All sounds very political on here ...
I only wanted some advice.
Ive hooked up the OBDII to my test Diag and both Duo valves open and close independently allowing heat through or shutting it off, the clutch engages,
there was an error code relating to the Pulse module, however the crossfire doesnt have an intercooler plugged into slot E so im assuming that relay isnt used and thats the fault that wont clear, the other relay is the ignition.
Someone had sent me a MB bulletin relating to the same issue, that point to a collapsed suction hose on the compressor ? however the R170 320 SLK isnt mentioned on the list of effected vehicles.
The blower fan checks out ok on the diag as does the pump ...
The clutch does disengage every few minutes for a few seconds but on test it stays on ...
The garage is convinced its a stuck flap in the heater box behind the dash...
I thought my recirculate wasnt working but it is ...
The pressures on the ac are correct 35/40 on the low, I cant remember the high.
Last year it took two regasses to work properly, Ie i think it has a minor leak,
it was fine until may this year when it started to warm up.
On the 1st regas its was icy cold and lasted 3 days before going warm ...
The garage hooked it up and said it hadnt lost any gas but did a regen anyway, only this time it never got cold inside the car, only the pipes under the hood are cold, mainly the metal one that runs from the lo tap behind the headlight ...
The resistor does maybe need replacing but im told that has no bearing on the AC ... speeds on the blower fan are a bit funny, ..
Ive read the control unit for the ac in the car can have contact connection issues... .Ive also seen destructions on how to rectify this,

So in summery im at a loss ...

Im sorry for not doing a formal introduction ...
I have 24 years in the motor trade all in sales, I was also an account manager for the UK version of LoJack MB were one of my main dealer accounts so I still know a few people, but owing to the age of the car they dont really seem to have a clue, there is one seasoned tech in my local MB dealership who may have an idea but hes on holiday for the next 10 days ...