Won't Blow !!

[fastblackcar]

A/c fan wont blow on high speed. I replaced the resistor, the relay and now finally the switch still no high, any help?, all other speeds work

 

[garyk1970]

my guess is the plug that goes to the high speed relay,check the terminal with the purple wire and clean with carb cleaner and a small pic(pay close attention,the details count for a solid connection) or whatever you have small enough to reach up in the terminal( becarefull not to spread terminals out so when you plug it back up it isnt tight)......even if it looks clean,clean it anyway . this is what was the cause of mine when i finally tracked it down....check all terminals at the resistor too,i remember now that these terminals were the same way(blue wire?) i believe,take your time,tedious work,buy very easy because of where these parts are on our cars....Gary

 

[topfuel]

Sounds like a wiring issue. I seem to remember a connector that gets hot
and melts. Pretty sure it's behind the radio somewhere, take a look in there
for a charred connector with a heavy guage wire in it.

 

[fastblackcar]

i checked the wires again, all wires look like new, with the switch on high, I unplug, replug the relay in the relay does click/ on ,still nothing, i will try to p/u some contact cleaner today, thanx everyone...........Tom

 

[onefastcar]

Same problem on mine check this thread out.
http://www.turbobuicks.com/forums/forumdisplay.php?f=8

How much volts on brown wire to head unit should be approx 12 if not a connector after that connects to two brown wires has a bad connection causing resistance need to change and yes its above the radio it will have to be removed and there is not much room to splice in a new connector good luck.

 

[garyk1970]

doesnt seem likely your main power cable is the cause by the symtoms ive read,clean terminals in the plugs mentioned (they get the most moisture,corrosion,etc since they are outside of cabin)before you start to dissasemble your car.....ive learned the hard way to check all the simple things first,then if no change, start checking the other items mentioned here in this thread...

 

[salvageV6]

Follow the fat red wire out of the shiny metal high speed fan blower relay over near the blower motor passenger side of the engine bay.

It goes over to a connector near the antenna in a wiring harness, the fat red wires just pass through the connector but usually get corroded or burnt there.

Power on that fat red wire is +12 at all times off a fusible link, so you can first test to make sure you have +12 at the metal high speed relay connector first if you want to.

Test however with IGN. key on and the blower motor on HIGH speed in the VENTS position on the A/C slider.

The ORANGE wire on that same high speed relay should have +12 on it as well on high speed with IGN key on in the vents position, this provides power to run the relay, black wire goes to a good ground to kick on the relay.

You should hear or feel it click if someone runs the blower motor switch from inside the car, key on, vents on, test, just go between medium and high with the fan switch to test the relay.

 

[BlackBandit]

I think nick het the nail on the head. Just check the purple wire connection. Wiggle it around and such.

 

[fastblackcar]

Thank you

thank you all who replied, for the first time my high speed works, i replaced the switch, resistor , relay, come to find out it was the connection btwn the fan and the fender, i have learned a valuable lesson, i ASSUMED since my wires all still looked like new, I couldn't have a connection trouble,WELL I was wrong to assume this, also after i realized the relay had no pwr on the red wire, i fixed the connection, and then still nothing i replaced the relay with my old one and it worked!!!!, GM sent me a bad relay !!!!!!!!!!! all is well now ...................thanx again everyone............Tom