Thanks to this forum I was able to prevent myself messing my pants when this error message appeared yesterday. I had been working on realigning my rear light and as a result the rear boot lights had been on for prolonged period. After I jumped into the car started fine but then was listening to the radio with engine off for about 15 mins. Turned ignition and got the dreaded HTC fault.I had the iid tool and was able to check battery level it was at 11 volts meaning suspect battery .left it over night on charge went out this morning and all well. Battery has been dodgy for a while its a bosch and only 2 years old so hopefully should be able to get a replacement through 5 yr warranty as its only 2 yrs old.  Present :2008 TDV8 HSE
Gone Audi A5 2.7TDI
Gone Discovery 3 HSE
Gone Mercedes CLK
Gone Range Rover 2.5 DSE

Managed to get a replacement battery under warranty just in time for winter too happy days Present :2008 TDV8 HSE
Gone Audi A5 2.7TDI
Gone Discovery 3 HSE
Gone Mercedes CLK
Gone Range Rover 2.5 DSE

i did the same as you Conner... my year old 020 started to suffer a bit , probably cos i didnt use the range enough and ECP changed it without any quibbles.. ... - .- -.




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