I just joined this forum, after I was searching the web for answers to my problem (as outlined on another forum I've been on for years
A/C blower resistor now fails every four years, like clockwork). My wife's '98 GMC has a blower problem that I can't seem to fix, and I'm about ready to try and run a bypass directly to the blower, just so it'll work (I'm thinking of a variable potentiometer-controlled DC motor controller
PWM DC Motor Speed Controller, Brush Motor Driver Controls Module DC 9V-60V 12V 24V 36V 48V 60V Motor Pulse Width Modulator Regulator 20A).
I didn't know of this website, but I'm glad to be here. Sorry to revive an old thread, though.
Like the OP, I've replaced and/or tested all the components that blow air thru the vents: one blower motor, two resistors, and one control panel, and have the same recurring problem everytime I run the heater or A/C...the blower will either quit blowing, or decrease in volume/speed randomly, then I'll have to turn the A/C off (it's usually happening on very hot days, so a decrease in fan volume/speed is instantly noticeable) and back on, or hit the control panel with my fist, to get it back to normal...or not. Sometimes it just quits, then resumes 15 miles down the road, on its' own.
I'm tired of not being able to fix this problem after so many years, and no longer can easily work under the dash, at 73 with bad back & knees, so could anyone tell me which wires to tap into, without shorting the control panel?
I'm not so electrically-inclined, but I've wired up my old '66 Chevelle drag car (now gone) and wired-up many trailer brake controllers & electric radiator fans (including my latest project, a speed controller for my '01 BMW X5 project car
Done! Electric fan speed control...I'm not an electrician in any way, shape, or form), so I'm ready to bypass the panel if possible, just to see if it'll work.