Heater/AC blower motor, problem solving tips! (For motor with auto climate control)

[Jayd-S]

Quite suddenly, my blower motor stopped working. I checked the fuse and it had blown. I replaced the fuse and it blew again. The blower motor was working at all speeds but it had always bothered me that even at full speed, it never really pumped out much air. I thought it must have been in the design.

I checked all threads on the forum and found that others had experienced similar problems, including reference to the blower resistor and even someone looking for a more powerful blower motor.

I pulled the blower motor and like others on the forum, found that it was really hard to rotate it by hand. Made sense to me that the extra power needed to rotate the motor meant a higher load or amperage, hence blown fuse.

Bottom line, apparently over a prolonged period of time, grease in the bottom bearing mixes with water following use of the A/C unit. The grease hardens and dries out. As a result, the bearing progressively binds until eventually it seizes. Normally, rotation of the motor actively ventilates the bottom bearing but the moment the motor stops turning, ventilation ceases. The problem arises when the blower is switched off while the A/C compressor was still operating. Condensation forms in the motor housing, collects and then drains down into the bottom bearing housing. Tip: Turn off your A/C and leave the blower on full for a minute to normalize temperature and dry out the motor housing.

A second cause of water in the bottom bearing may be from a leaky windshield or perhaps from a water leak associated with the dreaded wet carpet syndrome! I shall report on this later and document fixes for both of these as yet unsolved mysteries, even if I have to take out the whole dashboard!

If you are lucky, as I was, the first time you notice anything wrong is a blown blower fuse under the hood. If you are not so lucky, the increased amperage required to turn the motor may burn out one, any or all of the three blower resistors. This is easy to diagnose as the blower will not run on one, any or all of the lower three speed settings but will continue to operate at full speed. There is a solder type sprung resistor fuse which is part of the six sided blower resistor housing and which is designed to protect the three resistors. I have included two wiring diagrams with helpful pointers that should make it easier to diagnose any problems that you may be having. I understand that it can happen but is rare that the heater control switch also fails due to prolonged high temperatures at the contacts.

I went to Canadian Tire and with can of spray grease in hand in their parking lot was about to disassemble and lube the motor. Just then a guy parked beside me, took one look at the VX, got really excited and asked a bunch of questions. Turned out he is a mechanic who had done a lot of work on Isuzu Troopers. He recognized the blower motor immediately and said it was a common problem with the bottom bearing binding and even seizing. He recommended not disassembling it, as re-assembling without the special tools would likely affect alignment, resulting in vibration and noise. He said that a GM truck vented blower motor should fit. I did a quick internet search for GM blower motors but could not find one that would fit.

The solution therefore is to replace the blower motor with a new one or professionally rebuilt one. If you have been experiencing low air volume at the highest speed setting, you might wish to pull the blower motor and check to see if it is binding.

Now for the good news! I have located 20 new Isuzu NPR blower motors sealed in the manufacturer’s original packaging for a whopping price of USD $59.98! Originally, these motors cost around $200 to replace! Shipping is extra.

Available on eBay Canada at: http://www.ebay.ca/itm/Genuine-Isuzu-NPR-Blower-Motor-Brand-New-/160720180568

And on eBay USA at: http://www.ebay.com/itm/Genuine-Isuzu-NPR-Blower-Motor-Brand-New-/160720180568

This guy is amazing! I live in Vancouver Canada and I made two separate orders for two of these blower motors on Friday May 22. I received both, on Tuesday May 26!

I can confirm that they are brand new and packaged in the original manufacturers packaging. They are a direct replacement for the original VX blower motor with the same harness connector type and position. The motor does spin in the opposite direction but so too do the fan blades so that air flow is in the correct direction.

Since the bottom bearing on my original blower motor was seriously binding, it must have been running slower than normal at full speed. When I installed the new motor, the volume of air at full speed was noticeably greater but surprisingly, the motor fan was much quieter!

If you need a new blower motor, I highly recommend this guy. He has 20 left and has already sold 320!

Sure is good to have cool air again and plenty of it! With the increased resistance and power drain of the original motor, I am hoping to see some better gas mileage with the new one! I can always dream!

Hope you find this helpful! Will update you on gas consumption :laugho:

Helpful photos:

http://www.vehicross.info/gallery/data/500/thumbs/Isuzu_Vehicross_HVAC_Blower_Motor_circuit_part_A.j pg (http://www.vehicross.info/gallery/showphoto.php?photo=25659)

http://www.vehicross.info/gallery/data/500/thumbs/Isuzu_Vehicross_HVAC_Blower_Motor_circuit_part_B.j pg (http://www.vehicross.info/gallery/showphoto.php?photo=25660)

http://www.vehicross.info/gallery/data/500/thumbs/1_-_Blower_Motor_and_Resistor_Access.jpg (http://www.vehicross.info/gallery/showphoto.php?photo=25656)

http://www.vehicross.info/gallery/data/500/thumbs/2_-_Blower_Motor_and_Cage.jpg (http://www.vehicross.info/gallery/showphoto.php?photo=25657)

http://www.vehicross.info/gallery/data/500/thumbs/3_-_Blower_Motor_-_Cage_Removed.jpg (http://www.vehicross.info/gallery/showphoto.php?photo=25658)

http://www.vehicross.info/gallery/data/500/thumbs/4_-_Blower_Motor_Housing.jpg (http://www.vehicross.info/gallery/showphoto.php?photo=25661)

[ron234]

great INFO JUST IN CASE scenario

Thanks

[tysamigo]

Wow Jayd...

What an awesome write up and find on the motors...

Thaaaaank you :)

[Jayd-S]

Thanks Ron and Tysamigo,

I just discovered another problem that went away after I replaced the Heater/AC blower motor.

