hrm... I don't know if your problem is with the 4 in 1 or not... but the light going red on the 4 in 1 is perfectly normal.... all it means is that it is approaching full throttle.

you might want to check and see if everything is moving alright, and see if it needs any lube or if the motors are too tight against the main gears. I guess you could go ahead and replace the 4 in 1... it might solve your problem, but it also might not =(