Last couple of morning the fbh has seemed to run but hasn’t really produced any heat into the cabin, noticed this morning that even though I could hear the fan in the wheel arch there was no ticking noise from the rear. I did top up the engine coolant about half a pint just before this happened and read somewhere this can cause water to get into the pump, not sure if that is so though. Going to put the IID on when I get home and see if that throws up any faults.

Temperatures are only just dipping below 16 degrees. The FBH also uses the ambient sensor and not the outdoor temperature sensor.

Once it's at or around 16 degrees, the system will only vent and not burn diesel to provide heat.

Test it at night when the outside and ambient temperature are very obviously significantly below 16 degrees. Also try manual Heat from the infotainment system instead of the remote.


If that doesn't work, perform the FBH fuel pump prime procedure in the IID.

If that doesn't work, replace the pump if you don't hear it clicking. 2015 Range Rover Autobiography 4.4 SDV8

Be aware, water pump may get stuck sometime and no pumping (or pumping weak), and no error code at the same time due electric circuit is ok. FBH will start and shut down in couple minutes in this case.
No clicking dosnt mean 100% fuel pump is death. No clicking = FBH not starting for some reason. It may be fuel pump, water pump, ignition, temp. sensor, fan, control module or what ever fault. Then FBH even dont try to start, thatwhy no clicking noise.
Also its possible there is no starting permit from HVAC: due low battery, ambient temp. too high, some other own fault...its quite complicated system.
Also FBH can go to lock mode due several failed starts.

They won’t produce heat until the outside temp falls to 5c and below 2009 (2010 MY) 5.0 Supercharged Autobiography
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Thanks for the replies chaps and the info, it has been acting up recently to be honest. Sometimes it will work and sometimes not like this morning, I’m the past when it hasn’t worked the dash light has been flashing and you can hear the ticking from the pump bit still no heat. The outside temperature here up North was 7degrees so it probably should have kicked in, I checked with the IDD this evening and it came up with a short circuit fault but I forgot to take the details, I’ve set it on the dash timed climate for in the morning and see what happens.

FBH worked perfectly this morning so the pump isn’t knackered