Weird Blower-Motor day!

[zerowkul98]

My wife's 4Runner's heater blower motor didnt work this morning, even after the car was all warmed up, drove around town, she could feel heat coming through the vent, but the blower was NOT working.

It's 10 degrees today, so i was not about to have my wife running around in a car with no heat, so i called my local dealership (theyve been really good to me) after i checked all the fuses (which were fine).

On route to the dealership, the blower motor started working again, and worked great the rest of the day.

Has this happened to anyone with their 4Runner before? Anyone even HEARD of this before and know possible causes?

We still brought it to the dealership, and the head tech came and said he couldnt tell what might have caused it cuz it was working now.

 

[12guns]

I had the same thing happen to my old 96' Tacoma. Not sure how similar the motors are, but mine was a simple dirty contact on the blower motor under the glove box. It would cut off at seemingly random times. I quickly learned I could jiggle the wires under the dash and it would start working again. May not be your problem, but worth checking. See if you can locate the motor under the passenger side dash. There should be one or two wires going into it, maybe you can clean the contact, bend them tighter, or something of the sort. I know it's a long shot, but worth looking into. Good luck

 

[4RBob]

yes, this is fairly common. I just recently posted in another similar thread. moisture gets into the blower moter fan (behind glove box) and freezes up. it will work again when it warms up or you free the fan by hand. there is also a TSB out for this, which is what i did myself. it includes installing a foam wedge and some silicone to keep out the moisture. surprised the dealership didn't find the TSB.

 

[PJS]

I've had a similar problem except that the fan may start off blowing as if it is on low speed (manually set on high) and then may (or may not) switch to a faster speed on its own. This occurs when I am calling for heat (ie - 80 deg inside when it's 20 deg outside) and the HVAC system is in manual mode.

It seems that the fan speed control is linked to the temperature of the coolant in the heater core and the temperature setpoint of the HVAC system. Once the vehicle has warmed up a little - I've found that I can get the fan speed to increase by lowering the setpoint for the cabin (ie- drop the setpoint from 80 to 74 and voila - the fan speed automatically increases). I've also noticed that the fan speed will increase by itself if I increase my rpms by getting on the interstate, for instance.

This is probably very similar to the way the fan operates in the Auto mode. I can't say for sure because after the first 10 minutes being frustrated trying to get the HVAC system to do what I wanted it to do in Auto - I went to Manual mode and never looked back. I love my T4R but I hate the HVAC system and controls.

 

[Bossman]

My wife's 4Runner's heater blower motor didnt work this morning, even after the car was all warmed up, drove around town, she could feel heat coming through the vent, but the blower was NOT working.

It's 10 degrees today, so i was not about to have my wife running around in a car with no heat, so i called my local dealership (theyve been really good to me) after i checked all the fuses (which were fine).

On route to the dealership, the blower motor started working again, and worked great the rest of the day.

Has this happened to anyone with their 4Runner before? Anyone even HEARD of this before and know possible causes?

We still brought it to the dealership, and the head tech came and said he couldnt tell what might have caused it cuz it was working now.

It definitely could be a problem with ice build-up on the HVAC blower motor.

The blower will start once warmed up and the ice that was causing it to not operate properly melts away.

There is a Technical Service Bulletin (AC002-07) for HVAC Blower Motor Ice Build-Up issued May 18, 2007 by Toyota.

This covers T4R model years 2003-2007.

This TSB supersedes AC003-03 which is now obsolete.

 

[Bossman]

Here is a link to the Toyota TSB AC002-07 for HVAC Blower Motor Ice Build-Up affecting 03-07 T4Rs ...

http://www.toyotapart.com/HVAC_BLOWER_MOTOR_ICE_BUILD-UP_T-AC07-002.pdf

 

[rj998]

THanks, very helpful thread

I am seeing the same issue in my '05 4runner SR5 v6. after about 30minutes with the heat on the fan starts to run. i've been keepign the A/C on after this in the hopes of drying things out.

After looking at the TSB, it looks like my 4runner is late enough in production that it already has the changes to the blower motor housing that the foam block and sealant would accomplish.

But as the TSB says, all 4runners would need the new cowl.

Question is - what changed in the new updated cowl? i'm trying to figure out if I need to bite the bullet and order the cowl, or if i can modify the existing one to come close to the update..


Appreciate any info folks mught have.

 

[Bossman]

I am seeing the same issue in my '05 4runner SR5 v6. after about 30minutes with the heat on the fan starts to run. i've been keepign the A/C on after this in the hopes of drying things out.

After looking at the TSB, it looks like my 4runner is late enough in production that it already has the changes to the blower motor housing that the foam block and sealant would accomplish.

But as the TSB says, all 4runners would need the new cowl.

Question is - what changed in the new updated cowl? i'm trying to figure out if I need to bite the bullet and order the cowl, or if i can modify the existing one to come close to the update..


Appreciate any info folks mught have.

My understanding of the issue with the original cowl was that somehow it allows outside water/snow/ice access to the blower motor. How this got past the Toyota engineers baffles me. I was advised to keep the area just below the windshield wipers on the passenger side clear of any snow or ice. So being vigilant in clearing that snow/ice (and not letting it build up or accumulate in that area) every single time you get a snowfall is important.

