Thread: Inlet Air Temperature Circuit Fault

The wiring across the front of the head may have lost its insulation then shorted causing the fuse to blow. The MAF wont be working either if the fuse is blown.

Originally Posted by Graeme

The wiring across the front of the head may have lost its insulation then shorted causing the fuse to blow. The MAF wont be working either if the fuse is blown.

Do I need to replace the wiring? Can you tell me which fuse? Thanks

I would re-insulate any bare wire, perhaps by slitting oversized dual wall heat shrink, then enclose the harness in ribbed split tube. I'll dig out my D2 RAVE disc for the fuse number.

Fuse 2 will be the one.

If you don't already have a RAVE disc then you should buy one from the AULRO shop - they're cheap and invaluable.

Edit: The sensor is the one in the lid of the airbox.

The sensor on the airbox is AAP(ambient air pressure and temp) sensor and it has temp reading only on EU3 modells... the "Inlet air temp circuit" fault is related to MAP/IAT(inlet air temp) sensor on the inlet manifold, fuse F2 has nothing to do with that... it's not uncommon for the IAT side of the generically called MAP sensor to fail... put nanocom on "instrument" or "inputs fueling" mode and see the live reading of the air inlet temp, probably you'll get a constant reading of 25*C ... anyway for this fault the easyest is to replace the MAP/IAT sensor cos it's the first suspect...then if nothing changes you can start chasing a wiring issue which is hard... that's what i'd do, in the unlikely case of a wiring issue(which IMO would affect the MAP reding too) at least you'll have a spare MAP

it's described in RAVE - Engine management - Description - MAP/IAT and the other at AAP

AH yes, airbox is AAT - ambient. Too long since owning a D2.

Originally Posted by sierrafery

The sensor on the airbox is AAP(ambient air pressure and temp) sensor and it has temp reading only on EU3 modells... the "Inlet air temp circuit" fault is related to MAP/IAT(inlet air temp) sensor on the inlet manifold, fuse F2 has nothing to do with that... it's not uncommon for the IAT side of the generically called MAP sensor to fail... put nanocom on "instrument" or "inputs fueling" mode and see the live reading of the air inlet temp, probably you'll get a constant reading of 25*C ... anyway for this fault the easyest is to replace the MAP/IAT sensor cos it's the first suspect...then if nothing changes you can start chasing a wiring issue which is hard... that's what i'd do, in the unlikely case of a wiring issue(which IMO would affect the MAP reding too) at least you'll have a spare MAP it's described in RAVE - Engine management - Description - MAP/IAT and the other at AAP

Is the part number for IAT is MHK100640? On the website it is called Inlet Manifold Temperature sensor. Need to make sure I get the right one and I will get the live reading for Inlet Air Temperature today. What would be the right reading if the sensor is still good?

that's the part number, as i said it's MAP/IAT(two in one), it's most common name between enthusiasts is simply MAP but on sites is called other ways too, e.g. MAP Sensor TD5 (Bosch) MHK100640 Island 4x4 - Specialists in Land Rover and Range Rover Parts and accessories for all models. UK and worldwide mail order.

there's no standard chart for the readings cos they depend on some factors like EGR on/off size of intercooler, how hard the engine works, etc, normally on cold start the IAT is very close to the ambient temp and as the engine warms up it grows normally to ambient temp + 20 ... 30*C, with heavy load maybe even more...the gist for you is to not get a constant reading, probably 25*C or 0 or some other completely different than the range i explained