Function
Function
Description of function of the operating status of the heater
The heater can have a number of different statuses. Each status and what should occur in it is described below.
Functions
The vehicle configuration can be read off to check what functions the car is equipped with. The following affect the function of the heater:
- Parking and additional heater function or additional heater function only (diesel engines)
- Parking heater or not (gasoline engines)
- Residual heater or not
- Electrical engine block heater (time controlled via the driver information module) or not.
Fuel driven parking heater
The user sets the desired start time using one of the two timer functions in the display on the combined instrument panel (driver information module) (5/1). The time is programmed by twisting the ring on the control stalk and by pressing the "reset" button for the desired time (timer 1, timer 2 or direct start). Direct start can also be used to start the heater.
The central electronic module (4/56) receives data about when the driver wants to drive from the control stalk module (steering wheel module) (3/130) and the combined instrument panel (driver information module).
The central electronic module calculates when the heater needs to start so that it is warm enough in relation to the outside temperature. Information about the temperature comes from the outside temperature sensor which is connected to the driver's or passenger door module.
The central electronic module calculates when the heater needs to start:
- The heater calculates when start is required (15-50 minutes before the intended departure at medium low temperatures between -10 °C and +15 °C)
- The run time of the heater is a maximum of 60 minutes at temperatures less than -10 °C
- The running time of the heater is at least 15 minutes before the planned departure (Warm temperatures between +15 °C and +25 °C ).
When the heater is started directly using the control stalk it runs until it is shut off or for a maximum of 60 minutes. The heater is on for 10 minutes after the set time to allow for the driver getting to the car late.
A text message is displayed in the driver information module when the heater is running.
Electrical heater with timer function
The desired departure time is set using the control lever module (steering wheel module) (3/130).
The central electronic module (4/56) calculates when the heater should start. The heater starts 2 hours and 45 minutes before the set departure time, irrespective of the temperature. A text message is displayed in the driver information module (5/1) when the electrical heater is running.
The accessory electronic module (4/78) electrically controls when the heater should be switched on and off. The engine block heater must be connected to a wall socket. The accessory electronic module activates a relay which closes the switch for a heater element.
Residual heater
This function can be ordered as an accessory. See the vehicle configuration to check if the car has a residual heater.
The function is activated in the driver information module (5/1) using the control stalk (compare to the parking heater). Information about activation is sent to the central electronic module (4/56) and climate control module (3/112). The blower fan and damper settings are set by the climate control module. The central electronic module transmits data to the combustion preheater module (4/7) instructing it to activate the water pump.
When the residual heater is activated it will operate as long as the coolant temperature is above 30 °C or for a maximum of 20 minutes or until the function is switched off.
This function is used when the coolant is already warm. The coolant pump is started thereby circulating the coolant. The heat is distributed from the coolant to the passenger compartment unit in the climate control unit and on to the passenger compartment.
When the residual heater is running, the passenger compartment is heated by the climate control module controlling the fan and damper according to a customer parameter (Applies only to electronic climate control (ECC)). This parameter is used to set the distribution between the defroster and the floor. The normal setting is 30% defroster and 70% floor.
Additional heater
The additional heater is standard in cars with diesel engines (certain markets). This function is used for cars in cold markets to provide extra heat to the climate control module. The heater functions in the same way as the parking heater although the start conditions are different. These are controlled by the central electronic module. There is no physical difference between the parking heater and the additional heater. The difference between functions is the software.
Additional heater and parking heater
If a diesel engined car has a parking heater, the car will have both the additional heater and the parking heater functions.
If the parking heater has been programmed and the driver comes to the car earlier than anticipated, the additional heater will not engage until the car is started. The additional heater then determines if the heater should be on or off, even if the driver attempts to disengages the heater using the control stalk.
Remote start
Cars with an accessory electronic module can have a remote start function for the heater. This allows the heater to be started using a pager. A stop or start signal is transmitted from the accessory electronic module (4/78) to the central electronic module which starts the heater (4/7). This function is available for both fuel driven and electrical heaters.