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Ok, I'll try to keep the story part of this short. About a week or so ago I wrecked my 12L4. Tagged a post on the tennis court and spun it around. When it came to rest, no movement. When I retrieved the car, the ESC case was opened, not broke, just opened. Reciever case was poped open on one side, easy fix. The motor was beeping while the ESC (Futaba 330CR BTW) LED, still powered up, was steadily flashing. Had roughly half a charge left on the battery. I shut it down and bring it inside to cool off and snap the ESC back together (the servo tape held to the chassis just fine ). Kept doing the same thing, steady beep...steady flash...no go. No nuthin' except for the occasional twitch of the servo and rev from the motor, not by my control. Thought maybe the ESC shorted so I ordered a new one from Tower, a Futaba 401CR. Might as well upgrade, right? Got the ESC.....same problem, except now with multi colored LED....I wasn't amused. Neither speed control will let me complete the setup of neutral, full throttle, full reverse. Second Tower order, a new reciever. Thought I'd have it licked. Got it today, no dice. Battery connections are fine, motor seems in good order, servo works so please... after the better part of $100 later, someone please tell me it was/is something simple like motor capacitors or a crystal set cause I'm running out of parts to replace, out of money to replace them with and I'm well out of patience.

my guess is a bad crystal.
esc beeping with the futabas indicates no signal from the RX. (I don't recall other brands doing that)
One other possibility is a bad servo. I have had a servo with an internal short or bad motor, and it caused a high current drain on the BEC system which caused the RX to work erratically.

Try the setup with the new esc and new rx, no servo. if that doesn't work it is likely the crystal.
do you have any other radio gear from other cars to swap out?

Are the transmitter batteries fully charged? The constant beeping and LED flashes are shown byt the Futaba manuals to mean, "(Amp power left on alarm) When the transmitter power was turned off first." Which means your car isn't receiving the signals from the transmitter, because there is none. First place I'd look is the transmitter. Make sure the crystal is plugged firmly into the back of the radio, as well as the receiver, and that the antenna is securely screwed into the base of the transmitter.

Might have a cracked Rx crystal, too. Have another radio to swap the same band crystals with?





And why are you playing with a 12L4 in a tennis court? 3-4mm of ground clearance on dirty pavement is asking for big trouble and a seriously broken car. Those cars are made for ultra smooth surfaces, not bashing around on a tennis court. Get a beater buggy or stadium truck for that.

Tx batteries are good. Tried without the servo to no avail. No other gear except for a servo and that's already been ruled out. I already knew what the led + beep meant, that's what led me to replacing parts. Antenna screwed tight. Crystals snug. Guess I'll source me a new crystal set. Some how I knew it'd be something simple.

And as for the court, it's all I got. It's fairly clean. Better than the basketball court.

Have you tried using only a servo and dry battery setup (e.g no speedo or motor)?

Jay Dub wrote:Have you tried using only a servo and dry battery setup (e.g no speedo or motor)?

Yes, I have. The servo twitches once then nothing. Thanks for the help guys. The reciever was affected so little on the spin out, I didn't even think about posible damage to the crystal. Wis I would've checked that first. Anyways, I'm gonna exchange the new reciever for a crystal set and *cross my fingers* that may take care of it.

" And why are you playing with a 12L4 in a tennis court? 3-4mm of ground clearance on dirty pavement is asking for big trouble and a seriously broken car. Those cars are made for ultra smooth surfaces, not bashing around on a tennis court. Get a beater buggy or stadium truck for that. "

I am guilty of this as well, I guess the reason is ease of accessibility and the fact that well set up pan cars are agile and blindingly fast how can you not want to unleash that whenever possible. I am 1/10 scale myself but similar issues, kinda rough on the car but silky smooth on the mind, body, and soul………

Smitty hope this gets your problem solved

Kcal wrote:Smitty hope this gets your problem solved

Thanks, me too. It would be so much easier to diagnose and fix if we had a real hobby shop here in town. The closest we have is a Hobbytown USA and those fools only carry 27mhz for the RTR cars.

Got a new crystal set today from Tower (finally) and that solved the problem. My 12 is back up and running again. Thanks again for the help.

Congrats! Glad to hear you got it figured out and running again.