64 02 00 (553) IHKA Control Panel: Led In A/C Button Flashes

64 02 00 (553) IHKA Control Panel: LED In A/C Button Flashes

All models with integrated automatic heating and air conditioning (option 534)

Complaints:
After a new IHKA control panel has been installed, the LED in the A/C button flashes.

Cause:
The flashing of the LED in the A/C button indicates that the automatic air-conditioning system is in the compressor protection mode. This protective function is intended to ensure an adequate refrigerant distribution the first time the air conditioner is operated (in the vehicle factory), before the engine is revved up.

The spare part is identical to the IHKA control panel used in series production. For this reason, the said protection mode is always active the first time a new IHKA control panel is installed. The LED in the A/C button will then flash continually until the A/C compressor has been engaged for about 90 seconds at an engine speed of less than 1500 rpm.

Affected vehicles:
All models with integrated automatic heating and air conditioning (option 534)

Procedure:
After a new IHKA control panel has been installed, the air conditioner must be run continually with the engine at idling speed until the LED in the A/C button stops flashing.

Under certain marginal conditions (e.g. very low ambient temperatures), it is possible that the A/C compressor is not permanently active. In such cases, the LED in the A/C button can continue flashing for several minutes.