Blower speeds. Any advice

[blacksambo]

My wife's '99 blower fan is only operating on high, the other three speeds are dead, and the fuse is good. I think it's the fan resistor that needs replacing? Any ideas out there? Many thanks.

[JULIAN911]

Yes it's the resistor. Do a search and you'll find plenty of how-to's

[tom4bren]

Here's a thread you need to read (& there's a hyperlink to another in there).

http://www.vehicross.info/forums/sho...lower+resistor

[blacksambo]

Thanks for the guidance, I'll get a new resisitor.

[tom4bren]

After you get the new one, you should try to fix the old one (just to keep it as a spare). It sounds fairly simple.

[ZEUS]

blacksambo, you've received only partial info on this issue. Before you get a new resistor make sure you do some other things...

There are two fuses to check, sounds like you checked at least one, just make sure you check the other if you haven't.

Also, think about what caused the resistor to give out. Before you order one, get into the dash and blower housing to check things out.

Resoldering the unit is very easy and it's free.

When the blower quit working on my '99, I checked the fuses (one bad), checked the motor itself (good), resoldered the (bad) resistor, put things back together... and nothing... Took the resistor back out and it was fine so I checked the fuses again and the same one under the hood had blown again. The culprit ended up being the HVAC control panel... grease is used to keep the levers moving freely, in time these accumulate quite a bit of dust and what-not. I simply moved the switch back and forth quickly several times and sure enough, I haven't had a problem since! So the faulty switch caused the fuse to blow consistently and the resistor to fail once... apparently.

This is the thread I used to find my way: http://www.vehicross.info/forums/sho...lower+resistor

[tom4bren]

Zeus,

I thought it was you who had fought that battle a while back. I wasn't sure tho so I kept my mouth shut (didn't want a lightning bolt dropped down my shorts). Wait ... I got it anyway.

[ZEUS]

Always and forever... you know you like it.

[blacksambo]

Thanks for the link. Very helpful. My blower runs fine in position #4 so the resistor sounds like the culprit. They cost $50.80, so I ordered one from my Isuzu dealer, it will be in on Friday.

[circmand]

My wife's '99 blower fan is only operating on high, the other three speeds are dead, and the fuse is good. I think it's the fan resistor that needs replacing? Any ideas out there? Many thanks.

Y/M/M is your wife?

[samneil2000]

Thanks for the link. Very helpful. My blower runs fine in position #4 so the resistor sounds like the culprit. They cost $50.80, so I ordered one from my Isuzu dealer, it will be in on Friday.

Oh man, it's awesome to see someone post a thread of mine to help someone else.
You coulda saved 50 bucks blacksambo! Ship me your bad resistor and the 50 bucks and I'll send you your resistor back fixed. haha, JK, unless you're willing. haha

[Moncha]

Y/M/M is your wife?

[blacksambo]

New resistor is in place works fine. Thanks for the repair offer but needed it done quick. (By the way, the resistors say do not repair on them. Maybe they know something we don't know?)

[tom4bren]

"(By the way, the resistors say do not repair on them. Maybe they know something we don't know?)"

Yup ... they make more money selling you a new one rather than telling you to fix your old one.

[PK]

New resistor is in place works fine. Thanks for the repair offer but needed it done quick. (By the way, the resistors say do not repair on them. Maybe they know something we don't know?)

I might be talking through my arfes here, but I think the repair is to re-solder contacts that have separated.
Being a resistor, they create heat, and the original unit could be assembled with a special solder that gives a thermal overload protection.
This is achieved by using a special alloy solder that melts at a known temperature.
If you do the repair with standard solder, you loose the thermal overload protection.
We use this method to provide automatic closing of fire dampers in ships.
It is called a "thermal fuse" or "fusable link".

of course, I might be totally wrong in this case.
Perhaps Deermagnet, or one of the electronic gurus will speak up.

PK