The present invention relates to a motor vehicle thermal management circuit (1) comprising a refrigerant loop (A) through which a refrigerant circulates, the said refrigerant loop (A) comprising: a first compressor (3), a first heat exchanger (5), a second compressor (7), a second heat exchanger (9), a first expansion device (21), a third heat exchanger (11), the said refrigerant loop (A) furthercomprising a bypass leg (B) connecting the refrigerant outlet of the second heat exchanger (9) to the refrigerant inlet of the first heat exchanger (5), the said bypass leg (B) comprising a second expansion device (22) controlled by the measurement of an intermediate temperature of the refrigerant leaving the first heat exchanger (5).