sounds like heater blower running when vehicle is parked no key in ignition fan switch off position

1999 JEEP GRAND CHEROKEE

97,000 MILES • 4.0L • 4 CYL • 4WD • AUTOMATIC

DENNIS OSBORNE

MEMBER
1 POST

i think the circuit for the heater is normally open with loss of power or ground intermittently making contacts close causing heater fan to operate . It also is not constant more like switching of and on. i have been searching internet to see what relays are under dash above left foot drivers side to see if i could replace a heater blower motor relay.So far i dont see a diagram that shows one. Do think you could help?

Dec 20, 2019 at 6:31 PM

CARADIODOC

✓ASE Certified Mechanic
34,321 POSTS

There's two versions of heater systems for your model. I picked the one with automatic temperature control to start with because anything with the word "automatic" is going to have more problems. Rather than trying to figure out which parts you need, I just posted all six diagrams. See how far this gets you, then let me know where you need help.

Images (Click to enlarge)

Professional Diagram for 2CarPros Members
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Dec 20, 2019 at 6:54 PM