Heater only works on high...

[aman74]

01 Nissan Sentra SE

Heater only blows on the highest setting.

One mechanic said it should be a simple resistor. Another said the resistor is probably not easy to diagnose as it would be on an electronic heater control panel. He said probably to replace the blower motor first as it is cheaper than the panel.

Anyone know if there's a simple resistor to check and replace?

Thanks,

Anthony

 

[-Clayton-]

No need to replace the blower motor if it works on high. Rock auto has a blower resistor for 15 bucks and is more than likely your problem.

 

[MoparDak05]

I would definitely check the resistor first. I had this problem in my accord. It would not blow on 1-2 settings, only 3-4. I'm not sure where it is on your vehicle, but on my accord it was on the passenger side under the dash, toward the firewall.

 

[exranger06]

There's a 99% chance it's the blower motor resistor. I don't know where that one mechanic is getting his prices from. It's definitely NOT cheaper to replace the motor. The resistor is only about $22. The blower motor is about $71. I'm assuming this is the electronic panel he's talking about? Yea, that's the $22 resistor.

 

[XS650]

+3 on the resistor being the culprit.

Resistors are frequently mounted on or near the blower motor where they will have air blowing over them. Looks like yours is too.

http://autorepair.about.com/library/illustrations/bl314a-lib.htm

 

[Falcon_LS]

+4 on the resistor. Also check the resistor connector, it may be burnt and you may need a new pigtail assembly.

 

[JTK]

Yep. No doubt on the resistor block. I remember having to change one out on our 1993 Nissan Sentra years ago. The blower will default to high speed only when the paths burn up on that little printed circuit board resistor. The part still looks the same from the early 1990's. It was real easy to remove and replace. The board part of it protrudes up into the blower housing so air blows over it in an attempt to keep it cool. I got mine at a Nissan parts counter for around $20 back then.

Joel

 

[aman74]

Thanks to all!