is the battery pack in the truck plugged into the power switch and likewise the powerswitch plugged into the reciever and in the right direction? usually all the wires go in the same pin on each plug in the reciever power and servos I mean. Try turning the switch on the truck on and off a few times to see if the throttle or steering jumps a little bit, they should, then turn the transmitter on and off a few times to see if anything happens