Air conditioning circuit for a motor vehicle, through which there circulates a refrigerant and which comprises, in the direction in which the refrigerant circulates: ∘ a compressor, ∘ a first heat exchanger intended to have passing through it a flow of air external to the motor vehicle and positioned downstream of the compressor, ∘ an ejector positioned downstream of the first heat exchanger and comprising: • a first refrigerant inlet, connected to said first heat exchanger, • a second refrigerant inlet, and • a refrigerant outlet, ∘ a refrigerant phase-separation device comprising: • a refrigerant inlet connected to the refrigerant outlet of the ejector, • a first refrigerant outlet for refrigerant in the gaseous phase, which is connected to the compressor, and • a second refrigerant outlet for refrigerant in the liquid phase, ∘ an expansion device positioned downstream of the second refrigerant outlet of the phase-separation device, ∘ a second heat exchanger intended to have passing through it a flow of internal air intended for the motor vehicle interior, said second exchanger being positioned downstream of the expansion device, between said expansion device and the second refrigerant inlet of the ejector, characterized in that the air conditioning circuit further comprises a bypass line bypassing the phase-separation device and connecting: ∘ a first junction point positioned downstream of the refrigerant outlet of the ejector, between said ejector and the phase-separation device, and ∘ a second junction point positioned downstream of the first outlet of the phase-separation device, between said phase-separation device and the compressor, said bypass line comprising a third heat exchanger. ∘ a compressor, ∘ a first heat exchanger intended to have passing through it a flow of air external to the motor vehicle and positioned downstream of the compressor, ∘ an ejector positioned downstream of the first heat exchanger and comprising: • a first refrigerant inlet, connected to said first heat exchanger, • a second refrigerant inlet, and • a refrigerant outlet, • a first refrigerant inlet, connected to said first heat exchanger, • a second refrigerant inlet, and • a refrigerant outlet, ∘ a refrigerant phase-separation device comprising: • a refrigerant inlet connected to the refrigerant outlet of the ejector, • a first refrigerant outlet for refrigerant in the gaseous phase, which is connected to the compressor, and • a second refrigerant outlet for refrigerant in the liquid phase, • a refrigerant inlet connected to the refrigerant outlet of the ejector, • a first refrigerant outlet for refrigerant in the gaseous phase, which is connected to the compressor, and • a second refrigerant outlet for refrigerant in the liquid phase, ∘ an expansion device positioned downstream of the second refrigerant outlet of the phase-separation device, ∘ a second heat exchanger intended to have passing through it a flow of internal air intended for the motor vehicle interior, said second exchanger being positioned downstream of the expansion device, between said expansion device and the second refrigerant inlet of the ejector, ∘ a first junction point positioned downstream of the refrigerant outlet of the ejector, between said ejector and the phase-separation device, and ∘ a second junction point positioned downstream of the first outlet of the phase-separation device, between said phase-separation device and the compressor, said bypass line comprising a third heat exchanger.