I had this problem last year, but the front heater was working so I just dealt with it. Earlier this winter the front heater wasn't blowing hot air when idling. I found a suggestion online to raise the front of the vehicle, open the raditor reserve tank, and run the heat on full (AC off) for 15 minutes. Apparently, to get out air bubbles. This didn't work right away, but the next day the problem was solved and I now have hot air while idling. I was hoping this would solve my rear heat problem as well, but it didn't. I have tried every combination possible with the front and rear knobs, but no luck there either. Any other suggestions I could try, before taking it to the dealer (I am well past my warranty)? Thanks
Rear heater only blows cold on 2005 Nissan Pathfinder
by cc_spruce in Altoona, PA on January 30, 2009
ANSWER by patrick mannion , January 30, 2009
There are no Service Bulletins from Nissan that specifically address your problem. There are several variances in wiring diagrams relating to the heating and air conditioning system on your Pathfinder depending on whether your Pathfinder has automatic climate control or standard mechanically operated heating controls. Two things that come to mind is there is a fuse that controls the blower control switch in the rear, a separate blower motor and another fuse controls an electrical relay and powers an electrical motor that "boosts" coolant flow to the rear heater. I am afraid you will have to bring your Pathfinder to your local dealer or independent repair shop that has knowledge of Nissans or are confident in electrical diagnoses.
ANSWER by Visitor , April 07, 2010
If you have an 05 Pathfinder check the rigid pipes that run from the front of the car to the rear heater matrix. The design of these is ridiculous and they corrode through resulting in coolant dripping out over the rear of the car. The place to look is just behind the rear offside wheel (easier if you take the wheel off) I noticed this when changing rear brake pads on my low mileage 05 T-Spec. You will see where the two pipes are retained together that road salt is trapped and the thin walled aluminium tubes rot through. Mine have just failed and Nissan want over £1, 000 to replace them!!! The job requires that the body be lifted from the chassis to gain access to the pipes. What a poor design feature on a not inexpensive vehicle!! CHECK YOURS ASAP!!!!