stjohnsmythe
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Need to replace the HEVAC unit in my P38. Can anyone advise which model/part number I need to go for (mine is a 98)?
Cheers!
Cheers!
P38 HEVAC unit versions
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Datatek
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Only 2 versions that I know of, one drives the aircon compressor direct, the later one drives it via a relay. If your car has a relay for the aircon compressor you need the later version.
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- Preston Lancs.
If you are buying a used unit get the same part number as the one you have fitted.
stjohnsmythe
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Unfortunately my model has a fault Range Rover P38 Maintenance repair improvements and tips learned by experience by ownership.
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- Preston Lancs.
Unfortunately there are a few incorrect assertions in that. The Hevac does not control the compressor. It supplies power to the dual pressure switch when aircon is selected. It is the dual pressure switch that controls the compressor. In later models the Hevac supplies power to pull relay 3 which then powers the dual pressure switch. So relieving it of the load applied to it in earlier versions. My vehicle is fitted with the latest version JFC102550 (heated seats) but has no relay 3 and works fine.
Grit Valve
2000 4.6 Vouge
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Hope your not buying new
Climate Control Head Atc - JFC102550G | Range Rover P38A | Range Rover | British Parts UK
Climate Control Head Atc - JFC102550G | Range Rover P38A | Range Rover | British Parts UK
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- Preston Lancs.
Hope your not buying new
Climate Control Head Atc - JFC102550G | Range Rover P38A | Range Rover | British Parts UK
Yes a little bit on the steep side. Wonder just where they get their prices from.
Grit Valve
2000 4.6 Vouge
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I always like to buy new but that is ridiculous .
Howard electrical Hevac specialist
Unit 5, Faygate Business Centre Faygate Lane, Faygate, Horsham, west sussex, RH12 4DN
Tel: 01293 852258
Op try these I spoke to them once said they could test and repair the unit
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stjohnsmythe
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My AC works, but this extract describes the fault:
'Now everything worked almost perfect, the only issue was that every time
I started my RR the HEVAC started with a snowflake symbol and displayed
0deg Celsius, I then had to drive for a few minutes and then turn of and
restart the engine to get correct readings, occasionally the problem went away
by itself after a few or more minutes of driving.
After investigations it showed up to be a service letter available for this particular
problem, this service letter stated that a programing error in the HEVAC chip is the
cause to wy the HEVAC control panel nead some time to get awake'
Grit Valve
2000 4.6 Vouge
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Are you sure the outside temp sensor is working correctly
stjohnsmythe
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Pretty certain. Once it registers the correct temperature it's consistent for the rest of whatever journey I'm on. Normally when started from cold i.e. left overnight the temperature is correct. If I then drive and turn the car off for more than ten minutes it registers 0 degrees on restart. After driving for 5-10 minutes it then slowly starts to creep up to the correct temp. AC doesn't work until it registers 1 degree or higher so a bit annoying having to wait when it's hot outside!
Grit Valve
2000 4.6 Vouge
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That would be Bulletin 0011. L85486bu. Issue 1, dated 28/07/99. And the recommended part replacement is JFC 102550 (with heated seats) JFC 102540 (without heated seats). Suggest you have a look at flebay, new as Grit points out are megabucks.
stjohnsmythe
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