Blown MFC? Another head scratcher

[Snowman3725]

Hey guys, so I just picked up the truck puller 3 motor 7.2v and a 4:1 aux trans reducer for my king hauler. Things went very smoothly installing and what not, but some strange happen. It appears that the motor has somehow "reversed" itself. What I mean is when I stick left to enter first gear, the motor spins at its highest output, while when I Stick right to enter 3rd gear, the motor spins at its lowest rpm, which is completely opposite from what it should be. I check the motor and trans on another KH and it works as it should, left being slowest, right being fastest. What happened here? Has the MFU malfunctioned? I'm dumbfounded. I tested the stock Tamiya motor and no difference. Anyone ever had this happen before?

[heavy_duty]

Hello,
I experienced this before myself and I was stumped.After searching around and coming up empty. I called Tamiya and spoke with customer service. They told me to return the unit and they warranted it. They sent me a replacement unit. I didn't tell them how long I had the unit or anything. They had heard of this problem before. Good luck. Keep us posted.

Ed

[Snowman3725]

Thanks Ed, so I take it the MFC is no good? Did they give you and reasons as to why this happened? I'd like to know if it's just a defect or if I did something to cause it. I had a pretty good load on it, almost 50 lbs before it happened

[Stepside]

Is it an issue w the coupler switch? Have you tried it with the coupler switch engaged? In all of my rigs, I have the coupler switch elimated and the circuit wired together so the MFU thinks it's always hooked up.

[Snowman3725]

Hmmm I can certainly check it out. I can't see why it would be that, but hey you never know. If it is that you will be my best friend

[Stepside]

Any update?

[Snowman3725]

Yeah I checked the coupler switch and everything looked fine. I Swapped mfcs from another truck and it works now. Still don't know what caused it though

[dabears]

You sure you didn't reverse the channel on the transmitter? cause that would cause it too. have you tried rebinding the rx and tx, and then following the MFU set up again? try switching your steering for your shift on your receiver or even the mfu output. is it normal or reversed. Don't think you have a bad mfu think its an error somewhere else maybe?

[Snowman3725]

I checked it on a different truck with the same results. I ended up tossing it and got a new one

[mavrick0]

You do realize Tamiya would've fixed it for probably nothing. There's pretty much a lifetime warranty on them.