Heat only blows on high

[Jakw]

1-3 fan blades don't blow, but 4 blades does. I already changed the fuse in the driver's side kick panel with no change. What's next?

[GerryO]

I recall a diagnostic display mode that you can put the heater controls into and that running it can help put things right.

Also in the heater mode the fan speed should be slowest when first turned ON when the engine is cold, faster as the engine warms up and then slower again as the cabin temperature nears set-point.

Might be a temperature sensor related issue, with the heater controls constantly/immediately getting the signal that the engine is warm and cabin temperature is very cold.

[Jakw]

Oh no, the actual automatic control works fine, like it will turn down once the cabin is warm if I have it on auto, but once it does turn down, the fan stops blowing. In other words, fan speeds 1-3 don't blow ever, even if I manually select them. Is there a seperate blower/motor/whatever for fan speeds 1-3 and 4?

It isn't a huge deal, I'm just in one of those 'set everything the way it should be' moods, and it's annoying to have to futz with the climate control all the time when I know I don't have to if I fix it.

Btw, thanks for the quick reply dude.

[Rex]

Search for Darlington Resistor ... I think that's the culprit.

[GerryO]

I'm betting that the J30 climate control diagnostic mode is very similar to this and it's free! Running it could tell you something.

http://www.tamparacing.com/for....html
Modified by GerryO at 1:05 PM 1/8/2009

[Jakw]

Wouldn't the darlington make the fan blow all the time though? Such is not the case. I can make it blow high, or not at all. 1-3 = not at all. Automatic mode will put 1-4 on, depending on cabin temperature, but the fan still won't blow until level 4.

I'll check into that dignostic business, thanks.

[Rex]

Wouldn't the darlington make the fan blow all the time though? Such is not the case. I can make it blow high, or not at all. 1-3 = not at all. Automatic mode will put 1-4 on, depending on cabin temperature, but the fan still won't blow until level 4.

I'll check into that dignostic business, thanks.

http://www.q45.org/darlington.html

[GerryO]

It looks like voltage to the fan motor is stepped from 0V to 4V, 6V, 9V and finally 12V. Could be that the fan motor brushes are worn to the point where the fan won't turn unless it's getting 12V or that 12V means that some sort of variable resistor that is "open" is completely by-passed?

[yodawill2000]

Ive replace a few Darlington's in the past and that's the exact symptom

All or nothing.

[Jakw]

Ive replace a few Darlington's in the past and that's the exact symptom

All or nothing.

Alright dudes, I'll give that a shot first. Thanks.I'll go ahead and assume that it's in the same location in the J as it is in the Q then...yes?
Modified by Jakw at 6:55 PM 1/8/2009

[Jakw]

I can't find this part for sale really. I searched everythinginfiniti.com for a bit. Can someone link me please? It would be awesome...

[Infinitiguy19]

Hey I have one for $40 shipped from a Q45 if there the same and it works too.

[Jakw]

Potentially. I thought I read they were only like $60 from Scottsdale or something like that. I guess I'd rather buy a new one if these things wear out. Anyone know if they are the same part?

[nissanracer300zx]

You need a blower motor resister for the 1-3 fan speeds.

[yodawill2000]

That would be the Darlington resistor

[Jakw]

Yes yes, but where oh where can I buy one? Is it the same in any other Nissan/Infiniti vehicle?

[Infinitiguy19]

Just call IOS up.

[yodawill2000]

Or hit a salvage yard ..They usually don't fail unless the blower motor is pulling to much juice.Might look for both.

[Rex]

From the looks of things, it looks like a part you don't want to have to change more than once, if ever.

If you can get new from Infiniti of Scottsdale for $60, it might be worth only having to dig into the dash once??

Infiniti Of Scottsdale, (888) 216-5328, ask for Joe, say Wes sent you.

[Jakw]

Alright, thanks man.

Is the blower motor the same in any other Nissan/Infiniti? I want to grab one of those too, but I don't know of any J30s in salvage yards around here.

[Rex]

Alright, thanks man.

Is the blower motor the same in any other Nissan/Infiniti? I want to grab one of those too, but I don't know of any J30s in salvage yards around here.

I don't know, but Joe (or someone on his team) will be glad to tell you if the part #'s are the same across multiple models. Talking to them is one of the biggest benefits of calling.

[Victor]

Are you sure thats not a Darlington Transistor instead of resistor? If its a resistor you could go to any electronics supply place and buy some resistors of the same resistance and wattage as what Infiniti uses for probably less than a dollar apiece. You might have to do a little modification wiring if they mount differently.

http://en.wikipedia.org/wiki/Darlington_transistor

[Rex]

I believe the accurate term is Darlington Transistor, sorry if 'we" caused any confusion.

Here's a good link on cleaning the fan motor while you're in therehttp://forums.nicoclub.com/zerothread?id=262029

[Jakw]

Thanks for the info and the link, man. I'm on the phone with them now.

[Jakw]

Ive replace a few Darlington's in the past and that's the exact symptom

All or nothing.

So... behind the glove box looks sort of a lot different in the J than the pictures I've seen of Qs. I guess...what am I missing? I have the box off and that's as far as I've gotten.

[yodawill2000]

Sorry I mislead ya.Ive replaced many on other cars , Not my J.Surely somebody will chime in with the location.

[Jakw]

Found it. It's way to the back of the kick panel, mounted vertically. I don't think the glovebox even has to come out to get to it. I'll check it out and correct this post if I'm wrong.

[Jakw]

Alright, so here's what I learned.

-You just have to remove the passenger side kick panel, nothing else.-There is no metal rectangle. It's white plastic.-The plug that connects to the foot-area light on the kick panel connects to the Darlington assembly also.-The two bolts that hold it into place are 8mm.-This is one of those somewhat cramped jobs that will piss you off if it's cold outside because you'll keep dropping things.

[yodawill2000]

Good job ..I wont mention its in the 70's here. hehe Although it was 34 this AM..

Did it solve your Fan issue ??

[Rex]

Alright, so here's what I learned.

-You just have to remove the passenger side kick panel, nothing else.-There is no metal rectangle. It's white plastic.-The plug that connects to the foot-area light on the kick panel connects to the Darlington assembly also.-The two bolts that hold it into place are 8mm.-This is one of those somewhat cramped jobs that will piss you off if it's cold outside because you'll keep dropping things.

Just want to confirm, it fixed your problem?