056

Symptom: Parking heater fails to start.

056

Fault symptom

Parking heater fails to start.

Condition

All permitted attempts to start have been utilized.

Parking heater activated.

Diagnostic help

Parking heater can be activated with Tech 2.

Parking heater function can be programmed in SID.

Eberspächer diagnostics instrument used for diagnosis.

Diagnostic procedure

1. Check flame temperature sensor

•	Check that neither diagnostic trouble code 064 nor 065 has been generated.

Test results OK?

YES

-	Go to point 2.

NO

-	Deal with the diagnostic trouble code concerned.

-	Go to point 6.

2. Check exhaust and intake hoses

•	Check that the exhaust and intake hoses are not clogged.

Test results OK?

YES

-	Go to point 3.

NO

-	Repair or replace the hose or hoses concerned.

-	Go to point 6.

3. Check fuel pump

•	Contact: SID.

•	Activate parking heater (ON).

•	Listen to hear whether the fuel pump starts after about 45 seconds.

Test results OK?

YES

-	Go to point 4.

NO

-	Check whether diagnostic trouble code 047 or 048 has been generated.

-	Deal with the diagnostic trouble code concerned.

-	Go to point 6.

4. Check fuel lines

•	Check that no leakage occurs in the fuel lines between heater and fuel pump.

Test results OK?

YES

-	Go to point 5.

NO

-	Rectify the leak.

-	Go to point 6.

5. Check fuel pump capacity

•	Check that the battery is sufficiently charged (11-13 V).

•	Lower the heater to gain access to its fuel line.

•	Detach the fuel line from the heater.

•	Place the end of the fuel line in a measuring flask.

•	Contact: SID.

•	Activate parking heater (ON).

•	If fuel flows out at a constant rate, about 40 seconds after activation, the fuel line is filled and bled.

•	Empty the measuring flask.

•	Activate parking heater (ON).

•	The fuel pump is activated for about 90 seconds.

•	Check the amount of fuel in the measuring flask.

•	Value should be 9.3-10.7 cm 3 /90 s.

Test results OK?

YES

-	Check that the fuel pipe in the heater is not clogged.

-	Go to point 6.

NO

-	Change the fuel pump.

-	Go to point 6.

6. Final check

•	Delete DTCs in all systems.

•	Contact: SID.

•	Activate parking heater (ON).

•	Perform a functionality check.

•	Evaluate the functionality check.

•	Check that the diagnostic trouble code has not recurred.

Test results OK?

YES

-	Fault rectified successfully.

NO

-	See ’Procedure for replacement of control module’.