my car has a small issue i cant seem to find the fix for. seems a mode door or vacuum line is messed up for the heater/ac/ventilation system. the ac blows warm, but the compressor is coming on properly, the AC lines undr the hood get cold like they are supposed to, the drain drips condensation like its supposed to, basically what im seeing is the middle ****- non auto climate car by the way- that conrtols temp doesnt close whatever door it needs to to shut off the hot air and open the cold air. before i start disassembling the car, i was hopin for some guidlines. ive worked on these vacuum/cable driven systems before in my old chevy and on my little neon but these cars always seem to be designed screwy. anyone able ot shed light?

 

Check here....

http://vette.the-reeds.com/actuator/actuator.htm

 

Are you getting any HVAC codes? Have you pulled off the intake manifold and not reattach the small vacuum line? Is the battery leaking onto wires and vacuum lines below it?

 

no leaks from battery, just replaced it and it was and still is fine. havent done any motor work at all, ill check to make sure no vacuum lines are off, is it in a place that might have gotten knocked loose during one of my overzealous engine detailing sessions? ill ck HVAC codes when i get home.

 

hahaha. no codes in my car. manual AC doesnt store HVAC codes. neat. learn something new every day. i did as the above link suggested anyway to see if i could see in there and took it apart but mine being a non auto climate car doesnt have that actuator gizmo. any other suggestions?

 

I know alot of the vaccume lines for the HVAC system run under the battery. It's possible that a battery had leaked before and ate some of them. You'll have to pull the front passenger tire and remove the inner fender plastic surround or trim. That will give you access to the PCM and the vaccume lines. I'll check and see if I have a pic of the area...

 

This one has some pics…

http://forums.corvetteforum.com/show....php?t=1422586

This is another good one…

http://forums.corvetteforum.com/show....php?t=1425037

 

Here is the diagnostic for an inoperative temp control on a manual air car:
Temperature Control Inoperative
Temperature Control Inoperative <<C60>> Step
Action
Value(s)
Yes
No

1
Has the HVAC Diagnostic System Check been performed?
--
Go to Step 2
Go to Diagnostic System Check

2
Were you sent here for a poor cooling concern of the passenger compartment?
--
Go to Step 3
Go to Step 4

3
Does the A/C compressor clutch engage when the A/C button is depressed?
--
Go to Step 5
Go to HVAC Compressor Clutch Does Not Engage

4
Before proceeding with this table, verify the following conditions:

the engine is reaching normal operating temperature.
both upper and lower radiator hoses have become hot.
both inlet and outlet heater hoses have become hot.
the cooling system is operating normally.
Is the cooling system operating normally?
--
Go to Step 5
Go to Heating Insufficient

5
Disconnect the temperature door motor connector.
Turn the ignition switch to the ON position.
Connect a test light between terminal 10 of the temperature door motor connector and a known good ground.
Does the test light illuminate?
--
Go to Step 9
Go to Step 6

6
Inspect the HVAC MiniFuse® #18 for an open circuit.

Is the fuse open?
--
Go to Step 8
Go to Step 7

7
Locate and repair an open or a high resistance in CKT 41.

Is the repair complete?
--
Go to Step 18
--

8
Locate and repair a short to ground in CKT 41.

Is the repair complete?
--
Go to Step 18
--

9
Connect the DMM between ground and terminal 7 of the temperature door motor connector.
Measure CKT 150 for continuity to ground.
Is CKT 150 continuous to ground?
--
Go to Step 11
Go to Step 10

10
Locate and repair an open or a high resistance in CKT 150 between the temperature door motor connector and G201.

Is the repair complete?
--
Go to Step 18
--

11
Connect the DMM between terminal 8 of the temperature door motor connector and a known good ground.
Turn the ignition switch to the ON position.
Turn the temperature control **** from hot to cold, and cold to hot.
Does the voltage vary within the specified values?
1.0-12.0V
Go to Step 12
Go to Step 13

12
Check for a poor connection at the temperature door motor.
Check for a binding air temperature valve.
If OK, replace the temperature door motor.
Is the repair complete?
--
Go to Step 18
--

13
Turn the ignition switch to the OFF position.
Disconnect the HVAC Control Assembly connector C1.
Connect the DMM between terminal 8 of the temperature door motor connector and a known good ground.
Measure CKT 1316 for continuity to ground.
Is CKT 1316 continuous to ground?
--
Go to Step 14
Go to Step 15

14
Locate and repair a short to ground in CKT 1316.

Is the repair complete?
--
Go to Step 18
--

15
Connect the DMM between the temperature door motor connector terminal 8 and the HVAC Control Assembly connector C1 terminal G.
Measure CKT 1316 for continuity between these two connectors.
Is CKT 1316 continuous between the temperature door motor connector terminal 8 and the HVAC Control Assembly connector C1 terminal G?
--
Go to Step 16
Go to Step 17

16
Replace the HVAC Control Assembly.

Refer to Control Assembly Replacement .

Is the repair complete?
--
Go to Step 18
--

17
Locate and repair an open or a high resistance in CKT 1316.

Is the repair complete?
--
Go to Step 18
--

18
Install componets or connectors which were removed or disconnected.
Operate the system in order to verify the repair.
Did you correct the condition?
--
System OK
Go to Diagnostic System Check

Bill