Brand new DRR electric adventure ATV not charging, DRR is clueless up to now

[kensiko]

Hello, I'm new here, I'm trying to gather knowledge to be able to solve the charging issue on my brand new DRR electric adventure ATV that has a 72V 7kWh LFP battery. The company, DRR, are clueless on the specific issue, they are not really electric engineer like me.

So here is the story:

I got the ATV fully charged, it was charged before shipment. I played around my yard for 22 km and wanted to charge it with 3 bars left out of 5. The charger does not accept to charge with error code Temperature out of range, it can be either the temperature inside the battery or the ambiant temperature measured by the thermistor attached to the charger.

So far, with DRR permission, I've opened the charger to check if the thermistor attached to it seemed to work properly, it does seem to work properly, I get 8.5 kOhms at 30 Celcius and about 9.5 at 25 Celcius.

On the battery, I've got 2 plugs, one big with 2 big pins and 1 smaller round plug with 2 small pins. They both connect directly to the charger through a rectangle plug with 2 big pins and 4 small pins.

On the 2 small pins on the battery, I get unstable measured resistance between 130 ohms and 170 ohms. If that is really the thermistor inside the battery, it's clearly not functioning properly. I have been trying to connect different resistors in place of the thermistor inside the battery to fake the temperature measurement for the charger without any luck (20 ohms up to 100 kOhms).

I was wondering if anybody in this group can confirm that in a battery pack, the temperature is measured by a simple thermistor or it's more complicated than that. I was also looking to find another charger to charge my ATV without the thermal protection. I assume that any eBike 72V charger will work, but I could be wrong.

Please enlighten me.

[james_s]

Don't waste your time messing with it, it's brand new, just insist they replace anything that is not working, you paid for a new working item, not a broken one that you have to screw with.

[kensiko]

I'm waiting for them but they don't have any other battery so it could take months before getting a new one.

They shipped me another charger, it's doing the same thing. They are working on their side to troubleshoot the issue but my guess is that they don't know exactly how it works.

They have sold 15 ATV up to now, and 3 of them have this charging issue.

[james_s]

Can you open up the battery non-destructively? Maybe you can just try connecting a pot to the charger terminals that you suspect go to a thermistor and see if it changes the behavior? It very well could be as simple as a thermistor.

[kensiko]

I exactly did that (putting a thermistor instead of connecting to the battery), I still get the same symptom.

I can open the battery, it's just nuts and bolts. But I won't do it unless DRR gives me permission as this is still under warranty.

[voltsandjolts]

Those electric ATVs look cool.

Is this the battery pack?

Code: [Select]

https://www.youtube.com/watch?v=zxGPQU22x5A
A few pictures of what you have would help the context.

Since you have two chargers, I would play with one of those first, to see if I could fool it into charging just to understand the requirements. Then your not risking the expensive pack/ATV, and it might still be the charger at fault, maybe you have two bad ones

[kensiko]

The battery pack was replaced by a different one due to supply issue and to improve protection against water.

Here are pictures

[kensiko]

Then your not risking the expensive pack/ATV, and it might still be the charger at fault, maybe you have two bad ones

I received the information this week that the charger didn't work for the 2 other persons too, so it's more likely to be a battery sensor issue, unfortunately.

[Outdoorman]

Glad I found this forum. I had the same issue but DRR resolved it it was a BMS issue. They sent a video and I repaired it myself took about 20 minutes to be careful not to ruin any wires. They told me there were a few of these that had problems took about a week to get the parts. The guy told me they changed battery companies. They also sent me in a new procedure for charging charger into battery than into wall. They asked a lot of questions about charging too. we used an extension cord and they told no extension cords they do not carry enough power to the charger. If you want I can post their video on the repair Mine is fixed and working fine I talked to Rosalina and they extended the warranty on the battery for me 

[Outdoorman]

DRR not charging solved I am on my second DRR EV ATV I was a little concerned because the first one they had an issue with like all new tech. They have really upped their game and the battery issues were software related. They have a handle on it now it was only a few out of a lot according to their website.
2x DRR Ev Adventure owner

[james_s]

Did they compensate you for repairing it yourself? IMHO this is totally unacceptable for a brand new product to require repair by the purchaser. They need to iron out the kinks before they sell them to paying customers.

[Outdoorman]

If I took it to a dealer they would have covered it like any manufacturer however calling in and plugging a lap top to the atv so they can remotely log in was like 30 seconds of work I guess I did not think that was a big a deal to whine about the immediatley said how can we help without having to take it to the dealer deal and they are so friendly every company even small ones have issues with their e products that never existed in the world till they made it may have some slight issues. If we want to encourage innovation we need to support companies like them who are innovating and not afraid to take a chance Microsoft never has a perfect product yet you allow them access to your pc to fix it almost daily! sound like your just looking for issues to whine about keener