I was changing out my interior bulbs last night for led bulbs. I was changing the drivers vanity mirror light and as soon as I put the new bulb up to the contacts the lights cut out. Didn't think anything of it. Probably a fuse blown that I can fix when it's not rainy and cold out. Fast forward to after work we're going to dinner and the car is cold inside, heat to the max, car is well warmed up, but no heat. The windows got worse and worse fogged up. No heat was blowing. Everything seemed like it was working. Nav screen showed that I was changing modes. Just no blower. Is the blower tied to the interior light fuse? I've seen so many things. Bad relay. Bad BCM. Unhook the battery fixes. Is it just a fuse or something more?

 

Is the unit blowing air AT ALL? If the motor is blowing but the selector isn't switching to HOT air then you might have cooked something inside the AC control head.

Check fuse # 10 in Fuse Block - J/B behind the driver footwell access panel for the interior light fuse.

Check fuses # 3, 6, 19, in Fuse Block - J/B and fuse # 49 in the IPDM for the heat not blowing.

 

Thanks for the fuses to check. It's not blowing at all. At first I thought it was just because it wasn't warmed up so the auto function wasn't blowing yet. Once the car was well warned it still wasn't blowing and manual control did nothing either.

 

If it's not blowing at all the likely culprit is the blue relay plugged into the BACK of Fuse Block - J/B.

Disconnect the battery negative wire.

Remove the entire kick panel, not just the access cover. If you have the little foot rest dummy pedal thing you can just pull up on it to remove it before you can pull that panel all the way off.

Next remove a couple of 8 or 10mm bolts that hold down Fuse Block - J/B, pull it forward slightly and you will be able to see the BLUE colored relays on the back of the fuse block.

Autozone carries the OEM Nissan relays for whatever reason so you can save money by buying them at AZ rather than going to the dealership. Other parts houses will likely carry a generic relay which should work just fine.

If you want to test the relay for function just swap it with one of the other blue relays behind Fuse Block - J/B, they're all the same relays, pay attention to the orientation of the relays as you remove them since they're sort of a PITA to get back in because you're doing the work mostly blind in a very tight space.

This picture should match your Fuse Block - J/B for a 2007-2008 sedan.

 

I recommend writing on the relay with a sharpie so you can keep track of the first one you removed if you're going to be swapping it with other relays

 

I do believe it's the relay. In changing out the fuse for the interior lights I guess I left the car turned on but not running to long. Ended up having to jump the car. In driving it around to boost the battery back up, the heat just magically kicked on. I believe I heard the relay click right as it kicked on.

 

Definitely sounds like the relay that's EXACTLY how mine behaved when my relationship started to fail. Driving around would cause enough vibration through the chassis to cause it to unstick

 

Lol f'ing Google auto-correct!

RELAY!!!!! not "relationship". I'm just going to leave that post unedited though because it's hillarious.

 

 

Thanks all. Instructions were spot on. For reference, you don't have to remove any bolts. The fuse box can be pulled off the mounts by depressing two tabs and sliding it off.

The real test will be in the morning when it's cold. It's tended to work after the cars been running for a while.

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