Calibrating, ACC

Adjusting The Cabin Temperature Scale
Using ISAT scan tool command "INDOOR TEMP.SENSOR", it is possible to change the way the cabin temperature sensor interprets the cabin temperature. If the cabin temperature sensor's offset is increased, the temperature in the cabin will be increased by the corresponding number of degrees. Adjustment is in steps of 0.1 °C.

NOTE: This adjustment should only be made after careful consideration. Adjustment is possible up to ± 2.5 °C. If adjustment is too great, the ACC system may react completely differently when starting from cold. Significantly more cooling or heating and high fan speeds can be achieved. An appropriate adjustment range is ± 0.3 - 1.0 °C.





Changing The Influence Of The Solar Sensor
Using the adjusting command "SOLAR SENSOR" the influence of the solar sensor on the ACC control module control program can be changed. Value from factory =33.

NOTE: The ISAT scan tool is prepared with this command. This command should not be used before information about it has been distributed, e.g. in a Service Information.





Fan Delay When Starting
Using the adjusting command "FAN DELAY", the cabin fan's pre-programmed start delay can be cancelled.

Under certain conditions, the start of the cabin fan is delayed for 15 seconds when the car is started to prevent misting on the windscreen.

If the delay is cancelled, fan speed is controlled by the ACC control module.








Fan Current At Start
Using the adjusting command "FAN CURRENT START", it is possible to change the maximum fan current limit (proportional to fan speed) that the ACC system starts with during cold start.

From factory, maximum fan current when starting is limited to 5.5 A. Starting current can also be below 5.5 A or it can be programmed. Fan current is increased by the ACC control module as blended air temperature increases.
Maximum start current can be adjusted between 2.5 - 12.5 A according to the customer's requirements. Recommended fan current when starting is 4 - 7 A. This adjustment should be made after careful consideration, preferably in consultation with the customer.

Example of how adjustment can be carried out in consultation with the customer:
Connect the ISAT scan tool and read "FAN". Ask the customer to set the fan speed he/she requires at start.

The control voltage fed to the fan corresponds to a certain current strength. Using the ISAT scan tool, program the required fan speed according to the adjacent table. (Table shows approximate values).