3800 Did you Know?

[Toasty]

Did you know that a bad blower motor resistor pack CAN cause hi/5 to stop working? back between november and january, i progresssively lost a blower setting, resulting in only having high setting since january. been using the fan on high ever since, hadnt gotten around to changing the resistor. then today, blam! the fan just stopped. no noises, etc. i freaked a little, thinking that the wiring or the motor was toast.

check fuse in block, good.
check for power across fuse in block, good
spend more time than i care to remember on my back removing blower motor and resistor pack.
rig up wiring to test blower from underhood. blower motor good. PHEW!
alright. check wiring harness leads for power at fused power and full on/high... good power... HALELUJA
so i sat down with the multimeter and the old resistor, and checked continuity, and didnt find good things.
$25 bucks later to auto-stone and i'm on the way home with a new resistor. continuity testing better on that one.
plug everything in temporarily, check fan speeds...YAY! FIXED!
so then spend more time than i care to remember getting the pieces back together.
go inside. drink dew. life's better.


yay!

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[Royalgtp]

very common to lose a speed or two for the blower motor.

 

[Toasty]

very common to lose a speed or two for the blower motor.
[/b]

yeah i know it's common to loose a speed or two from 1-4. but i've never seen reference to loosing the high/#5 since it technically bypasses the resistors in the pack.... i guess the moral of the story is, once you start loosing speeds, replace the thing before they all go. 90+ degree heat with no blower is teh suck!

 

[Turbocharged400sbc]

nice work! i wouldnt think it would affect the high speed fan relay either....unless your high speed fan relay's contacts are carboned up from constant high speed use...with the relay energized what is the secondary side open?

 

[smug]

my resistor screwed up and i lost setting 1, then setting 5 stayed on when i shut the car off so i pulled the fuse for the blower and got a new resistor. Everything worked as it should after that.

my resistor screwed up and i lost setting 1, then setting 5 stayed on when i shut the car off so i pulled the fuse for the blower and got a new resistor. Everything worked as it should after that.

 

[Royalgtp]

Yeah, usually the highest speed will still work....

 

[Toasty]

nice work! i wouldnt think it would affect the high speed fan relay either....unless your high speed fan relay's contacts are carboned up from constant high speed use...with the relay energized what is the secondary side open?
[/b]

i didnt actually test the old pack with it energized, rather tested continuity from the input pins out to the leads that go to the blower. it was kinda odd. i got no continuity on the fused battery feed line, but did get continuity to the high/#5 switch setting. i didnt really bother checking the other speeds, since it was obvious that those resistors were gone. From what I gather, the resistor pack failed as per usual, leaving the high speed setting OK since that one bypasses the resistor network. what failed was the fused battery input pin/lead in the unit.

haha, i was quite proud of myself... i havent had any real excuse to use my new multimeter that i got for christmas

 

[framos242]

I need to change my blower motor resistor this weekend.

 

[Toasty]

I need to change my blower motor resistor this weekend.
[/b]

find your 7/32nd socket, and some advil.