Fan not working- motor or controller?

JimRochester · 01-15-2007, 10:13 AM

Hey guys. I have a 99 Grand Am 3.3 and the fan is not working at all. I did a search and checked a few of the past posts but they seemed to deal with heater cores and blower motors. I'm thinking it's the fan control? Don't blower motors usually start making noise before they give up? It's freezing rain outside so before I start rolling around outside I'm trying to get all my possibilities. I don't relish tearing into the dash in the middle of winter so any advice is appreciated.

xeroinfinity · 01-15-2007, 10:38 AM

Hey, btw your GA has a 3.4

So your fan as in the heater blower is not working?
Does it work on any settings?

Years ago they were under the hood where they usually got wet and when they failed they usually made all sorts of noise. But yours in on the pass.side under the dash. Which they still do get wet when your HVAC drain becomes clogged.

Check the fuses and relays first.
Drivers side IPC/HVAC Batt
Pass.side HVAC Blower motor
Under the hood fusebox, #13 mini relay Hvac blower
maybe #53 Fuse.

If those are good then pull the kick panel off on the pass.side floor. Some 5.5mm(or 7mm) screws hold it on.
Three screws hold on the blower motor.
Be sure and check all your plug connectors for corrosion.
As this can happen and make your blower not work.

If your blower works on 3-5 settings then its your resistor which is behind the blower. Same screws, 2 of them, a real pain to get to laying on your head.

If you need anything else just ask!

JimRochester · 01-15-2007, 01:05 PM

You're right, it is a 3.4. I was thinking of my van which has a 3.3.

It isn't working on any of the settings, won't blow hot or cold, so I know it is either the motor itself, the switch, or one of the wiring components connecting it all together. I'm fine at replacing things I know are wrong. I just never have the patience to troubleshoot. I'll try the your suggestions, it's much better than starting to tear things apart and hope I guess right. Thanks for the help.

xeroinfinity · 01-15-2007, 04:54 PM

I'd start with the fuses then move toward the motor or resister. Usually the resistors go out and it works on 3-5, but they can just die altogether.

With a voltmeter you can test the wire connection plug for voltage.
While selecting the blowr speeds,
you should see a variance in voltages.

If theirs voltage present then the blower is probly faulty.
To be positive its the motor you should test it from the battery with wires.

If thiers no voltage, and the motor tested OK then its likly the blower resistor.

JimRochester · 01-16-2007, 01:07 PM

Passenger side fusebox had a blown fuse. The fan has never worked on 1 or 2 but that was never a big problem. We'll check the rest of the stuff when the weather is more accomodating. Thanks for the help.

xeroinfinity · 01-16-2007, 01:57 PM

Ya, that fuse will probly keep blowing from time to time till the resistors replaced.

And you're welcome!

Bassasasin · 01-16-2007, 08:14 PM

I thought the blower motors have a history of failing..

Good Luck

xeroinfinity · 01-16-2007, 10:23 PM

Quote:

Originally Posted by Bassasasin

I thought the blower motors have a history of failing..

Good Luck

If it gets wet, yes it will fail quickly.
This usually happens when the hvac drain is pluged.

The older one's were under the hoodm and got wet regularly.

jwalker1970 · 01-18-2007, 10:29 AM

**Common problem with GM's** Causes heater fan resistors, heater fans, and heater fan fuses to fail.

I have fixed several 99 and up Grand Ams, but also 01 Intrigue, 03 Monte, and 00 Alero.

BEFORE REPLACING FAN RESISTOR..... Remove heater blower motor and look for signs of moisture coming out of the heater motor or heater case. The easiest test to know for sure is to turn on a hose and prop it under the wiper, running water upward on the passenger side windshield. With the fan motor absent from the case, you can look up inside and see water dripping or running down.

Most common cause for this is a faulty weatherstrip under the cowl vent cover. The weatherstrip gets loose or falls of entirely allowing a free flow of water of the passenger side of the windshield directly into your heater case. If you've noticed water on your passenger mat after a heavy rain, this is most likely the cause.

Generally, your fan and resistor won't fail until it freezes.... locks up the motor and fries the resistor & hi speed fan fuse.

EASY FIX: Remove wiper arms and cowl vent cover. Directly below the windshield there should be (about 24") weatherstrip on the bottom lip of the "cab" portion of the car, directly above the heater intake opening that diverts water around the air intake. I simply remove and clean the weatherstrip, and re-install using a modest amount of black RTV in the pinch groove. Make sure to tape the weather strip in place until the RTV sets up (overnight). Then I put a skim coat along the top edge of the weatherstrip so the water can easily run off either way. MAKE SURE: that the weatherstrip is sealed firmly in place before reinstalling the cowl vent, or it WILL pop off, defeating your fix. Good Luck.

xeroinfinity · 01-18-2007, 11:23 AM

Quote:

Originally Posted by jwalker1970

I have fixed several 99 and up Grand Ams, but also 01 Intrigue, 03 Monte, and 00 Alero.

BEFORE REPLACING FAN RESISTOR..... Remove heater blower motor and look for signs of moisture coming out of the heater motor or heater case. The easiest test to know for sure is to turn on a hose and prop it under the wiper, running water upward on the passenger side windshield. With the fan motor absent from the case, you can look up inside and see water dripping or running down.

This was only the 99-01 N-body's, most would comment about a mildew odor, windshield fogging, or wet carpet on the passenger side. And in ambient temperatures below 32° F, the blower may not operate due to ice.
The foam water dam under the black beauty panel may be mis-positioned, missing, or not adhered properly.
Remove and discard the original foam part. Clean the metal surface with an alcohol based cleaner. Install the new part, properly center-ing the part over the HVAC air intake opening.

- On vehicles built without a foam dam and old style beauty panel, Install 18 mm foam this fix.
- On vehicles with no foam, or with 18 mm foam and new style beauty panel, Install 25 mm foam.

Thiers actually at leaast 4 TSB's just on this case.

Quote:

Originally Posted by jwalker1970

Generally, your fan and resistor won't fail until it freezes.... locks up the motor and fries the resistor & hi speed fan fuse.

This is not realy true either.
As the "Original resistors" were defective and burnt up.
If the motor frooze then it should pop the fuse and not the resistor. But when the resistors blown the fuses can blow at any time depending on where the break is on the cicuit & th eamount of miosture in there.

The new resistors are coated with plastic(as seen in pic above) which makes them pretty much water resistant (proof).

And I wound not waste my time gluing anything under the hood with RTV, it'll just fall off.
You need the contact cement and the proper foam piece.

Call any dealer and thier shop should be able to tell you what the part # is or what type of foam to use.
As I cant seem to find it myself right now.

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