Thermo Plunger Relay error

[ska_abbas]

Hi all, 

I have Nissan Qashqai 2015 Ntec+ Diesel and the other day the engine management light went on. 

I took it to the garage and he used the computer for diagnosis and it turn out 'Thermo Plunger Relay' error. The garage guy wasn't sure about what it is, and said it could be the DPF....

Has anyone encountered anything with Thermo Plunger, what its job is, and how much does it cost to replace it? 

Any advice would be highly appreciated 

Thanks 

[Trevor]

Not sure the diagnosis is anything more than if it is the DPF then it is best to give the car a good blast to clear it through and at zero cost

 

[ska_abbas]

The guy advised me not to go on motorway in case the issues escalates and DPF would become problematic, which is a major cost. 
However, I read on internet that if you drive at 60-70 miles for 30-40 minutes, the DPF usually clears itself 

[Trevor]

You are correct with the latter, always worked on every car I have had a DPF issue with