Blow Motor-AC side works, but Economy side does not
#1
Member
Thread Starter
Join Date: Feb 2010
Posts: 121
Likes: 0
Received 4 Likes
on
4 Posts
Car: 1984 Trans Am
Engine: 305 L69 (E4ME)
Transmission: NWC T5 1352-072
Axle/Gears: 3.73 (6HS)
Blow Motor-AC side works, but Economy side does not
84 Trans Am. I was driving down the road with the heater on and the blow motor stopped working. The blow motor works under all the air conditioning settings, but when I move it over to the economy (vent, heater, defrost) settings, I only hear a click and the fan stops working. I put a test light on it, under the ac settings with the fan working the test light comes on, but it is a very dull light. When I move it over to economy the test light is very bright, but the fan stops moving. Any ideas what is causing this problem?
#2
Senior Member
Join Date: Mar 2009
Location: Des Moines, IA
Posts: 503
Likes: 0
Received 1 Like
on
1 Post
Car: 90 Formula WS6, 86 Sport Coupe
Engine: 305 TBI, 2.8 MPFI
Transmission: 700r4, 700r4w/vette servos
Axle/Gears: 2.73 Open, 3.42 Open
Re: Blow Motor-AC side works, but Economy side does not
Someone else will come along with a better answer but it sounds to me like the HVAC controls have just gone bad.
Good luck
Alex
Good luck
Alex
#3
Member
Thread Starter
Join Date: Feb 2010
Posts: 121
Likes: 0
Received 4 Likes
on
4 Posts
Car: 1984 Trans Am
Engine: 305 L69 (E4ME)
Transmission: NWC T5 1352-072
Axle/Gears: 3.73 (6HS)
Re: Blow Motor-AC side works, but Economy side does not
Turns out just a bad ground wire. I took off the black ground wire at the back of the blow motor. Then I hooked up a wire to the back of the blow motor and grounded it straight to the chassis and the fan started moving.
The strange part is that my fan has 4 speeds (Lo-Med-MedHi-Hi). On the AC side all 4 speeds work. On the Economy side, I'm only getting 3 speeds (Lo-Med-MedHi) to work no Hi speed. I swapped out the fan switch and the relay under the hood, but no luck.
It would seem strange to have it only work 3 speeds from the factory. Does everyone's heater (Economy side) work on all 4 speeds?
The strange part is that my fan has 4 speeds (Lo-Med-MedHi-Hi). On the AC side all 4 speeds work. On the Economy side, I'm only getting 3 speeds (Lo-Med-MedHi) to work no Hi speed. I swapped out the fan switch and the relay under the hood, but no luck.
It would seem strange to have it only work 3 speeds from the factory. Does everyone's heater (Economy side) work on all 4 speeds?
Thread
Thread Starter
Forum
Replies
Last Post
Ghettobird52
Tech / General Engine
15
12-29-2023 08:23 AM
Terrell351
Engine/Drivetrain/Suspension Parts for Sale
5
06-13-2021 01:13 PM