no heat

Ok, SIL has a 2013 JKU Sahara. She tells me “heat has not worked in 2 years”…???um ok. So, i started looking at it yesterday. From drivers side to passenger side its cold, not as cold, not as normal hot, and what i would consider normal hot. I understand, heater core, thermostat, blend door...

Okay I so purchased the 13 JK in summer. Heater seemed fine but that was dead summer as well fast forward to this week Colorado was dumped on with snow and I needed to use the heater boom issue number 1: heater will only blow kinda warmout of passenger side vents and cold out of driver side...