B. A/C Compressor Does Not Switch on

No refrigerant visible through sight glass.








1. Connect suction/discharge gauge (19, Figure 2) of A/C service tester to service valves on A/C system (Figure 3).





2. Start engine and engage the A/C system from pushbutton control panel.

Note:
To confirm that the refrigerant low pressure switch (S31) caused the compressor to shut-off, briefly bridge the terminals of the low pressure switch. If A/C compressor clutch still does not engage, check electrical system.

3. If a suction/discharge pressure above 4 bar is obtained, test the A/C compressor engagement according to the instructions on the respective service microfiche, job no. 83-040.

4. If a suction/discharge pressure below 2 bar is obtained, charge the system with 200 g refrigerant R12 and check for leaks. If a leak is found on the compressor or condenser lines, the compressor must be tested as outlined in section C prior to the exchange of the leaking parts.

Note:
When charging a system, the refrigerant capacities (shown in the table) supersede all others.

5. If a suction pressure below 0 bar is obtained, replace the expansion valve.