No Heat!

[RJ-92]

My SHO has been without heat for a while. The car blows only cold air no matter where the temp dial is set. I have the manually controled HVAC system. My first instincts led me to believe it was the heater core. Well after removial of the whole dash there is nothing wrong with the heater core. No Leaks, and no blockage. It appears the perhaps the deflector door that regulates air flow over the heater core may be stuck in the closed position, allowing only unheated outside air to enter the passenger compartment. Is there any way to check where the problem my lie? Could it be the deflector door actuator motor, or possibly something else electrical?

The dash is completely outand I still have no way to figure out how to get my heat to work. Any help would be appreciated!

 

[projectSHO89]

First: Did you verify that both heater hoses were hot before pulling the dash, etc? This is a prerequisite for heat.

Secondly, the manual temp control moves a cable actuator that attaches to a lever on the temperature blend door. When the control **** is rotated, the lever opens and closes the door. When the door opens and closes, airflow is either through the heater core or is bypassed around the core.

Steve

 

[RJ-92]

No, I decided after I pulled the dash to check for warm heater hoses.


No cable actuator connected to the back of the control pannel. The temp control knobs look to be electrically controled. The air displacement (def, feet, pannel) are vacuum actuated. The motor that controls the temp door seem to be only connected to electrical wires.

 

[Ishodu]

Thy this.
http://www.shotimes.com/php-bin/modules.php?op=modload&name=News&file=article&mode=thread&

 

[Mr Anonymous]

It's April, who needs heat!?!? IIWM, I'd worry about it in about October...

 

[projectSHO89]

If it has the motor control for the blend door, you don't have a manual AC system as you indicated.

Your problem is either in the blend door actuator , the ETAC, or the fuse that supplies the motor (#17, iirc).

Steve

 

[Markus]

SHOooo:
It's April, who needs heat!?!? IIWM, I'd worry about it in about October...

Oh yeah? Monday night its supposed to be as cold as 12F here in Ottawa. oh_my

 

[Mark W]

To perhaps state the obvious, is the system full of coolant? That will cause it also. I didn't know it until a couple of years ago.

 

[RJ-92]

Upon further inspection there apears to be NO fuse in the 17 spot. HMMM, pull the dash for a fuse, that would suck.

The blend door is currently in the closed (full cold position), with the actuator connected the door is immovable. The actuator needs to be disconnected from it before it can me manually operated. Is this normal or should it be able to be moved? I don't believe the ETAC is bad. I guess it could be but I find it more likekly that it would be the blend door actuator.

Thanx everyone!

 

[projectSHO89]

You can "manually" run the motor by directly jumpering +12V and GROUND directly to the motor terminals. Reverse the polarity of the leads to reverse the direction of the motor's rotation. This is actually part of the diagnostic procedure of seeing if the BDA is defective. See the service manual.

So, where did F17 go to? How long since the beast had heat?

Steve

 

[RJ-92]

Well, its been without heat since last sept. I hae found the culpret to be a missing 15 amp fuse in the #17 spot. It seems I had removed the entire dash for nothing.

Now I have heat bet no taillights or parking lights! AARRGGHH....