2004 dodge 1500 ram hemi 5.7 quad cab with faulty cruise control. turning on cruise control and off functions normally. selecting "set" on the left hand side of the steering wheel fails to engage cruise control desired speed with cruise control on. this happens 10-15 times out of 75-90 times selected during a period of a month. also, periodically during the 10-15 times a month, cruise control will be engaged with a current speed "set," and while driving the truck slows down and prevents re-engagement of "set" on the left hand controller of the steering wheel while cruise control is still on. changed battery with no effect. throttle body is functioning normally. no blown fuses. seems that temperature extremes of 45 degrees or below and 90 degrees and higher heightens the effects of this deficiency. when turning ignition from off through intermediate to on position (not start) with trip button held in greater than 15 secs, c-code displays 67 15 then displays 00 00. truck has 66945 miles currently. *tr