

WIRING DIAGRAM - ADDITIONAL HEATER - Alfa Romeo 159 1.9 JTD 16V Fino a 12/05
COMPONENTS - ADDITIONAL HEATER - Alfa Romeo 159 1.9 JTD 16V Fino a 12/05
Component code | Description | Reference to the operation |
A001 | BATTERY | |
B098 | SUPPLEMENTARY FUSE BOX | - |
C016 | AIR CONDITIONING UNIT EARTH | - |
D008 | AIR CONDITIONING-HEATER FRONT COUPLING | - |
J36 | ADDITIONAL HEATER RELAY - 1 | - |
J37 | ADDITIONAL HEATER RELAY -2 | - |
M070 | CLIMATE CONTROL SYSTEM CONTROL UNIT | |
O025 | ADDITIONAL HEATER RESISTANCE | - |
COMPONENT LOCATION - ADDITIONAL HEATER - Alfa Romeo 159 1.9 JTD 16V Fino a 12/05
Component code | Description | Reference to the operation |
A001 | BATTERY | |
B098 | SUPPLEMENTARY FUSE BOX | - |
C016 | AIR CONDITIONING UNIT EARTH | - |
D008 | AIR CONDITIONING-HEATER FRONT COUPLING | - |
J36 | ADDITIONAL HEATER RELAY - 1 | - |
J37 | ADDITIONAL HEATER RELAY -2 | - |
M070 | CLIMATE CONTROL SYSTEM CONTROL UNIT | |
O025 | ADDITIONAL HEATER RESISTANCE | - |
DESCRIPTION - ADDITIONAL HEATER - Alfa Romeo 159 1.9 JTD 16V Fino a 12/05
The vehicle climate control system is insufficient via the heater unit when the engine is cold, especially for diesel engines which take longer to warm up.On these versions there is also an additional heating system which is activated when the engine is first running, depending on the temperature of the engine coolant.The system consists of an additional heating device, located inside the heater unit: this device contains two resistances (PTC1 - 300 W and PTC2 - 600 W).The operation of the resistances is controlled by the climate control system control unit which operates either just one of them or both thereby providing gradual heating with a maximum power of 900 W according to a control unit that depends on:- the temperature of the engine coolant (about 60°C);- the engine speed (which should be above a 700 rpm);- the battery voltage (which should not go down below 12.2 V).For more detailsThe power supply for one, two or three resistances is operated by means of two relays located on the actual heater unit:- 1. Level: activated by the first relay (300W);- 2. Level: activated by the second relay (600W);- 3. Level: activated by both relays (900W)The power supply line is protected by two MIDI maxi fuses located in a special additional fuse box at the side of the battery.
FUNCTIONAL DESCRIPTION - ADDITIONAL HEATER - Alfa Romeo 159 1.9 JTD 16V Fino a 12/05
The relay J36 controls the engagement circuit for the first additional heater resistance; the power supply for the relay arrives from the line for fuse F74 of the additional fuse box B98.The relay J37 controls the engagement circuit for the pther additional heater resistance; the power supply for the relay arrives from the line for fuse F76 of the additional fuse box B98.The coil for relay J36 is energized by a signal for the engagement of the first resistance for O25A - from pin 7 of M70.The coil for relay J37 is energized by a signal for the engagement of the second resistance for O25B - from pin 9 of M70.