No Heat"
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 834
Likes: 1
From: Keller Texas
No Heat"
I sent a message a couple of days ago about no heat coming out of the ducts. The air does come out of the correct place but cant get any heat. I checked it last night and it does have a flashing led light on the controler of the a/c. The a/c seems to work fine but I cant get it to work in the auto mode as well. It shuts off when both auto buttons are presed. I have only had this car for 1 month. Thanks for your help
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Are you saying when the controls are for heat you get none? I've heard of guys bypassing the heater because of the dreaded heater core needing replacement. I think you can check that in the engine bay.
Melting Slicks
Joined: Nov 2002
Posts: 2,471
Likes: 2
From: 1993 Quasar Blue 'vert Scottsdale AZ
I've had the same exact problem since I bought my '93. It's in the shop now for some warranty work. The heater is one of the things they are supposed to fix. I should get the car back tomorrow and I'll let you know what was wrong.
Drifting
Joined: Nov 2002
Posts: 1,593
Likes: 0
From: Mobile AL
St. Jude Donor '05
...while you're waiting for Lichen, check to make sure someone has not bypassed the heater core (two hoses under the hood should go to the firewall, one about 5/8" and one about 3/4" diameter).
Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
If you have a flashing LED sounds like you have electronic air. Press and hold both fan up/down buttons until --- appears then press the Auto button between them and read the codes.
DTCs are:
00 no faults
01 temperature door motor circuit fault
02 temperature door motore circuit fault
03 Ambient Sensor open
04 Ambient Sensor short
05 In vehicle temperature sensor open
06 In vehicle temperature sensor short
07 Solar load sensor open
09 Low freon
10 UART failure (this is the serial data from the CCM to the AC programmer.
DTCs are:
00 no faults
01 temperature door motor circuit fault
02 temperature door motore circuit fault
03 Ambient Sensor open
04 Ambient Sensor short
05 In vehicle temperature sensor open
06 In vehicle temperature sensor short
07 Solar load sensor open
09 Low freon
10 UART failure (this is the serial data from the CCM to the AC programmer.
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Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
no problem glad to help, once you get the code let us know and one of us can look at the DTC to see what is the specific fault isolation. BTW you keep pressing the Auto button to step through the DTC if there is more than one.
Melting Slicks
Joined: Nov 2002
Posts: 2,471
Likes: 2
From: 1993 Quasar Blue 'vert Scottsdale AZ
Sorry, I still might get my car back today, but the heater won't be fixed. The guy who does that kind of work for EM is gone for a couple of weeks. I you haven't found the problem by then, re-post and I'll let you know what the problem was.
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 834
Likes: 1
From: Keller Texas
Thanks for everyones help...........I did figure out that I have a temp. door motor circuit fault. so the code is 01. I checked it several times and that is it for sure. Any ideas now? What the h_ll does that mean? 
Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
Originally Posted by RED LT4
Thanks for everyones help...........I did figure out that I have a temp. door motor circuit fault. so the code is 01. I checked it several times and that is it for sure. Any ideas now? What the h_ll does that mean?
The A/C programmer logic will be lost if the A/C Prog and A/C clutch fuse or the negative battery cable are removed wih the ignition switch in the "On" position. The programmer logic will be restored by removing the negative battery cable and reinstalling after 1 minute.
The first an easiest test to eliminate the possibility of a false DTC being set is to remove the negative battery cable with the ignition "Off" and installing it after 1 minute. This will clear the programmer memory.
If the DTC returns you have a problem if not the system is ok.
If it did return it gets really technical and I believe it may require a Tech I or II to process diagnostics.
Last edited by 93JetJocky; Nov 19, 2004 at 10:19 PM.
Burning Brakes
Joined: Aug 2000
Posts: 1,052
Likes: 1
From: traveling nowhere fast, FL
I can see the blend door moving about a 1/4" in nonstop cycles. I could also move it to full heat so I can drive the car(still cycling). What do you guys think it is? blend door motor or the programmer that needs to be replaced? 
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
I'd guess the Programmer, as a 90 degree setting should override any input from outside/inside temp sensors, but make sure the linkage from the door isn't broken or loose and that there aren't any codes.
Burning Brakes
Joined: Aug 2000
Posts: 1,052
Likes: 1
From: traveling nowhere fast, FL
Kind of a gamble, spend $150 on a rebuilt controller and hope I don't have to pull out the heater box to get to the motor. Kind of weird how I can set the door at any postion and it just cycles away, back and forth 1/4"
