I have a problem with my heater as it rarely seems to blow hot air into the cabin. If I press the PROG button I do get hot air.
Here are the readings on my Nanocom Do these values look OK? The aspirator temperature seems high.
I have seen that one of my P38's. In my case the fan was working fine, so I suspect it was warm air escaping the heater box & getting onto the aspirator thermistor. Another idea I had was maybe the fan motor getting a little warm ??
As I had the heater out a month ago to sort the split matrix & distribution flaps, I re-sealed the heater box properly. Car now nice & warm !!
BTW, "Prog" mode simply moves the hot-cold flaps to full hot position, so the aspirator is ignored in that mode.
If the aspirator thinks the inside of the car is 25 degrees and you have got the HEVAC set to a lower temperature than that, it will try to cool the car down to get it to the target temperature. A simple test is to give the aspirator (located behind the little grille below the clock) a squirt with brake cleaner which will cool it down rapidly (Nanocom should show that too), so the heater should ramp up the temperature from the vents very quickly.
Gilbertd wrote:
If the aspirator thinks the inside of the car is 25 degrees and you have got the HEVAC set to a lower temperature than that, it will try to cool the car down to get it to the target temperature. A simple test is to give the aspirator (located behind the little grille below the clock) a squirt with brake cleaner which will cool it down rapidly (Nanocom should show that too), so the heater should ramp up the temperature from the vents very quickly.
I just did the test with a squirt of brake cleaner that cooled down to 7.5C as it was evaporating. The heater then started to blow hot air.
I'm not sure what my next step is. The aspirator temperature is read as 25C before I even turn on the engine. I don't know how I can get it to read the ambient temperature.
Is the fan behind the aspirator clean and spinning freely? is there any clogged dust in the aspirator that could be causing it to read high for some reason?
Also, is the reading with the vehicle running? or before you start it? I know on the later P38's the external air temp sensor is delayed in reading until there is some road speed and a certain time (I think maybe 30 seconds) has gone past. I have never actually looked at it with the other sensors, but maybe all of them don't update straight away... (which doesn't make a lot of sense - but thinking from a coding point of view, if the temperature read is a sub-routine, then it would be easier to put a check in over the whole routine than maybe just one sensor).
If it's reading 25, and you put the temp to 26, does it start warning the air up (you should be able to see blend motor positions aswell in the nanocom to see when they are moving). Also, if you move the temp up to 'HI' then that will override the 'climate control' part of trying to reach a target temp, so you should get full hot at that point - which at least will blow it where you have the vents already set, rather than at the windscreen as in the 'PROG' mode
Marty
Sounds like, if you can live with it until then, an aspirator clean is on the cards when you come to collect your DSP amp......
Martyuk wrote:
Is the fan behind the aspirator clean and spinning freely? is there any clogged dust in the aspirator that could be causing it to read high for some reason?
Also, is the reading with the vehicle running? or before you start it? I know on the later P38's the external air temp sensor is delayed in reading until there is some road speed and a certain time (I think maybe 30 seconds) has gone past. I have never actually looked at it with the other sensors, but maybe all of them don't update straight away... (which doesn't make a lot of sense - but thinking from a coding point of view, if the temperature read is a sub-routine, then it would be easier to put a check in over the whole routine than maybe just one sensor).
If it's reading 25, and you put the temp to 26, does it start warning the air up (you should be able to see blend motor positions aswell in the nanocom to see when they are moving). Also, if you move the temp up to 'HI' then that will override the 'climate control' part of trying to reach a target temp, so you should get full hot at that point - which at least will blow it where you have the vents already set, rather than at the windscreen as in the 'PROG' mode
Marty
It's going to make it more difficult to diagnose if the reading isn't correct until the car is rolling along. The basic issue is that years ago I can remember the heater kicking out a lot more heat than it does now. It does work when I set the temp to 'HI' but still not as hot as I remember. It would be interesting to know whether it's normal for a stationary P38 to have the aspirator temperature read 25C.
I don't know if the interior aspirator sensor is part of the 'doesn't update straight away' ones, or if it does update straight away.
I'm meeting Nick at the workshop today to sort some more parts out for him - so I'll borrow his Nanocom (as I forgot to bring mine with me) and have a look on my RR as it's also a 2001 with the later HEVAC controller.
Not getting as hot as it used to could be a lot of things - from sticking blend flaps that don't fully go to hot, or restricted flow through the heater core.
Is your RR just on Petrol or LPG aswell?
Martyuk wrote:
I don't know if the interior aspirator sensor is part of the 'doesn't update straight away' ones, or if it does update straight away.
I'm meeting Nick at the workshop today to sort some more parts out for him - so I'll borrow his Nanocom (as I forgot to bring mine with me) and have a look on my RR as it's also a 2001 with the later HEVAC controller.
