduct of the reaction.
Physicasits have been argueing about exactly what a flame is since the first time we lit a fire
Toss a burning Li battery under water & it still burns, you just do not see any flame
the instant you lift it out then the flames reappear

 

[MowerMike]

This forum needs better moderation. There's too much trolling and hijacking going on here. It's simply rude to hijack someone's thread and change the subject completely. If y'all want to start another thread about the flammability of Li-Ion batteries, then go for it, and get the hell out of this thread.

 

[Ryobi sucks]

Unbelievable!

I thought I did so much research on the Ryobi RM300e but clearly I was way wrong. I bought it on June 4th I tried to mow for the 3rd time ever it lasted all of 5 minutes then suddenly I had the same issue so many others on here have. I could not move forward or reverse all the mower does is beep at me when I do try to move actually specificly it beeps 8 times. The blade will engage, lights work, batteries full. It just won't move. I'll call Ryobi tomorrow to see what they say but if it's not a simple I mean super simple fix (I bought this mower specifically because they advertise it as a less maintenance alternative to gas and I know absolutely nothing about engines, gas or electric) I'm taking this Lemon back to Home Depot.

 

[Mowitor]

Hi Mowitor. Thanks for the kind words - just trying to help out others anyway I can with my sagas.

Great point on the thermistor. Just went out and confirmed (cut off the coating on my failed controller), that what I thought was a thermistor is an unused connector (on the drive controller) not shown in the service manual (my bad) - I'll edit my previous post. This is a bummer, as I was hoping there was some sort of correlation of heat related shutdown - as many seem to post that the mower "resting" for some time gets it to move again (odd if not somehow heat related). I also was confused on one person saying they had an "H" on their gauge. Would like to understand that response better.

On opening the controller box, "goo" is probably not the best description. Its goo that the entire electronics board was dipped in and then the goo hardened (almost plastic like). This I believe is to conduct the heat to the casing. As a result - I don't see how you can service anything. Its completely encased in goo.

On the interlock, I tried to understand the wiring, but as you say - its confusing. It appears plugging IN the charger shorts two port pins which in turn cuts off main power availability. Its tied in with the seat switch also. If your port "short" remains, that would explain the lockout. The service manual has a connector to connector wiring diagram but not really a schematic diagram - which is what is needed. Its got to be a simple bypass somehow however. I think the port assembly is relatively cheap compared to a controller. Are you saying your mower is completely down (locked out due to your port issue)?

Maybe the coating on the board is for waterproofing it. My fish finder's board is dipped too, it's to protect the board from corrosion. That stuff more likely traps heat than conducts to the housing. Maybe a failing component heats up in there which causes a short or open. Also possible that the manufacturer put a thermistor on the controller board.

I think the "H" that you are referring to is on everyone's gauge. It's the only dot that lights up unless you do a mod. Hours.

Definitely my charge port is toast. There's a little square area at the top between the positive input and the top sensor port. I'm guessing there's some kind of circuit/relay that got damaged in there. Anyhow, since it wasn't working I couldn't measure voltage signal from the blue wire. It appears that wire should send 48v (also tested and not 12v not 24v) to the relay interlock which closes the power interrupt loop. I'm not going to install another charge port but if anyone has this symptom an easy test would be to check the voltage coming from the blue wire at the back of the charge port (not in the Ryobi troubleshoot and test document). As you mentioned, the blue wire voltage is interrupted when the charge plug is plugged in. That in turn opens the relay and disables power.

 

[Ryobi sucks]

Unbelievable!

I thought I did so much research on the Ryobi RM300e but clearly I was way wrong. I bought it on June 4th I tried to mow for the 3rd time ever it lasted all of 5 minutes then suddenly I had the same issue so many others on here have. I could not move forward or reverse all the mower does is beep at me when I do try to move actually specificly it beeps 8 times. The blade will engage, lights work, batteries full. It just won't move. I'll call Ryobi tomorrow to see what they say but if it's not a simple I mean super simple fix (I bought this mower specifically because they advertise it as a less maintenance alternative to gas and I know absolutely nothing about engines, gas or electric) I'm taking this Lemon back to Home Depot.

Called Ryobi and they said I need to push the mower around a bit to reset the Motor control sensor. I did and still nothing so they said it needs maintenance. I told them I've had this mower for 2 weeks and they said oh just take it back. Definitely will never buy a Ryobi again

 

[Slowpok22]

Have the same issue, with the Ry48111, found the test list, and went through them all, and finally got stuck on the hall sensor, had to hook up a phone charger, got the 5 volts, but when hitting the 3 wires got all sorts of different readings, but no movement when turning the wheels,
Called ryobi and chatted with them a while, he told me I could order that part and sent me the number to call, we'll you can't get that part, called ryobi back and this time he said I couldn't, can order the drive motor? Guess not gave me a part number for the whole transaxle.
Before I pull the trigger and spend $500, thought I'd get an an opinion, to see if I'm missing something.
Jeff

 

[Slowpok22]

Have the same issue, with the Ry48111, found the test list, and went through them all, and finally got stuck on the hall sensor, had to hook up a phone charger, got the 5 volts, but when hitting the 3 wires got all sorts of different readings, but no movement when turning the wheels,
Called ryobi and chatted with them a while, he told me I could order that part and sent me the number to call, we'll you can't get that part, called ryobi back and this time he said I couldn't, can order the drive motor? Guess not gave me a part number for the whole transaxle.
Before I pull the trigger and spend $500, thought I'd get an an opinion, to see if I'm missing something.
Jeff

 

[Slowpok22]

Anyone know of a way to bypass the hall sensor to test

 

[jjtokarz]

My RY48111 today stopped going in reverse only. Admittedly I was driving through some overgrown brush so I'm thinking maybe connection got broken somewhere. I will update with what I find. Going to check electrical connections first. Hoping to get a repair manual for the mower that shows how to do this but do not have one currently.