40 Heater Only Electrical System How It Works . . . When the ignition swnch is In FlUN or ACCY positions . I blower motor circulates air from the heater I the blower motor is controlled by a 4-position swrtch - the switch sends lull voltage to the motor for high speed operation and lower voltage for the two lower speeds I power is through lusea Trouble-Shooting lt blower motor (tan) fails to operate in any switch position I make sure ign on swnchisin RUN or ACCY positions I check luse 3 check lor power at the blower switch connector If there is no power . . t I repair feed to connector It there is power t . . I turn blower swnch to HIGH I check for power at terminal 4 ol the blower motor resistor pack It there is power . . . I disconnect wire attached to terminal 4 If there is no power at terminal 4 . .. I check for power at terminal 3 ol the blower motor resistor pack ll there is no power at terminal 3 . . . check wire back to blower motor swrtch repair it needed replace blower motor switch it teed wire is OK if there is power at terminal 3 . . V I check resrstor pack it blower motor operates in only one or two switch positions t r . I position blower sWItch at LOW 0 check for power at terminal t at blower motor resrstor pack position blower swnah at MEDIUM I test lor power at terminal 2 ol blower motor reSIslor pack I posrtion blower motor swrtc'n at HIGH I test for power at terminal 3 ol blower motor resistor pack Component Blower Motor Blower Molor nesrsrur Connector (3505 Ground G60t I replace the resistor pack I disconnect connector from blower smtch I check for continuity at each of the three operating positions I replace switch Component Location Engine Companmerri at RH (lash panel RH blower housing Connector Cars On engine cenle' inward Connector care On enqrne center rorwarct Spiice 5603 Near AC Mp thermostat Splice 570 Near blower 'rclov resistor Aiiacneu ro Heater case in engine companmerri cenrerni vehicle nea'dash panel Hot when ignition Swilch D in Run or Accy lSea Page 9i FUSE 3 :53 HEA a BLOWER SWngN r) or gr Low Jr Med 4r a, BLOWER moron Connector Description anurru black Single terminal Hound black Single terminal Round crack Erngleieirnmal