Not getting as hot as it used to could be a lot of things - from sticking blend flaps that don't fully go to hot, or restricted flow through the heater core.
Is your RR just on Petrol or LPG aswell?
No LPG just petrol (although running on E85 85% bioethanol when in France).
Moving & calibrating the various blend motors with my Nanocom seems OK so I don't think that the blend flaps are sticking.
The heater core was replaced less than two years ago so I don't think that it's clogged up. The heater core is about 85C while coolant temp is 90-95C.
blast of compressed air for the current one, and order a replacement aspirator from ebay :)
Yeah, I would try swapping the aspirator then.
I looked at mine on nanocom today and it was reading about the same as heater core (11-12 Deg) with the engine being off for awhile and just ignition on.
If I put my finger on the sensor it would go up in temp as expected, and drop again when finger removed.
With engine on and the system in auto, I could set the desired temp on HEVAC and then again with finger on aspirator, I could see the blend motors moving a bit, so I don't think there's a delay on aspirator sensor read.
Trying another sensor is probably a good place to start on your RR.
Martyuk wrote:
Yeah, I would try swapping the aspirator then.
I looked at mine on nanocom today and it was reading about the same as heater core (11-12 Deg) with the engine being off for awhile and just ignition on.
If I put my finger on the sensor it would go up in temp as expected, and drop again when finger removed.
With engine on and the system in auto, I could set the desired temp on HEVAC and then again with finger on aspirator, I could see the blend motors moving a bit, so I don't think there's a delay on aspirator sensor read.
Trying another sensor is probably a good place to start on your RR.
Thanks for the troubleshooting. It does look like the sensor is at fault.
romanrob wrote:
blast of compressed air for the current one, and order a replacement aspirator from ebay :)
Amazingly you can still buy a genuine STC3365 from JLR for £45.43. They either stockpiled too many or they don't fail very often.😀
https://parts.jaguarlandroverclassic.com/stc3365-sensor-temperature.html
That's the external temperature sensor, not the aspirator. Aspirator is JTF000030 which is available but a little more expensive https://parts.jaguarlandroverclassic.com/jtf000030-sensor-in-car-temperature.html?code=60907
I have a feeling I have a spare one, I'll have a look later and see if I can find it.
Gilbertd wrote:
That's the external temperature sensor, not the aspirator. Aspirator is JTF000030 which is available but a little more expensive https://parts.jaguarlandroverclassic.com/jtf000030-sensor-in-car-temperature.html?code=60907
I have a feeling I have a spare one, I'll have a look later and see if I can find it.
Wow! £167! I hope that cleaning all the fluff out of mine is all that is required.
Interestingly while you can buy new from JLR there aren't any listed on eBay in the UK. There is one from Latvia for £50 including postage that looks nice & clean & one from Spain that is £85 including shipping where they haven't even bothered to clean all the dust off.
Sorry, just checked. I've got a headlight switch, a few other dash switches, a couple of blend motors but no sign of an aspirator so hopefully cleaning the fluff out will get it reading correctly.
Apart from just putting the nozzle of a vacuum cleaner over the aperture below the clock how else can I clean it? I can't find how to remove it.
I've not (yet) had a rangerover with this issue. I did have a passat with this problem, a narrow vacuum cleaner end was all it needed to revive that.
My favorite non-greasy spray can cleaner is "brake and clutch" cleaner. But, since trichloroethane fell foul of regs - I can only find alcohol/butane mix. Could be problematic spraying this stuff into an enclosed space (especially with abundant sources of ignition). Nov 5th could come early.
Would only expect a solvent to be necessary if there is tar/nicotine build up. Hopefully compressed air (dry) ŵill do the job if the vac cleaner fails.
nigelbb wrote:
Apart from just putting the nozzle of a vacuum cleaner over the aperture below the clock how else can I clean it? I can't find how to remove it.
Centre console side panels off, knee panel off, switch panel off and it is screwed to the inside of the switch panel with two tiny but long pozi 1 screws. Once it is out, the best way of cleaning it is with a soft paintbrush as the fins of the fan get covered in dust as well as the thermistor.
Gilbertd wrote:
nigelbb wrote:
Apart from just putting the nozzle of a vacuum cleaner over the aperture below the clock how else can I clean it? I can't find how to remove it.
Centre console side panels off, knee panel off, switch panel off and it is screwed to the inside of the switch panel with two tiny but long pozi 1 screws. Once it is out, the best way of cleaning it is with a soft paintbrush as the fins of the fan get covered in dust as well as the thermistor.
It will have to wait until after our South of France road trip is over as while I have all my tools in the boot I don't think that it would go down too well with my wife as we are on holiday & while it sounds like a five minute job (famous last words😀) it's non-urgent.