hemmerman

Just bought a 1999 C5 coupe. The air works great but, it throws hot air out of the two passenger side air ducts. What's going on?

egrand333

Duel climate control? Search "actuator"

hemmerman

yes it's a dual climate control system. cold air coming out of drivers side ducks and hot air out the passenger side

meanjoe

I also have a 1999, Duel controls, There is a vacuum controled door behind the dash that controls all that. They had to remove the entire dashboard to replace it. While your under there you should also replace the evaporator coil and heater core so you never have to go under there again. It's not a pretty sight. I can send pic's if you like. Unless your very handy with tools....... The dealer quoted me $4.5-5K that was with all new parts compressor, condenser, evap coil, not including blender your having trouble with or the heater core. I got a good local shop I always use to do it for 3500.00 everything.
At least the car blows real cool now.
Good luck

molten vett

Start with a simple check of your Freon. I noticed once when my Freon was low I would get cold air on passenger side a hot air on drivers side,added the proper amount and the problem went away.

Bill Curlee

Well lets start even simpler. Read and post your DTCs and lets see what is really happening.

READING YOUR Engine Diagnostic Trouble Codes (DTC)

This procedure should be carried out any time you experience a problem with your C5. Most inexpensive store bought aftermarket code readers will ONLY read power train DTC’s. Reading the DTC’s with the C5 built in code reader will allow you to read ALL the modules in the vehicle.

The Diagnostic Display Mode is entered with the following procedure:
1) Turn on the ignition but don't start the engine.
2) Press the RESET button to turn off any warning messages. (i.e. door open, trunk open ect)
3) Press and hold the OPTIONS button
4) While holding OPTIONS, press FUEL button four times within a 10 -second period.

Initially, the on-board diagnostics go into an Automatic Mode which will cycle through each module and shows diagnostic codes in a pre-set sequence: PCM - TCS - RTD - BCM - IPC - RADIO - HVAC - LDCM - RDCM - SCM - RFA. All codes will be displayed for each module. ( i.e. PCM = 4 codes) If none are present in a given module, you will see No More Codes on the display.

There are two types of diagnostic codes, Current and History designated with a letter suffix, “C” or “H”. A current code indicates a malfunction is present in the module displaying data. A history code indicates a problem existed sometime in the last 40 or 50 ignition cycles. When not accompanied by a current code of the same number, it's potential evidence of a previous problem, now resolved, that was not removed by clearing the codes. More likely it's an indication of an intermittent malfunction.

Intermittent codes are the most challenging of the diagnostics. An intermittent code may have happened once, may have happened more than once but is inconsistent or may be happening on a regular basis but not at the time the codes are displayed. History codes can also be caused by a current malfunction in a system that is not operating at the time codes are displayed. An example is the rear window defogger which doesn't operate until the Body Control Module detects engine rpm. For history codes set by a module that does not operate with the key on and engine off, a special diagnostic tool called a Scan Tester is necessary to properly diagnose the malfunction.

Once the system has displayed all modules, it goes into the manual mode which allows selection of each module using combinations of Driver Information Center buttons. Manual mode can also be entered during the automatic sequence by pressing any button except E/M. Once the display shows Manual Diagnostics, select a module by pressing the OPTIONS button to go forward or the TRIP button to go back. Once a module is selected, a code is displayed, and if more than one are present; press GAGES to go forward or FUEL to go back.
To exit the diagnostic mode at any time, press E/M. If you want to erase codes in a given module, press RESET To reset the codes once in manual mode, press and hold RESET until it displays NO CODES Press OPTIONS to go to the next module. Repeat the steps until you have reset the codes in all the computer modules.
NOTE!! Only reset the codes IF you want to - it is NOT necessary to do this. Clearing a code does not repair a problem. You are simply erasing the evidence of it in the module's memory. If you clear the code/s, and extinguish the Check Engine Light, your emissions status ready will NOT allow you to pass an emissions test until you have completed the required driving cycles. There are a few body module DTC’s that if set will prevent the module from operating properly. Once the DTC is cleared, the module will return to full function. This is not true for power train DTCs.

If you have never read and cleared your codes, there will probably be a lot of old history DTCs. It is recommended that you clear your codes and see if any come back during a driving cycle. Those are the ones that you need to concentrate on diagnosing.

Once you have the codes, the next question is: What to do with the information?
First, consult the factory service manual. Any serious C5 Do-It-Yourself owner should invest in the Corvette Service Manual of the appropriate model year. The Service Manual is really a requirement if you want to understand and work on your C5.

You can read the DTCs while the engine is running. If you turn the engine OFF and then back ON, that can clear some DTCs that may be important with identifying a problem. One example is a Misfire DTC (p-0300) If the engine is shut down, the DTC will clear.

These are some very good C5 Diagnostic Trouble Code (DTC) explanation web sites!!! They also explain how to read the DTCs

Here is a very good PDF on DTCs and what they relate to:

http://forums.corvetteforum.com/c5-t...odes-dtcs.html


Here are some very good sites that explain what DTC mean:

http://www.gearchatter.com/index10.php

http://www.obd-codes.com/


*** Make sure to include the H or C suffix when you post your DTCs!! They are important!!!

Updated 13 September 2012 :-D

scott1974

Add freon. Seriously.

cdkcorvette7

Probably this, but follow Bill's advice above and post your DTC's. No need to guess...

Trios

Do you have your ducks in a row? Ducks that are following without being in a proper row could cause this issue. Be sure that all the ducks quack properly as well; usually picking up the duck (say, to place it back into the row) should cause a quack and you can tell if its quacker is still good.

whitesmokels1

This has to be the funniest thing I've read in a long time!

Bill Curlee

The vacuum controls WHERE the air comes out. It allows you to switch from the lower floor vents to the CENTER VENTS and to the DEFROST. It also controls if you open or shut the door that recirculates or brings in outside air.

Here is a VACUUM ACTUATOR:




All the temperature controls are accomplished by TEMPERATURE DOOR ELECTRIC ACTUATORS



If you have an electric actuator issue, it will show up as a HVAC DTC

Trios

No mention of ducks, Bill? I already solved his issue above. I'm sure you must've just missed it.

hemmerman

thank you for your help

cdkcorvette7

codes?

hemmerman

this is my first time at bring up the codes. I've got the instructions. As soon as I do that I'll post them. Thanks again.

meanjoe

Yeah
Thats what I thought. Everything should be that easy

meanjoe

I prefer my ducks in a zig zag pattern