I have a tale of woe that has cost me over $700.00 with no cure so far? I hope the expertise out there can help? I imported from Germany a 300 CE Sportline. My AC works for about 5 - 10 minutes and then quits. Recently my ASD (Differential Sensor) warning light has come on as well. I have also noticed that on occassions the speedometer jumps from 0 to the speed I am currently travelling. I have the following questions:

1 Could these problems be connected?
2 Can I still drive with the ASD warning light on?
3 Where can I purchase a service manual with wiring diagrams etc?
4 If its a relay switch how can I tell?
5 Any idea where the AC relay switches are?

I would be forever in debt to anyone who can give a British soldier in Canada, who has little or no mechanical knowledge some ideas?