AC blower fan resistor values

[Gopal]

Somewhere I read that they are 0.4, 0.8 and 1.5 ohms.

My 90's blower motor resistors were shot so I opened it to resolder. I checked the values. Turns out that the largest (or the thickest) coil had 0.8ohm and the the thinnest had 1.5ohms. It is the middle sized one that was burnt out and I cut out the burnt portion and resoldered it.

I am wondering if my readings were correct. Shouldn't the thickest have the least resistance of 0.4ohms?

BTW, this was the easiest of stuff that I've done so far

Thanks,
Gopal

[Gopal]

Someone...? Please?

Thanks,
Gopal

[Dave's]

My '91 truck was .4, .8, and 1.5 ohms. I'd be suprised if solder holds however. I figured it would take new ni-chrome wire.

[Gopal]

Dave,

Thanks for the reply. I know the solder will not hold.... hence I was wondering what should be the proper value of the resistor I need to replace. I have a nicrome wire available, but it not insulated. Is that a worry?

Gopal

[Dave's]

I know that many are now in a block of ceramic (???) but old one's are not insulated, they're just wrapped like around a pencil or something. Then pencil removed. You can probably find pictures on ebay. Just saw one for Toyota blower resistor which shows it with what looks like epoxy (JB weld) spread on it to reduce vibration. Regular resistors won't work. Can't handle the amps. Even tried a 5 amp and it started smoking. (Didn't try bigger ones, just got a salvage one and made one good unit from two.)

[Gopal]

Originally Posted by Dave's

I know that many are now in a block of ceramic (???) but old one's are not insulated, they're just wrapped like around a pencil or something. Then pencil removed. You can probably find pictures on ebay. Just saw one for Toyota blower resistor which shows it with what looks like epoxy (JB weld) spread on it to reduce vibration. Regular resistors won't work. Can't handle the amps. Even tried a 5 amp and it started smoking. (Didn't try bigger ones, just got a salvage one and made one good unit from two.)

Ah! So the white thingy spread over the resitor is meant to be there! I cleaned it out think it to be a melt of something. . Now I need to put it back. I hope JBWeld works.

I did think about putting a regular resistor, but decided against it because of the reason you mention. Well, I will fetch out my Ni-Chrome - finally some real use for it . I forget why I had bought it in the first place...

[88 LE]

http://www.greenhydrant.com/~drees/a...ry/faq.php#fan

You can use ceramic wirewound resistors.

[Gopal]

Originally Posted by 88 LE

http://www.greenhydrant.com/~drees/auto/camry/faq.php#fan

You can use ceramic wirewound resistors.

Thanks 88LE.

I will change all 3 next time. What is the configuration? I checked the resitances, the largest showed .8ohms, and smallest one was 1.5. The middle one was burnt. Should that be the 0.4ohms?

Gopal

[88 LE]

^ Seems logical to me.

Theres 3 resistors. 0.4, 0.8, and 1.5.

[Gopal]

For some reason I thought the gauge of the wire determined the resistance...

Will let you know how it went...

Thanks,
Gopal

[88 LE]

http://toyotanation.com/forum/t62289.html

Now that I go back and look at my pics in the thread above, I'm not so sure anymore.

I was going off what you measured and said. Sorry about that.




http://www.greenhydrant.com/%7Edrees...ry/faq.php#fan

^ This says:

If you look at the pack from left to right, and call them resistors 1, 2, and 3.

the factory Camry electrical wiring manual lists the resistors as 0.4, 0.8, and 1.5 ohm for 1-3 respectively.

So the one in the middle is 0.8 ohm. The other 2 are 0.4 or 1.5.




Looking in my EWD manual, it says this:

1-2: Approx. 1.2 ohms
1-5: Approx. 3.7 ohms
2-6: Approx. 0.4 ohms


The pin numbers (1-2, 1-5, 2-6) are looking at the end of the plug. End where it plugs into the resistor pack, not where the wires go in.

Pin numbers:

1, 2, 3
4, 5, 6

3 and 4 are blank. In other words no wires in those spots.



So looking at the resistor pack its:

3, 2, 1
6, 5, 4






Manual shows a different plug (4 pin) for the lever type ac/heater controls.

The specs say:

1-2: Approx. 1.5 ohm
2-4: Approx. 0.8 ohm
3-4: Approx. 0.4 ohm


Pin numbers:

1,2
3,4


Looking at the resistor pack its:

2,1
4,3

[Dave's]

That's some great info 88 LE! I tried those ceramic wirewounds but they were only 5 watt and started to fry. They make larger ones but fit becomes a problem. Ni-chrome does come in different resistances per lenght. Which was why I didn't go that way. 3 rolls and the cost was too great.
Let us know how it goes.

[Gopal]

88LE, Thanks!

That's a nice piece of information to have. I checked at the wires and not at the pins - I don't know what was I thinking! Actually, I had to scratch some solder off to reach a clean surface for measurement (and ofcourse to solder back the middle one).

I am having some difficulty to correlate your diagram and the resitor-side view.

But I think this is how it went... (hope my recollection is correct). I will confirm back again later...

321
654

I measured between
3-6 : 0.8 ohms
1-4 : 1.5 ohms (approx) The reading was bouncing a bit.

The middle sized wire was between 5-4, with about 0.8ohms when I soldered it back.

I am going the Ni-chrome route. I found that about an inch long piece gives me the required 0.4 ohm resistance. I am planning to use JBWeld for keeping them apart/insulation. Any opinions on this?

Dave, I'll surely post once I put it all together...

Thanks again!

[88 LE]

Originally Posted by Gopal

I am having some difficulty to correlate your diagram and the resitor-side view.

But I think this is how it went... (hope my recollection is correct). I will confirm back again later...

321
654

Sounds right, but thats looking at the front of the resistor pack. In other words the side where the wiring plugs in.

If your looking at the back (where the resistors are soldered on) of the resistor pack, the pin numbers are obviously backwards.