 

[rj998]

Sounds right bossman.

Thought I'd post an update. I took it apart today. after working late in the day yesterday, when it was 30+ degrees outside, it was frozen again this morning. Once it was 30 or so again outside it worked fine. I put it in the garage, and when I got around to working on it, it was maybe 37 in there. you'd expect to see obvious water in the fan housing right? very dry. the only moisture i found was on the brushes/contacts for the motor itself. there's a small access door in the motor housing. i was suprised to see barely a noticable amount of moisture. i'd hesitate to even call it more than a few drops worth. but it makes sense, that freezes and expands and the motor won't start up. once it's warm enough to melt, off she goes.

so i thought i'd pass on the observation that it takes very little moisture to have the fan freeze up. i was expecting and ice cube's worth of ice, more like a bit of frost. running it with the AC on for a day didnt' dry it out very much (maybe it did and i'm seeing that last bastion of moisture).

i'm thinking of putting WD40 or something similar to keep the motor contacts dry. and of course keeping any ice/ snow away from the opening at the base of the windshield.

 

[ToyotaRKEEngineer]

Intermittent Heater Fan - Mouse Nesting

Hi,

I read through all the posts, printed the latest TSB and my problem appears to have more than one issue. I have a 2003 Limited with 163K miles, still runs like a top. (have rear tail gate latch broken issue, not fixed yet)

However the heater blower suddenly stopped, assumed it was the water/ice issue but found a large nest made above the in cabin filter, I have been keeping the car outside lately, used to be in the garage - I had an issue then with cat food being stored in the same location above the filter.

Took the motor out verified it was getting power, banged it around a little, all this time it was well above freezing in the 40's after being below freezing. The motor was dead, so I drove to work today and ended up with no heat where I had had some heat before.

Put a dryer sheet above the filter the night before, had read this can keep out animals without the bad smell of moth balls, anyway I could not stand the dyer sheet smell pulled over and took it off the filter, only to discover the mouse - my assumption had been in the car over night the sheet was shreaded and a nest re-started, so much for them not liking the smell.

Got to work cold 50 minute drive, re-plugged in the heater blower on a whim and it now works.

Question is: Do I now trust the motor or replace it, implement the TSB for the ice issue not knowing if this was one of the problems?

Biggest question: how is the mouse getting in, and how do I keep it out?

Anyone else have having a mouse getting into their cabin filter area in the IP?

 

[scottm]

Stop feeding the cat? Amazing that the mouse actually used the dryer sheet for nesting, so much for not liking the smell!

 

[Bossman]

Hi,


Biggest question: how is the mouse getting in, and how do I keep it out?

Anyone else have having a mouse getting into their cabin filter area in the IP?

I had a similar issue with some sort of creature making their home in this area. Went to change the cabin air filter and there was all sorts of nesting material in there.

The advice that I got from my Toyota mechanic to help prevent this is when you are parked and about to turn off the engine, be sure to have your "recirculate air" button engaged (instead of "fresh air" coming in from the outside). This will close off an entry point for your mouse or other critters from climbing in.

 

[Glock_19]

I had a similar HVAC problem except that my truck was blowing heat full blast no matter what I set the temp on. Turns out there is a temp sensor behind the grill that was disconnected and it was screwing up the whole HVAC system.

 

[TechWrench]

This is a common problem, with many vehicles. Long story short, the critters are gaining entry to the cabin through the fresh air intake vent, under the wiper cowel on the passenger side. The only sure fix is to block their access to this vent. I used steel mesh screening (1/4") to fashion a screen cover for the intake vent, and haven't had a problem since. I call it the Anti-Chipmunk mod. :biggrin2:

 

[Bossman]

This is a common problem, with many vehicles. Long story short, the critters are gaining entry to the cabin through the fresh air intake vent, under the wiper cowel on the passenger side. The only sure fix is to block their access to this vent. I used steel mesh screening (1/4") to fashion a screen cover for the intake vent, and haven't had a problem since. I call it the Anti-Chipmunk mod. :biggrin2:

Anti-Chipmunk mod! Love it!

And to think of all those guys doing lifts, adding LEDs, bigger rims ... this is THE mod to do

 

[mrt6644]

I've had a similar problem except that the fan may start off blowing as if it is on low speed (manually set on high) and then may (or may not) switch to a faster speed on its own. This occurs when I am calling for heat (ie - 80 deg inside when it's 20 deg outside) and the HVAC system is in manual mode.

It seems that the fan speed control is linked to the temperature of the coolant in the heater core and the temperature setpoint of the HVAC system. Once the vehicle has warmed up a little - I've found that I can get the fan speed to increase by lowering the setpoint for the cabin (ie- drop the setpoint from 80 to 74 and voila - the fan speed automatically increases). I've also noticed that the fan speed will increase by itself if I increase my rpms by getting on the interstate, for instance.

This is probably very similar to the way the fan operates in the Auto mode. I can't say for sure because after the first 10 minutes being frustrated trying to get the HVAC system to do what I wanted it to do in Auto - I went to Manual mode and never looked back. I love my T4R but I hate the HVAC system and controls.

I wonder if this is related to my issue. When using the AC, the fan will slow down or speed up on its own. I do. not have the fancy automatic climate control system, but the basic manual one with a temp control and a fan speed control.