Volkswagen Workshop Service and Repair Manuals

The Climatronic control unit is supplied with information from electrical and electronic components (information transmitters). The input signals from the information transmitters are processed in the control unit in accordance with specifications and the output signals then control the electrical components (final controls).

The Climatronic control unit -J255- is located behind the control and display panel -E87-.
To enable fault to be rapidly detected if a component fails or there is an open circuit, the control unit is equipped with a fault memory which can be interrogated using the fault reader V.A.G 1551.

Should a fault be detected in one of the sensors or components monitored, it is stored in the fault memory.

If a fault has been stored, the Climatronic will be switched off either partially or entirely depending on the severity of the fault.

If a fault which has a permanent adverse effect on the operation of the Climatronic is stored to memory, the display of the control and display panel -E87- flashes for approx. 15 seconds when the ignition is switched on. In the case of faults that do not cause the display to flash, the Climatronic control unit can allow the Climatronic to continue operating in emergency mode at the adjusted settings.

To commence fault finding, initiate self-diagnosis and retrieve the stored information with the fault reader V.A.G 1551.

The fault information displayed is used to refer to a fault table with notes on the possible causes for directed repair measures.