Hi Everyone,

My car, 99 E300TD, vent system is not working and I need some advice on how to troubleshoot it. When I put on the AC, one side is very cold and the other just blows air, neither hot or cold.

What should I start looking at?

Thank you for your help.

Either a bad duovalve, or if the cold side is on the right, low refrigerant flow due to low refrigerant level or a restriction.

Thank you for the response. Where is the duovalve? So is there 2 separate AC systems in this car or is there 1 that is getting split?

Thank you.

As matt said, if the cold side is the right side it is usually a low charge. There is one A/C system but the heat is broken into two sides so you can have one side of the heater core hot and the other side cold if the duo-valve is open for that side. I'd bet you have a low charge though. Do you hear hissing in the dash when the A/C is running? If you want to get into diagnosing it read this excellent article:

http://www.continentalimports.com/ser_ic40142.html

Scroll down to A/C diagnostics heading and dig in!

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

Yes, the right side is cold. I do hear a hissing but it is right right after I accelerate. I also hear some hissing like noise at other times.

Great link!!! I will troubleshoot my system and report back.

Thank you!!!

Based on the instructions from the link, here is what I found:

EB! 419
E FF

2 - hi/lo fails

So from this thread:
http://www.peachparts.com/shopforum/showthread.php?t=126024&highlight=diagnostic+trouble+code+419

419 A/C Compressor Electromagnetic Clutch (A9k1)

I do not know what FF means. Does anyone know?

Thank you.

FF means "end of codes."

EB1419 looks to be a red herring, since you do have some cooling.

Hissing while running (as opposed to just upon startup) means low refrigerant flow. This cause the warm left side as well.

I would highly recommend against using a cheap refill kit with only a (very inaccurate) low-side gauge. If you refill it yourself, get a real gauge set so you can monitor the high-side pressure. If you have a restriction between the compressor and dryer outlet, the gauge will read high and you can shut it down before damage occurs. If all is normal, the high-side gauge will agree with the climate-control pushbutton unit.

In any case, if you attempt to refill it yourself, be SURE to purge the recharging equipment hoses of air. Don't inject a load of air in there.

Avoid o-ring conditioners or ANY leak sealers. These do more harm than good.

Hi Matt,

Thank you for the advice. I'll get a AC person to charge it.

Do you know of a way to reset the codes?

Thank you.

To reset the codes, first read them all out again. Then hold both AUTO buttons for >2 seconds, until the display changes. Then turn the key to position 0. To cancel the reset, press one AUTO button before turning the key.

Recharged the AC today and it was so cold I had the turn the temps up and it was 101 here!!

THANK YOU FOR YOUR HELP!!!!