Design

Design

Heater





The heater has the following internal electrical components:
- control module
- combustion air fan motor
- glow plug
- coolant temperature sensor
- overheating sensor
- fuel preheater (diesel only)

External electrical components:
- Coolant pump
- fuel pump
- remote start device (accessory)
There are 6 connectors above the control module. 3 of these are accessible from outside and are for connection to the vehicle, coolant pump and fuel pump. The other 3 are under a plastic cover and are for internal electrical components. The fan motor is directly connected to the control module circuit board with 2 pins.

Combustion preheater module (CPM)




The control module is integrated in the heater - located under a cover at one end of the heater. The connection for the combustion air fan is located on the underside of the control module.
The control module receives signals from the sensor and other components. The control module uses this data to regulate heater start, output, shut-off, etc.
The control module also continually monitors heater components to ensure proper function.

Coolant pump




The coolant pump is located under the engine control module (ECM) in the cold space at the back edge of the engine compartment toward the passenger compartment.
The coolant pump is driven by an integrated electric motor. It is used to circulate coolant in the engine cooling system.
There are diagnostics for the electronics of the coolant pump.

Fuel pump




The fuel pump is an electric piston pump that doses the right amount of fuel to the heater. The fuel pump power supply is connected to the control module and grounded to the grounding point. By pulsing the feed with a varying frequency, the control module can determine the amount of fuel delivered for combustion.
The fuel pump is located at the fuel tank, connected without filter to a separately prepared tank connection.
There are diagnostics for the electronics of the fuel pump.

Coolant temperature sensor




The coolant temperature sensor enables the control module to determine coolant temperature and thereby when the heater should be switched on or off.
The coolant temperature sensor is integrated in the heater, located next to the overheating sensor under a cover on one side of the heater.
There are diagnostics for the electronics of the coolant temperature sensor.

Overheating sensor




The overheating sensor helps the control module determine coolant temperature and thereby determine heater temperature and protect the heater from overheating.
The overheating sensor is integrated in the heater, located next to the coolant temperature sensor under a cover on one side of the heater.
There are diagnostics for the electronics of the overheating sensor.

Glow plug




The glow plug is positioned so that part of it is in the combustion chamber. It has a wire that starts to glow when it receives current from the control module. The glow plug is activated by the control module and then ignites the fuel/air mixture in the combustion chamber.
The control module also uses the glow plug to register whether there is a flame in the combustion chamber. The signal from the glow plug is used to switch off the heater, etc.
There are diagnostics for the electronics of the glow plug.

Combustion air fan




The combustion air fan sucks in air from the air intake and forces the air into the combustion chamber during combustion.
The combustion air fan is integrated in the heater, located below the control module.
There are diagnostics for the electronics of the combustion air fan.

Fuel preheater (diesel only)




The fuel preheater heats the fuel (diesel) so that it flows more easily in cold conditions.
The heater body of the fuel preheater is integrated in the heater, located next to the glow plug.
The heater body of the fuel preheater is regulated via a pulse width modulated signal (PWM).
There are diagnostics for the electronics of the fuel preheater.

Remote start equipment





Remote start equipment consists of:
- handheld transmitter
- control module
- receiver (antenna)
- cable harness
The control module is located within the sound insulation at the base of the passenger side A-pillar.
The receiver is located at the upper right corner of the windshield (left corner on right-hand drive vehicles). It is connected to the control module via a coaxial cable. The remote start unit is connected to the combustion preheater module (CPM) via the prepared cable harness. The remote start unit communicates with the combustion preheater module (CPM) via the supplier's own serial communication.
The handheld transmitter is driven by two 12 V batteries of type MN21/23. A maximum of three handheld transmitters can be programmed. See vehicle Owner's Manual for programming.
Remote start equipment can only be retrofitted.