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Electrical problem with blower switch

Howdy everyone. I’ve got a 1994 Nissan Sentra XE whose blower motor switch won’t operate the blower most of the time. I’d say somewhere close to 90% of the time, I flick it from off to either 1, 2, 3, or 4, and nothing happens.

I’ve taken apart the central console and removed the switch, but everything about it looks fine. A few years ago, something in the old blower switch shorted out and melted part of the casing, but that doesn’t appear to be the culprit this time. Even more insidious, the damn thing will power on in rare moments – usually only after it’s been left off for days and days, it seems to be. If I leave it on, it will then conk out again sometime after turning the car off, if I leave the car off for too long.

As the Starks say, winter is coming and I don’t want to be without a decent heater, and this is my only vehicle. In a pinch, I’ll do what my dad did with his old 1982 Toyota Celica and get a 9-volt ceramic space heater just to clear the windows, but holy hell that little thing was slow and weak.

Anyone have any thoughts where I should look next? There’s no obvious problems with the wires. Fuse looks fine. I haven’t removed the blower motor yet, but I’m not anticipating seeing anything obvious there, either, especially since it does start when it wants to.

Turn the ignition on, set the blower speed to high, then rap on the blower motor with the handle of a screwdriver.

If the blower starts working, replace the blower motor.

Tester

Blower motor resistor toasted. https://www.youtube.com/watch?v=YGBV0kIB7Kg

Most likely it’s either the circuit’s fuse, the blower switch, the blower motor resistor, the blower motor itself, or the blower cage is partially stuck with debris. There’s no way to tell except by testing each one. My guess, the folks above are correct, the blower motor is the one at fault. If you remove it you can hook it up by jumper wires to a 12 volt source and see if it spins ok. Carefully, as the motor is quite powerful. Check for any debris like leaves and small sticks in the blower fan area too while the motor is removed.

I own a Corolla of similar vintage and similar blower switch configuration. It won’t spin in switch position 1, but works ok in 2-4. The problem is the blower resistor. My solution is just use positions 2-4 … lol …

Thanks, everyone. I gave it (the blower moter) a good whack with a hammer and it spun up. I don’t quite have $75 just yet to replace it, and no handy junkyard nearby to source a cheap one – am I at any risk for some sort of electrical problem if I keep using this bum one for awhile?

You can get by rapping the blower motor for now.

But eventually, that won’t get the blower motor to run.

Tester

It might be possible for an electrical shop to repair it for you. That’s something a diy’er can even do, if they have more time than money at their disposal. Since it would likely take 3-4 hours to get geared up for the job, it wouldn’t pay to do it yourself if you had the $$ already to go for a replacement unit. Likely the armature needs cleaning with some emery cloth or the brushes are too short & need replacing.

Blower motors aren’t serviceable George.

They’re replaced.

Tester