My Astral has Auto Climate Control. With the temperature setting on cold, whenever I turned on the blower from off, straight to full speed, the Auto light to the left would come on, the AC compressor would fire up and air flow automatically switched to interior source only. It was as if I had turned the motor speed selector switch to Auto but I hadn't. I dismissed it as being a glitch in the onboard computer, annoying but I could live with it.

Today, I realized that the glitch had gone away and all speed settings and auto control functionality was faultless!

So I am guessing this could be another symptom of a blower motor with tight bearings?

Hope this helps.

[mattferguson14]

I am running into all of these exact issues. Low air flow (or so it seems in comparison to other vehicles), the fact that it always sets itself to Auto mode, everything. I have been noticing that when i turn on the a/c there is a noticeable loss of engine performance, which is normal when the compressor comes on, but this is excessive. Are you saying that the blower motor could be the cause of all of these problems??

[tysamigo]

Where can I get a Blower Resistor?

[Jayd-S]

I am running into all of these exact issues. Low air flow (or so it seems in comparison to other vehicles), the fact that it always sets itself to Auto mode, everything. I have been noticing that when i turn on the a/c there is a noticeable loss of engine performance, which is normal when the compressor comes on, but this is excessive. Are you saying that the blower motor could be the cause of all of these problems??

Hi Matt.

It certainly sounds like the same symptoms. It will take you less than one minute to drop the blower motor out of its housing. Just four screws hold it in place. No need to remove the glove box. If you can contort yourself upside down on the passenger side, you will see the familiar shape of the blower motor close to the door pillar, behind the glove box and the four screws holding it in place. Once you have located the screws, you can uncontort yourself to remove them!

The motor has a foam gasket so you'll need to give it a nudge to ease it free. No need to disconnect the wiring. Just rotate the fan to see if it is hard to turn. The new motor has slight resistance but give it a hard spin from the outside of the cage and it will continue to turn for two seconds. If you have a bearing problem, it will be tough to turn and there's no way it will continue to spin after you let go.

As you can see in the photos in the original post, the fan cage was pretty dirty. I am sure that added to the decreased air flow and probably added to the noise factor too.

Good luck! :grino:

[Jayd-S]

Where can I get a Blower Resistor?

Hi Tysamigo,

I did not replace the blower motor resistor but I see that Parts Geek carries one and there appears to be one in stock for $59.63 at:

http://www.partsgeek.com/catalog/1999/isuzu/vehicross/climate_control/blower_motor_resistor.html

O'Reilly Auto Parts list a compatible resistor for the Isuzu Vehicross Base model for $56.99 although they don't show any in stock at the moment. It's a Murray Climate Control Resistor Block, at this link here:

http://www.oreillyauto.com/site/c/detail/MRY0/20145/02627.oap?year=1999&make=Isuzu&model=VehiCROSS&vi=1355879&ck=Search_02627_1355879_-1&pt=02627&ppt=C0328

Again, because I did not pull the resistor, I don't know exactly what it looks like. There is likely a difference between the VX base model without climate control and the VX with climate control. I saw one climate control resistor on eBay but it is very pricey at $178.13!

http://www.ebay.com/itm/HVAC-Blower-Motor-Resistor-Standard-RU-592-fits-99-01-Isuzu-VehiCROSS-3-5L-V6-/171707974458

If anyone else wants to throw in any recommendations here and perhaps photos of the two different resistors, it might be a good thread to keep all of the information together?

Good luck! :grino:

[tysamigo]

Yeah.. I have climate control (2001)...

Am I stuck with the pricey guy??

[mattferguson14]

Hi Matt.

It certainly sounds like the same symptoms. It will take you less than one minute to drop the blower motor out of its housing. Just four screws hold it in place. No need to remove the glove box. If you can contort yourself upside down on the passenger side, you will see the familiar shape of the blower motor close to the door pillar, behind the glove box and the four screws holding it in place. Once you have located the screws, you can uncontort yourself to remove them!

The motor has a foam gasket so you'll need to give it a nudge to ease it free. No need to disconnect the wiring. Just rotate the fan to see if it is hard to turn. The new motor has slight resistance but give it a hard spin from the outside of the cage and it will continue to turn for two seconds. If you have a bearing problem, it will be tough to turn and there's no way it will continue to spin after you let go.

As you can see in the photos in the original post, the fan cage was pretty dirty. I am sure that added to the decreased air flow and probably added to the noise factor too.

Good luck! :grino:


Thanks! I'll check it out!

[mattferguson14]

Yeah.. I have climate control (2001)...

Am I stuck with the pricey guy??

Found the same resistor here for $50 less.. Still searching for better deals too. Google key word "resistor RU-592"

http://www.carpartkings.com/standard-ignition-hvac-blower-motor-resistor-ru-592.html

[tysamigo]

OK, but before I grab one...

How do you test the resistor to see if it's good/bad? I have everything taken apart and there are 3 prongs in front of me... what do I do now?

[Jayd-S]

OK, but before I grab one...

How do you test the resistor to see if it's good/bad? I have everything taken apart and there are 3 prongs in front of me... what do I do now?

Hi Tysamigo,

What problem were you having with the blower before? Did the motor not work at certain speed settings, if so, which ones? Or did it not work at all. If you follow the wiring diagram in the original post, it should help you to troubleshoot.

With a test light, check for power at each point along that circuit.

As you have the blower resistor out, make sure it is disconnected from the battery, then use an ohmmeter with one lead on the terminal that had the Blue/Black wire attached, then touch the other lead to each of the other terminals. If the resistors are OK, you will have a reading at each terminal with a different resistance at each one.

Hope this helps.

[tysamigo]

My problem ended up being a LOOSE GROUND. I apparently left a loose ground by accident after doing a wiring project...