Year Model Changes

The heating and ventilation system is continuously being modified. The various parts have been developed and better methods introduced. In addition to the fact that the various components have been modified physically, the Automatic Climate Control (ACC) control module has also been improved.

New software has been developed which better controls the temperature in the cabin and more diagnostic trouble codes have been introduced. For this reason, it may be useful to go through the modifications which have taken place over the years and to look at both mechanical and electronic improvements which have been made.

M1986
- Compressor moved to the center of the car in order to make it easier to repair and a new groove added to the pulley.
- Extra radiator fan at the front in order to increase cooling capacity in certain markets.
- The pressure switch in the A/C system has been increased to a three stage switch which sends a signal to the extra fan at 15 bar (210 psi) and breaks current at 27 bar (380 psi) in order to control the A/C system better.
- A/C start delay of about 10 seconds so that the engine has time to achieve idling speed, chassis No. CG1001945 and after.

M1987
- The electrically driven fan in the interior air sensor is integrated in the sensor for more accurate readings.
- All side defroster air is concentrated in the loudspeaker grilles from chassis No. CH1007949 LHD and CH1024270 RHD.
- The light intensity in the ACC panel is automatic, depending on the light level in the cabin, in order to make it easier to read.

M1988
- Defroster fans in rear doors have been introduced to cars with ACC for improved defrosting of rear side windows.
- Longer floor ducts for increased comfort.
- 7 cylinder A/C compressor which can be retroinstalled.

M1990
- ACC generation 2 introduced with built-in fault diagnosis, ISAT scan tool communication and the possibility of user programming.
- New solar sensor which, in addition to intensity, also senses angle of incidence of solar radiation.

M1992
- Rear A/C unit introduced as an option for increased cooling.
- ACC unit has a "Rear" button for controlling rear A/C.
- R134a refrigerant introduced, in certain markets, in order to protect the ozone layer. Components in cooling system adapted for this.
- Due to the new refrigerant, the three stage pressure switch has new settings.

M1993
- All cars supplied with A/C have R134a refrigerant.
- Rear A/C discontinued, along with its control button on the ACC panel.

M1994
- Windows with lower heat transmission introduced in order to reduce the effect of solar radiation on interior temperature. Marked Sekurisol. The heat absorbed by the glass is transferred to the air when driving.
- New solar sensor introduced due to the new windows. Ordinary sensor still available for markets without the new glass.
- New software in ACC control module for improved control.
- Extra holes in heater housing for improved flow to floor.
- R134a refrigerant available for converting systems still operating with R12.

M1995
- New solar sensor without electronics (located in ACC instead).
- New software in ACC control module for improved control.