Test Driving

Fig 1: Identifying Engine Coolant Heater

Courtesy of VOLVO CARS OF NORTH AMERICA.

NOTE: The additional heater will not start if the engine coolant temperature (ECT) is in excess of approximately 75°C.

Checking the quantity of fuel

Engine on: The heater always starts and the quantity of fuel in the tank is checked for 1 minute. If the quantity of fuel is greater than 4 liters the heater continues to run, otherwise it shuts down.

Engine off: The quantity of fuel is checked before starting.

Warning text in the driver information module

Warning text is displayed in the driver information module if:

the quantity of fuel is too low.

-the battery voltage is too low.

Conditions for starting:

outside temperature < +3°C
the engine is running
quantity of fuel > 4 liters
no diagnostic trouble codes (DTCs) stored that would prevent starting
airbag not deployed.

Activate the heater.

When the heater is activated, allow it to run for a few minutes and check that:

the heater starts and runs normally
the heater does not smoke abnormally
there is no mechanical noise from the fuel pump (FP), water pump or combustion fan
there is no leakage from either the fuel lines and terminals or the coolant hoses and terminals
the coolant hoses from the heater are warm.

Stop the heater.

In warm weather (above 20°C) the heater may run unevenly. This is due to the fuel vaporizing. The heater is not normally intended to operate in such high temperatures.

If the car is not equipped with the trip computer function the heater starts in VIDA Car communication Section 36 Engine coolant heater.