error code 3 mean on a tx 5.0 sportcraft. I now how to fix it. I just did. And I didn't pay to find out from the internet. wbten70@yahoo.com. Unplug it. Take off the cover its 4 screws. 1 on each side and 2 in the front. On the right hand side there is a plastic wheel that is on the bar that rotates the belt. Its got spaces on the end of the wheel. Its passes between a mounted sensor that has a black, red, and white wire coming from it.as the spaces in the wheel flicker thru the middle of the sensor, the computer tells the speed rate. Thats how it knows how fast it goes. Mine was cracked in half and out of the sensor. The tx would fire up and shut down and blink 3 within 7 seconds of running. All I did was buy that glue that has 2 tubes on it like a syringe. Get a index card and fold it a few time to make a paper stick. Next make sure the wheel is ready as possible to be held together first. Then you bust off the cap to the glue squirt it on a piece of paper and mix the 2 glues together, stirring it. You only have a little time cuz the glue reacts to itself and starts to harden fast. Paint the glue on the bar, thick and quickly hold the plastic wheel together on it. Then just gob or let the glue drip where it is cracked in half. Key point! While you are holding the wheel together make sure its lined up with the sensor as evenly in the middle of it as possible. When the glue starts to hold, roll the bar with your hand to make sure the wheel is spinning freely thru (in between) the sensor. If it wiggles like its crooked its ok as long as it doesn't actually scrape or drag on the sensor. Put the cover back on and try not to step on the cover or on that side of the cover. The cover flexes and thats how I think mine broke. I got kids that think its a jungle gym. If the wheel is on and ok, it could also possibly be that the sensor is dirty. p.s. while you got the cover off sweep out the dust bunnies
WlidBill, October 2008