Have 2 DX3-SR315 radios . In storgae for 3 years , new . Streering worked OK . Needed full brake to stop motor . Tried endpoint adjustment . Now streering goes full left or right , no center point , jitters at center point . Throttle completely dead . Factory reset , tried every combination of setting endpoints for steering and throttle . Called Horizion , sent me user manual . Watched every Youtube video I could find . No go . At a loss . DX2 works with SR315 , so receivers are ok . Using 4.8 nimh battery and 2 servos . Old dude in my late 60's . Dummy , I guess . Can anyone walk me thru ?

Tried rebinding or firmware update?

Rebind the SR315 to TX , W/O ESC and Steering servo. Then recalibrate throttle neutral, full throttle and braking. Once you connect steering servo to should go to center position. Recalibration ESC follow manufacture instruction. If you dont have manual on rebinding go to youtube for Spektrum rebinding

did you calibrate your esc?