Hi I have a 2002 Jeep GC- 4.0 with manual temp control. I did have an issue in the past with the blower motor not working at all....since then I have replaced the motor and the resistor. The three lower speeds of the blower work fine, but when I position it to high it does nothing. I also slaved in a known working control panel - the result was the same - no high speed fan. Just wondering what else it could be - is there a relay somewhere in the wiring for the manual control system? Any help would be appreciated! Thanks in advance

Regards
John L.