Mechanical Problems & Technical Chat If you've got a problem you just can't figure out, a noise you can't diagnose, or a check engine light that won't go away, ask about it here!

04 Civic. No air coming through vents.

Thread Tools
 
Search this Thread
 
  #1  
Old 02-05-2012, 06:30 AM
pensacolairish's Avatar
Junior Member
Thread Starter
Join Date: Aug 2010
Posts: 9
Default 04 Civic. No air coming through vents.

Hello folks, had the shop look at it yesterday and was informed it would be best to take it to the dealer. Said they tried a different blower motor and that wasn't the issue. Basically my problem is no air whatsoever, hot or cold flowing through the vents, as of from friday. Any idea what it might be, rough cost? I have no technical knowledge of cars I might add.
 
  #2  
Old 02-05-2012, 06:34 AM
mk378's Avatar
Recognized HCF Member
Join Date: Jun 2007
Posts: 10,023
Default

Usually the problem is the power transistor. With everything plugged in, turn key on and switch on high. Then measure voltage from each motor lead to ground.

Zero volts on both: No power from the fuse or relay. Those are both in the fuse box under the hood.
12 volts on one, zero on the other: The motor is getting power. If it doesn't run, bad motor.
12 volts on both: Bad power transistor or (very rarely) the control panel. There is a control panel self-test but I don't remember how to do it. If other functions of the panel work (you hear motors running when you turn the air selector), it's pretty safe to just replace the power transistor.

The power transistor is mounted to the ductwork behind the glove box. Some parts houses still call it a "blower resistor" even though it is actually a transistor in later models.
 

Last edited by mk378; 02-05-2012 at 06:38 AM.
  #3  
Old 02-06-2012, 05:00 PM
pensacolairish's Avatar
Junior Member
Thread Starter
Join Date: Aug 2010
Posts: 9
Default

Thanks mk, any idea of cost of repair/replace?

Originally Posted by mk378
Usually the problem is the power transistor. With everything plugged in, turn key on and switch on high. Then measure voltage from each motor lead to ground.

Zero volts on both: No power from the fuse or relay. Those are both in the fuse box under the hood.
12 volts on one, zero on the other: The motor is getting power. If it doesn't run, bad motor.
12 volts on both: Bad power transistor or (very rarely) the control panel. There is a control panel self-test but I don't remember how to do it. If other functions of the panel work (you hear motors running when you turn the air selector), it's pretty safe to just replace the power transistor.

The power transistor is mounted to the ductwork behind the glove box. Some parts houses still call it a "blower resistor" even though it is actually a transistor in later models.
 
  #4  
Old 02-06-2012, 06:22 PM
mk378's Avatar
Recognized HCF Member
Join Date: Jun 2007
Posts: 10,023
Default

The power transistor is somewhere between $50.00 and $75.00 for the part. Labor is minimal.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
sillysef
Mechanical Problems & Technical Chat
5
04-28-2011 03:51 PM
fawright
Mechanical Problems & Technical Chat
8
10-26-2010 04:04 AM
bko62
Mechanical Problems & Technical Chat
3
04-14-2008 06:34 AM
Accountant30339
Mechanical Problems & Technical Chat
19
09-12-2007 10:01 PM
Shandles
New Member Introductions
7
09-02-2005 04:05 PM



Quick Reply: 04 Civic. No air coming through vents.



All times are GMT -8. The time now is 09:36 PM.