Thread: Ryobi RMT1801 multi tool dead after minimal use, then resurrected

I'm not a big user of multi tools. I have had a corded one for many years which sees very seldom use but a few years ago I had to do some repairs at the side of the house atop a ladder. A cordless multi tool saw was exactly what I needed.
I have a few of the Ryobi 1+ tools, an impact driver and drill are frequent users. Since I have the batteries I bought a Ryobi RMT1801 multi tool.

It was used for one job, a few cuts up at the house bargeboards, and then put away.
Recently I had another job outside and put a battery into it. I squeezed the trigger to check everything was working - the motor went whrr for 1/2 a second and then died.


I checked online and found the Amazon reviews of this tool full of stories about units stopping dead after minimal use. Of course mine is now out of warranty.


I decided to have a look before I binned it in case it was something simple like corrosion on the battery terminals. No such luck. The switch was clearly faulty. The switch mechanism is complex, it's a variable speed trigger and the switch unit has a number of electronic bits and a small heatsink.

1_opened unit.jpg


However there are large red and black cables coming from the battery to the switch and another heavy red and black from the switch to the motor. There are smaller wires going to the LED worklight and to the side of the motor. Since this side component had heat sink paste on it I assume it's a thermal cut-out switch sensing if the motor is over heating. For the main cables I connected red to red and black to black and the motor whizzed round. The no-load current was less than an amp and the motor didn't seem to be heating up.


For my very occasional use it wouldn't be worth it to source a replacement variable speed Ryobi switch so I stuck in a simple on off switch.
I have a soldering iron and a few components from pre-retirement days so I was able to solder in a simple toggle switch. Any handyman could probably do something similar with car crimp connectors and a switch from any auto accessory store.

2_replacementswitch.jpg 2a_replacementswitch.jpg 3_junkedswitch.jpg



Result, the tool is now single speed operation without the worklight or thermal protection. It works ok and I completed my cuts outside without having to run a long extension cable.


4_newswitch.jpg
Clearly not something a professional user would want to do but for my very infrequent diy use this was adequate.

Regards

Jim