MMMv2 Problem....Or maybe not????

[jhautz]

Had a crazy little thing happen today with my V2. I ran it last week for a whole race day with no issues at all. Worked perfectly. Then today I took it out for a couple of test laps on a track we were working on rebuilding and I plugged up a pack turned on the radio and when I filpped the switch nothing. Flipped the switch a couple more times... off, on, off, on, off, on.... nothing. Now Im getting annoyed.

So I unplug the pack and plug it back in and flip the switch nothing. I start tapping on it and shaking the truck a bit to see if I can get it to fire, nothing....

Now at this point I am annoyed cuz it was the only truck I brought to test the track with. Out of frustration I start flicking the thing with my finger, then I tap on the switch housing with my finger and all of the sudden it fires right up!!!! I was like what the hell.?.?.? I turned it off and on a few times and it seems fine. I ran 2 full packs through it and its still fine so I'm not sure what to think. Was it the switch stuck inside or something? I'm not sure. I figure if I have any more trouble I will cut the switch off and hard wire it to the ON position.

Just really wierd, I was sure it had died a quiet BEC death, but its still kicking. I'm wondering if there is a possible switch problem that my look like the BEC problem?

Anyway, I just thought I would post this so CC could look into it as a possibility.

[e-mike]

dont worry its normal to have some issue ...you have a mmmv2

[bdebde]

Couldn't hurt to check the switch on the MMM before returning to castle.

I had bad switch in my mgm from day one, nice thing with the mgm; they default to on if no switch.

[jhautz]

OK so this V2 MMM gave me more problems to the point I couldn't get it to start up. I pulled it out and and I have been messing around with it cuz it will still start up occasionally and run for a bit before it stops. Very weird. Haven't heard of anyone else having this problem.

I started checking the BEC output voltage and when I flip the switch and it works it puts out around 6.2 volts from the BEC. When it doesn't boot up it only puts out between 2 and 3.2v randomly.

I am wondering if the BEC voltage was changed on the V2 back up to 6v from the 5.5v the V1 was supposed to be putting out. When I test the only functioning V1 I have it puts out 5.43v consistently, so this is in line with the original 5.5v spec that CC said.

Just wondering if anyone has a functioning V2 they could check the BEC output voltage on. I just found it a bit weird that it was putting out over the rated 5.5v. Of course its a messed up V2 so I have no idea.

I'm mostly just wondering if they changed the output voltage on the V2 to around 6v

If someone could check theirs I am very curiuos.

[jhautz]

OK I had the other V2 still sealed in the box that I want sure If I wanted to open. Well this 6v thing got me curiuos so I broke the seal and plugged the wires from the messed up V2 into it just to check the BEC output voltage. It is putting out 6v. It looks like CC bumped the BEC votage on the V2 up to 6v from the 5.5 V that the V1 was putting out.

I wounder why they did this and didnt mention it?

I'm still running V1's but one off them started to act up just like yours. I turned off the LVC and it works fine. I just have to time my runs now.

[jhautz]

Thats wierd... Wonder why the LVC would have anything to do with the BEC. I'm going to call CC tomorrow and see if anyone can shine some light on it and get the 2 dead MMMs I have here exchanged.

I guess I could put it back in and see if that works, but I dont really feel like it. They can do their own trouble shooting. I'm tired of it. I have 4 of these things in rotation now. As they die I send them in for replacement and toss in a new one. Hopefully the replacemnts are back before the next ones die. I just hope the 4 is enough to keep the truggy running for the rest of the race season. lol The V2s seem to be dieing pretty fast.

[tuclai]

Wow it seems like Im not the only one who got a spare MMM's as backups! I've been having a lot of issues with my MMM v2. Below is a post I put up somewhere else on this forum:

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I have been having a lot of problems with my MMM with NEU motors. My setup is as follows:

Losi 8ight T-
Tekno RC bruhsless kit (clutch/mechanical brake setup)
13/48 gears
Mamba Monster Max
NEU 1515 1.5d
NEU Engery 4s 5000mah 25c lipos
JR 9100t and JR9100s servos
Airtronics 2.4ghz receiver w/ M11 Transmitter
10 guage wiring througout

Losi 8ight B-
Tekno RC bruhsless kit (clutch/mechanical brake setup)
14/48 gears
Mamba Monster Max
NEU 1512 2.5d
NEU Engery 4s 5000mah 25c lipos
JR 9100t and JR9100s servos
Airtronics 2.4ghz receiver w/ M11 Transmitter
10 guage wiring througout

I got 3 MMM, two for use and one for backup. Well after only using each once! All three are back at Castle for repairs. Castle has told me they have stopped production/shipment on version2 untill further notice. They said the problems they thought they fixed apparently are not fixed.

My 8ight T on its maiden run at the tracks, lasted about 20 minutes and the lipo cut off kicked in. These were the temps:

Motor= 130's
ESC= 130's
Battery= 120

I took it out the next day to run up and down my street and it died after 5 minutes. The ESC would not light up unless I unplugged it from the receiver. I of course swapped parts around to make sure it was the ESC and it was. The only way the ESC turns on is if I disconnect it from the receiver. CC said they have seen this in about 5% of the new v2 batch so please return to them for repair.

I took the Losi 8ight B out for its maiden run at the tracks, and after about 20minutes it died. Brought it back in and temps were as follows:

Motor= 130's
ESC= 130's
Battery= 120's

I thought it died because of lipo cutoff, so after about 20 minutes of letting everything cool down I took out a fully charged lipo and as I was plugging it in the ESC went up in flames! Turns out one of the capacitors (3 total) blew up. CC said this is because the ESC was working too hard to keep up with amperage draw because the battery was not enough. I thought to myself, with a NEU 2050kv motor and a $250 NEU 4s 25c 5000mah lipo if this is too much for the ESC to handle then the ESC's got problems! But they said send it in and they will repair.

I took the Losi 8ight T out with the third ESC and after 5 minutes the car died. Brought it in and turns out the top half of the ESC fell off from the base when I was driving and it tore out the power swtich and fan connectors to the circuit board! Again, CC said this was a design flaw they are working on to fix!

So I waited like 5 months for MMM v2, just to play with all three for less than an hour and have to wait another few months!

Above is just food for thoughts for those considering MMM. I dont know, maybe Im just bad luck? If you guys look at my pictures on the link below I went out of my way to make sure all wiring and cabling is as solid and clean as possible! Heat was obvisously not an issue with these three failures.

http://good-times.webshots.com/album/562025697XGWJlX

[RBMike]

tuclai, those temps are way too high.

[tuclai]

You know what my bad! All the temps should be in the 100's! Sorry for the confusion!