This may sound like a silly question.........
......but do both cooling fans start when the A/C is switched on, and does their speed change in accordance with the refrigerant pressure?
If the refrigerant pressure (on the high pressure side of the compressor) exceeds approximately 1569 kPa, then the cooling fans should increase in speed.
If it exceeds 2648 kPa, the compressor will shut off.
If the fans are not running, or are running too slowly, then it is feasible that the refrigerant pressure will exceed this limit, and the compressor will shut off until it drops again.
................other than that, I have no idea what could be happening!
Jason.
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1992 Charcoal Grey SVX - 165,000km
1992 Ruby Red SVX - 165,000km
....now with sequential VIN numbers!
1986 Holden (Isuzu) Piazza Turbo - 225,000km
1993 Mercedes W140 S500 Coupe - 153,000km
1990 Mercedes W124 300D - 313,000km
EG33 + 4EAT + VTD AWD = SVX