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ChrisFix
Is there anyway to get to a connector on the ventilation fan to apply 12V and determine if the fan is bad? The control panel fan indicator lights up (which runs off the same relay and fuse), but the fan doesn't run. I would like to determine if the fan is good or bad before removing the tank to get at it and was wondering if there is a way to do this.

Thanks!
McMark
Have you checked the switch behind the dash? That's usually the problem.
ChrisFix
QUOTE (McMark @ Mar 26 2005, 06:10 PM)
Have you checked the switch behind the dash? That's usually the problem.

I've looked to see that everything is connected correctly. I haven't checked for voltage at the various connections, which shoud be 12v? Any pointers on what to check specifically would be a great help.

Thanks.
McMark
Get on your back on the floorboards and undo the nut that holds the switch in place. (10 mm wrench) Then you can pull the switch mechanism out towards the back of the car. Clean the copper contacts really well. They're usually really dirty and cleaning them makes things work.
McMark
Here's the bolt.
Joe Ricard
You will have a hard time figuring out voltage at the switch. All you are doing is selecting a ground. 12V is applied on the red wire going into the fan.
You can gain access to it if you got REALLY small hands. pull the plug and you should be able to read 12V there.

While you are in there see if you can get the fan to spin by pushing it with anything other than a chopstick. dry.gif
Remove a hose use thin long screw driver reaching in either of the blower openings pushe the squire cage fan it should spin freely.
TheCabinetmaker
QUOTE (Joe Ricard @ Mar 26 2005, 08:23 PM)
While you are in there see if you can get the fan to spin by pushing it with anything other than a chopstick.

laugh.gif laugh.gif laugh.gif laugh.gif laugh.gif laugh.gif chairfall.gif
ChrisFix
So, after cleaning the switch contacts, everything works the same as before, which is the switch FAN light comes on when it should, but no fan.

The switch was actually pretty clean to begin with and all the connections are clean and tight.

Is there any test point to see if the fan is getting 12v without removing the gas tank to get to it? I just want to have some diagnostic to tell me that the fan needs to be replaced before having to go that route.

Thanks for all your suggestions.
McMark
Are you getting 12v at the switch? There is 1 feed wire for all three speeds. The selector just runs through a separate ground path.
ChrisFix
Hi Mark,

Is the power feed wire attached directly below the three "speed" wires as can be seen in your picture. I couldn't find 12v at the switch, but when I removed the feed wire, the "FAN" light would go out. I was guessing that it was just a ground supply because of that.

Is there a 12v source at the switch, or just grounds?
Rhodes71/914
Me too, Me too. I'd like to test my fan somehow without pulling the tank. Should have done it when I had the tank out for some other project.

Haven't put much effort into it other than cleaning the contacts on the switch. Still heater weather here so I haven't need it but I would like to get it working.
ChrisFix
icon_bump.gif
McMark...You still there...Where o where can I find 12v at the switch?
McMark
Okay, I read the wiring diagrams. 12v goes into the motor and grounds through one of the three wires. To test the motor, pull the three wires (arrowed) and connect each one to ground with a jumper wire. The door stay is usually a decent ground. Your motor should run three different speeds.
Joe Ricard
Red/white stripe is 12v it goes directly to the motor fed from fuse #9 any of the three white wires with either yellow, green stripe or all white are the grounds. The wire that Mark shows in the above picture also come form fuse #9 but only runs the light which you have said works. This proves fuse 9 is good.

Please try and spin the fan by hand. If it don't turn no reason to waste your time chasing power.

I would bet that you fan is stuck continuing to apply power to it will only burn the windings.
ChrisFix
QUOTE (Joe Ricard @ Mar 27 2005, 04:31 AM)
Red/white stripe is 12v it goes directly to the motor fed from fuse #9 any of the three white wires with either yellow, green stripe or all white are the grounds. The wire that Mark shows in the above picture also come form fuse #9 but only runs the light which you have said works. This proves fuse 9 is good.

Please try and spin the fan by hand. If it don't turn no reason to waste your time chasing power.

I would bet that you fan is stuck continuing to apply power to it will only burn the windings.

Thank you.

You're right. The fuse and power lead off the fuse are energized, so either the fan isn't getting ground (which I doubt as everything checks out as best I can tell) or the fan is either stuck, burned-out, or probably both.

I removed the air hose going to the right side of the air box (right side as facing it from the trunk, left/driver side of car) and could only see the air damper. Is the fan blade accessable if I probe deep enough from that side? huh.gif
McMark
QUOTE (Joe Ricard @ Mar 27 2005, 04:31 AM)
Red/white stripe is 12v it goes directly to the motor fed from fuse #9 any of the three white wires with either yellow, green stripe or all white are the grounds. The wire that Mark shows in the above picture also come form fuse #9 but only runs the light which you have said works. This proves fuse 9 is good.

Please try and spin the fan by hand. If it don't turn no reason to waste your time chasing power.

I would bet that you fan is stuck continuing to apply power to it will only burn the windings.

I wasn't pointing at the red/white wire. dry.gif
Joe Ricard
I Know you weren't point at the red/white wire (but it is the prdominent feature of the pic). I was just letting the guy know that this was not the power lead for the fan but only the indicator light.

Well I believe you are going to have to dive in. You can get into the plug area behind the fan housing if you remove the vapor can that surrounds the fill hole. I just did it to see if I could. Reached right back there and pulled the plug The power goes in on pin/socket number 1.
If the damper is in the way hopefully by moving the top selector lever on the dash you will actuate the dampers to open. If no movement of the dampers Step back have a beer. cause you are in for a long day.
PM me if you need to go further I can spell out the WHOLE Process.
McMark
Why pull the plug when three of those wires run directly to the ones I pointed at in my picture. wacko.gif

Obviously this has turned into miscommunication central. rolleyes.gif
ChrisFix
Mark and Joe,
Thanks to both of you.

You've given me the information I needed to understand how the fan control is set up which is a great help. I'm going to pull the expansion tank to get to the connector to satisfy myself that 1) the connector is seated fully and not just loose and 2) that 12v is actually making its way to there.

My guess at this point is that the fan is just shot, but one last test will let me know for sure if I need find a new one and tear the trunk apart to get to it.

I appreciate you taking the time to help me with this. clap.gif
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