No heat, no A/C, no defrost,
02-23-2015, 07:22 PM
#1
7th Gear
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No heat, no A/C, no defrost,
I've been trying to diagnose this for a week now. I searched but nobody seems to have the exact same problem.
I lost everything all at once. When I turn on heat, a/c, or defrost nothing happens. No noise of a fan blowing at all. I removed the blower fan & tried putting in another from Advance, nothing at all. So AC Delco unit in car, fan not blowing, generic, same problem. I think it might be a fuse or power source of some sort. Is it a fuse I need to check or is more complicated than that. I hate to take it to a mechanic & pay labor but I'm lost.
Anyone else have this problem? Car is a '98 with auto climate controls if that helps. Thanks.
I lost everything all at once. When I turn on heat, a/c, or defrost nothing happens. No noise of a fan blowing at all. I removed the blower fan & tried putting in another from Advance, nothing at all. So AC Delco unit in car, fan not blowing, generic, same problem. I think it might be a fuse or power source of some sort. Is it a fuse I need to check or is more complicated than that. I hate to take it to a mechanic & pay labor but I'm lost.
Anyone else have this problem? Car is a '98 with auto climate controls if that helps. Thanks.
02-23-2015, 07:44 PM
#2
Burning Brakes
Seems like if you lost it so quickly, the first thing would be to check the fuses, and the easiest. Check under the passenger for fuse 52-blower motor, it may be under fuse cover for the numbers , if not, do a search and get a free owners manual to help. Once you locate it, you can probably trade out a similar fuse to see if it works, if it does, you've got it. Good Luck
02-25-2015, 03:12 PM
#5
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
The HVAC control unit feed its CONTROL SIGNALS to the FAN CONTROLLER. That controller is mounted on the under side of the HVAC AIR BOX (just to the left of that FAN you replaced.
Its a black box that connects to the main harness and the FAN pig tail plugs into it.
They are WELL KNOWN to go bad. YES,, They are expensive to replace.
Pop it out and take the box apart See if the circuit board has melted foil traces and or blown components:
Bill
Its a black box that connects to the main harness and the FAN pig tail plugs into it.
They are WELL KNOWN to go bad. YES,, They are expensive to replace.
Pop it out and take the box apart See if the circuit board has melted foil traces and or blown components:
Bill
02-26-2015, 01:33 PM
#6
Instructor
Bill, is the fix as simple as soldering a piggy back wire along side the damaged trace or is there an underlying cause that needs addressing before the repair?
02-27-2015, 08:04 AM
#7
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
Well,,,,, Most of the time something causes the module to draw more current than it suppose to handle so,, that trace smokes.
I have one that smoked and didnt see any root cause just by eye balling it. It was given to me so, I have yet to mess with it. Give it a try and see what happens.
Bill
I have one that smoked and didnt see any root cause just by eye balling it. It was given to me so, I have yet to mess with it. Give it a try and see what happens.
Bill