014

Symptom: Parking heater fails to start.

014

Fault symptom

Parking heater fails to start.

Condition

Coolant temperature at least 70°C.

The difference between test readings obtained on coolant temperature sensor 1 and coolant temperature sensor 2 is greater than 15°C.

Parking heater activated.

Fuel pump running.

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 coolant level

•	Check that the coolant level in the cooling system is between min. and max.

Test results OK?

YES

-	Go to point 3.

NO

-	Go to point 2.

2. Check for leakage

•	Top up with coolant to the recommended level.

•	Check that there is no leakage.

Test results OK?

YES

-	Bleed the system.

-	Go to point 10.

NO

-	Rectify the leak.

-	Top up with coolant to the recommended level.

-	Bleed the system.

-	Go to point 10.

3. Check coolant hoses

•	Check that there are no kinks in the coolant hoses.

Test results OK?

YES

-	Go to point 4.

NO

-	Eliminate any kinks in the coolant hoses.

-	Go to point 10.

4. Check intake and exhaust hoses.

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

Test results OK?

YES

-	Go to point 5.

NO

-	Repair or replace the hose or hoses concerned.

-	Go to point 10.

5. Check water circulation

•	Contact SID.

•	Activate parking heater (ON).

•	Check that the water pump starts.

Test results OK?

YES

-	Go to point 7.

NO

-	Go to point 6.

6. Check the water pump

•	Unplug the water pump connector.

•	Connect test lamp 86 11 857 to the female connector pins.

•	Contact SID.

•	Activate parking heater (ON).

•	The lamp should come on.

Test results OK?

YES

-	Change the water pump.

-	Go to point 10.

NO

-	Check that there is no open circuit in the leads between the water pump and control module.

-	Go to point 10.

7. Check the non-return valve

•	Check operation of non-return valve.

Test results OK?

YES

-	Go to point 8.

NO

-	Change the non-return valve.

-	Go to point 10.

8. Check Coolant temperature sensor 1

•	Lower the heater to gain access to the control module.

•	Remove the parking heater control module.

•	Take a resistance reading across pins 11 and 12 in female connector B2.

•	The reading obtained should be the same as that in the diagram in Technical Data.

Test results OK?

YES

-	Go to point 9.

NO

-	Change engine coolant temperature sensors 1 and 2.

-	Go to point 10.

9. Check Coolant temperature sensor 2

•	Take a resistance reading across pins 9 and 10 in female connector B2.

•	The reading obtained should be the same as that in the diagram in Technical Data.

Test results OK?

YES

-	Go to point 10.

NO

-	Change engine coolant temperature sensors 1 and 2.

-	Go to point 10.

10. Final check

•	Clear the diagnostic trouble codes 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 ’Before changing a control module’.