After replacing the blower control module the A/C same as was
Thread Starter
Burning Brakes
Joined: Nov 2005
Posts: 1,211
Likes: 2
From: Dumas Arkansas
After replacing the blower control module the A/C same as was
I just installed the blower control module and when putting the fan speed on 10 it barely blows. Setting the fan speed on 5 is best for some reason. What else could be causing this? It doesn't matter if the temp's on 60 or 90 the blower speed is below average. Would it be the blower motor?
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Jumper the blower motor directly to the battery to make sure it works. Then measure input/output voltages at the Module. It's the tan wire and should be 2.5 volts at "1"; 6 volts at "10". Output, purple (or whatever color is hot at the blower), should be about 4 volts at "1"; 12 volts at "10". If the inputs are wrong, Programmer ('90 and above) may be at fault. You really need a Tech 2 or a bi directional scanner to figure it out. Signal is from the control panel over a serial data line. The right scanner can emulate the control panel and if the blower works the control panel is bad. If it doesn't, it's the Programmer. If you have an '89 or below, signal is directly from the Control Panel and if the voltages are wrong, you need a new Panel.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Bi-directional scanners - those that allow you to enter data via the CCM (linked to the Programmer) or PCM - can cost a small fortune. I'd check the input and output voltages to try and figure it out first. I think another member came up with something that allows you to get into the CCM and test the Programmer, but I can't remember whom. You might try a search.
Team Owner
Joined: Jan 2003
Posts: 20,333
Likes: 263
From: Summerland B.C. Canada
Heres my wacko way of thinking. If the bushings/bearings where worn out, would the rotor get pulled/pushed into the field magnet more during level 10 than level 5, thus allowing level 5 to be able to spin more freely. 
Thread Starter
Burning Brakes
Joined: Nov 2005
Posts: 1,211
Likes: 2
From: Dumas Arkansas
I held the up and down fan speed to get the codes and the code said it is the Vents? Can't remember which code number exactly but remember it was referring to the vents.
I got my test light but had trouble making it work. Only place I could make it light up was the battery. What's a good ground on these cars?
I got my test light but had trouble making it work. Only place I could make it light up was the battery. What's a good ground on these cars?
Team Owner
Joined: Jan 2003
Posts: 20,333
Likes: 263
From: Summerland B.C. Canada
Originally Posted by slicked25
I held the up and down fan speed to get the codes and the code said it is the Vents? Can't remember which code number exactly but remember it was referring to the vents.
I got my test light but had trouble making it work. Only place I could make it light up was the battery. What's a good ground on these cars?
I got my test light but had trouble making it work. Only place I could make it light up was the battery. What's a good ground on these cars?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Thread Starter
Burning Brakes
Joined: Nov 2005
Posts: 1,211
Likes: 2
From: Dumas Arkansas
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
That's simply the position commanded by the Programmer which opens and closes the vacuum ports which control the HVAC doors. The trouble codes are Mode 0 - System Faults. All of the other modes are nice but have little diagnostic value.
