Questions for the experts...

I realized that the newer MB cars need to have the Star Diagnostic System to scan and reset MB sub-system codes like Auto Climate, Central Lock,…

I like to DIY whenever possible with my 2003 SL500. Currently I have the AC-Off light stays on, which prevents the AC compressor clutch to engage. I like to be able turn it off so I can fix the AC myself.

I have recharged the AC and probed the AC compressor, and verified that the AC compressor is still working. I got the LOW and Hi pressure at about 27psi and 250psi when probing the AC compressor and the AC seems to work fine, and so far no indication of leaks.

I took out the evaporator temperature sensor verified that the ohm value changes when induced with various temperatures. I may eventually replace the receiver/drier, the evaporator temperature sensor, the expansion valve, the refrigerant pressure and temperature switch (by the way where I can buy this pressure/temperature switch beside going to the dealer?).

I have couple questions for the experts:

Will the AC-Off light automatically turn off once the AC system is corrected or a Star Diagnostic tool is needed to reset the fault codes or a manual procedure can be used to erase the fault codes?

If a Star Diagnostic tools is needed, where can I get the cheapest version that can be used to reset the AC related codes? Anything under $1000?

Also anyone in the Colorado Springs area owns a Star Diagnostic System can help out, please email me hxh_ym@yahoo.com

TIA, --Hung

The light staying on indicates a fault in the system. Scanning it, and retrieving codes, and then clearing them will often get it working again, unless there is a "hard fault". Any good independent shop that has an I-scan, Launch, or Auto Logic scanner can do it. --Z

Read these instructions and write down and then erase your codes. While on the error screen hold both auto buttons to erase each code. FF means no more codes. This may start the comp which will turn the EC light off which would then allow you to pull meaningful actual value data from the system.

http://www.eclassbenz.com/node/27

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)