ENGINE CODE

Here is the volvo fault code and description.

Diagnostic trouble code (DTC) information ECM-436B

Condition

The engine control module (ECM) checks power consumption on the leak diagnostic unit pump.
A diagnostic trouble code is stored if the current consumption of the pump in the leak diagnostic unit varies too much during the reference phase.
The diagnostic trouble code (DTC) can be diagnosed when the leak diagnostic system is run.
For further information about leak diagnostics, see VIDA Design and Function.

Substitute value
The leak diagnostic is disabled.

Possible source

Contact resistance in the terminals
Blocked hose between the filter and the leak diagnostic unit
Damaged leak diagnostic unit.
Fault symptom[s]

Malfunction indicator lamp (MIL) lit.

Start with having the engine control module software updated. That should be covered by a 10 year/150k mile extended warranty but you should call Volvo to verify that. You can also get a free software update from Volvo if you have a major service done. That software would update the engine, transmission, climate control, central electronic module and the drivers information module as a complete package. If the software does not take care of the fault you will need to replace the leak detection pump. Again call Volvo to see if they are participating in the program. If they are you should get a free diagnostic. What you would get at minimum will be a free scan of the fault and lets say it does need an updated software and it is covered by the extended warranty, they will update it and run a free leak detection pump test. Depending on the outcome of the test if it passes you are good. If it fails then they will need to charge you for further diagnosis or just may recommend replacing the leak detection pump. Good luck to you and keep us posted please.