| Heat output of air conditioner |
| l
| If the coolant circuit is not completely bled after filling, air may accumulate in the heating system heat exchanger and thus reduce the heat output. In addition, noise may occur or complaints may be received about differences in the temperature of the air from the vents. |
| Remedy in the event of poor heat output or noise from the coolant circuit |
| –
| Perform a test drive at fairly high engine speed (at least 10 minutes, engine speed above 2500 rpm). Select a low gear when doing so to prevent an excessively high vehicle speed. |
| –
| In the event of complaints about poor heat output at certain engine speeds, check incorporation of the heating system heat exchanger into the engine coolant circuit → Rep. gr.19. |
Note | t
| On vehicles with start/stop function and a manually controlled air conditioner, the stop function may be inhibited depending on the setting on the operating unit, air conditioning system control unit -J301- (e.g. in heating mode). The engine is started as soon as heating is requested. In cooling mode, there is no restriction of the stop function by way of the air conditioning system control unit -J301-. For checking,
„Read measured values“ in air conditioner
„Guided fault-finding“ function → Vehicle diagnostic tester. |
| t
| On vehicles with start/stop function and an automatically controlled air conditioner, the stop function may be inhibited depending on the setting on the operating unit, Climatronic control unit -J255-. If
„Defrost“ mode has been set for example, no stop function is possible or the stop function is terminated and the engine started as soon as this mode is selected. This also applies if the difference between the set specified temperature and the measured actual temperature exceeds a certain value in heating and cooling mode. For checking,
„read measured values“ in the
„Guided fault-finding“ function, air conditioner → Vehicle diagnostic tester. |
|
|
|
