Scooter Service Q - UL370 "Rascal Fold & Go"

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Scooter Service Q - UL370 "Rascal Fold & Go"

Postby ex-Gooserider » 26 Aug 2017, 01:18

I just got asked to help diagnose and fix a UL370 Rascal scooter - one of these 'friend of a friend' deals... I found the typical not very informative manual online, and a lot of places listing parts, but nothing really useful...

The owner brought the scooter in earlier this evening, and I got it running, but not in a way that gave me a lot of confidence that I had solved the problem properly... (or as properly as one can get with a scooter like this...)

The scooter is a now discontinued unit, in the 'shopping center / portable' class - small, breaks down (sort of) for transport, slow, weedy....

The unit has a main frame, with a quick detachable battery box, seat, and drive train. The tiller assembly folds down to transport the frame / tiller / front end assembly....

Battery box has 2X 12V 10A (some parts sites had diff. size options) batts of the "UPS" style that connect with spade / tab terminals, and a holder w/ 2 fuses. The charger plugs into the battery box with an XLR plug. The chair side has a four position connector, only 3 positions populated, battery power and the inhibit pin from the XLR plug.

The Drive train has 4 contacts, two for the motor, two for the 24V brake. The freewheel lever works a switch that opens the brake circuit and releases the brake. The single motor runs through a differential, that is always engaged.

The controller is P&G S-Drive, D50746.03, 45A (made in China) I didn't see the 4-pin molex / ATX connector for programming, but I think that is because I didn't realize that there was a removable cover over the connection area on the controller... :oops: First time I've ever seen an S-drive in person, what can I say....

I didn't open up the tiller, but it just had a speed knob, drive paddles, a battery LED meter, horn and key switch.


Supposedly died while driving, when she got it home it would turn on, but LED would flash in a pattern that she thought was 'sleep mode' and power cycling didn't wake up....


I checked the battery - was about 25.9V on my cheap meter when I got it. The charger was a brick that looked like a laptop charger and said it was 28.8V, but when I plugged it in my meter had a little over 30V, it also read the same when I unplugged it and measured the pins in the XLR plug directly. Not real happy with the charger voltage, but seemed OK, or at least didn't match the symptoms....

I then looked at the drive train - after figuring out the contacts where it connected to the chair, I hooked up a 24V supply I had handy, and verified that the motor spun in free-wheel, and that the brake clicked on and off... Again no obvious issues...

I flipped the chassis up on end, and found the controller, but didn't do much on it because of the cover issue I mentioned earlier.

I cleaned the contacts on the drive train and battery box, and put things back together to get a better feel for what it was doing - dead, except that leaning just right on the battery box would get power up with flashing error codes on the display.... The flash code seemed to point at a controller error.

I pulled the battery box back off and opened it up... I found the wire on the negative battery terminal was disconnected, which MIGHT have happened when I pulled the cover off, or it may have been almost off, and just making intermittent contact... (If it had been totally off when the scooter came in, I wouldn't have gotten decent results like I did in the initial testing) I put it back on, and put the box back together... When I put the box back on the scooter, it powered up and seemed to be working OK.....

At this point the owner opted to say that rather than trying to tear the unit apart more looking for a definite fault, she would rather take it as now working and then bring it back if it gave another failure... I don't feel real confident in the fix, given that I didn't find an obviously identifiable problem, but she was happy...


1. I found another thread that suggested that it would be possible to program through the XLR plug, rather than trying to connect directly to the controller with the ATX plug - is this likely given that they seem to be using the inhibit wire (which I understand is also the programming wire)?

2. Am I correct in my recollection that the Pilot + software will also work on the S-Drive controller?

3. Anyone have the P&G tech manual on the S-Drive controllers? I did a lot of searching, and couldn't find one on line - lots of other P&G manuals but not the S-Drive....

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