'99 E320 A/C won't run - PeachParts Mercedes-Benz Forum

rjk · #1 04-24-2011, 04:18 PM

Daughter brings home car w/tale of woe, no a/c after winter.

Basic troubleshoot shows compressor not engaging.
Seems to have a charge but I do not have proper gauges.
Do not see where fuse is for compressor, not listed on any of the 3 fuse blocks.
I assume it is in-line somewhere?
EC button is lit and will not go out when button is pressed, bad switch or more ominous?
Compressor turns by hand.

Just for giggles, I checked duo-valve. Seems fine, no hang ups.

Anything else I can check before I take to a shop?
(A/C is about the only thing I farm out, hate doing it but no tools/equipment)

RichardM98 · #2 04-24-2011, 07:20 PM

Your CC Unit has built-in diagnostics. EC light almost but not always means a low charge.

Check this link for info on running diagnostics - http://www.eclassbenz.com/node/27

Best of luck.

rjk · #3 04-25-2011, 10:10 AM

Thanks, next time daughter is in town, I'll run error checks. Maybe even get her to do it!

RichardM98 · #4 04-25-2011, 11:13 AM

Be sure to write them down and also any error codes at the end. Sometimes a little 'interpretation' is necessary.

Good luck.

Gilly · #5 04-25-2011, 06:06 PM

Right, the EC buttom of course means "Economy", which is what you'd use to leave the compressor off. The EC light being on and not going off is a fail-safe by the ACC, sort of like being forced in to leaving the compressor off. So actually it's a "good" sign that the system is OK and yes the usuall problem is lowe on refrigerant charge.