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A/C relay

A/C relay




When the A/C compressor is activated from the ACC or MCC and all other condition have been fulfilled, DICE will send bus information "A/C ON". The value is used by Trionic T7.

The control module then calculates the impending torque requirement of the compressor on the basis of the A/C pressure and then requests a corresponding increase in the air mass/combustion. After a short delay the control module grounds pin 4, which is connected to the A/C relay.

The control module activates the relay only when the engine has been started.




Diagnosis


• Diagnostic trouble code P1656 will be generated in the event of a break or short-circuit to ground.

• Diagnostic trouble code P1657 will be generated in the event of a short-circuit to B+.

Note

The A/C request from DICE can be read with the diagnostic tool.