...that could help me by plugging it into my Thor 4.0 P38 that I rescued earlier this year please?
A friend has a Nanocom but it's gone faulty.
I've got it through a MoT and running quite well but would like to put it on a Nanocom to look at, amongst other things, what the issue is with the heater. I'm guessing blend motors but I understand they can be manipulated on the Nanocom to see if they are working before i dive in
I'm on the opposite side of the country for you otherwise I'd be happy to put the Nano on to check for you. You can check the blend motors manually though. With the engine warm, put both sides on 20C and check that air out of both sides is the same temperature (there may be a slight difference but not by much), then change one side to Hi and confirm it changes on that side, change it to Lo and check again. Then put that side back to 20C and repeat the same test on the other side. If the temperature changes on both sides as you expect it to, then try changing where the air is going and confirm that when set to windscreen it blows on the windscreen and so on. A good final test it to poke the Prog button. That should turn on the front and rear screen heaters, put the fans on high speed, both sides on Hi (hot), engage the AC compressor and direct the airflow to the screen.
If either side doesn't change temperature when you tell it to, then there is a problem with that blend motor. When you first turn on the ignition, they are driven from one end of their travel to the other and the feedback from each motor is checked to confirm it is doing what it should do. There are two problems that affect them. Either the flaps that the blend motor move have seized so the motors stall, or the feedback pots inside them have worn out so the HEVAC doesn't see the movement. First though, identify what the problem is. Bear in mind that if the HEVAC detects a fault with one motor in the self test, it will not try to move that motor again. Sods law says that if a motor sticks at one end of the travel or the other it will invariably stick at full hot in summer and full cold in winter!
Admittedly with the Nanocom you can drive the motors from one end of the travel to the other and monitor the feedback but that still doesn't tell you if the motor is moving and there is no feedback or if it isn't moving. In both cases, you need to get a few panels off so you can see the motors and check if they are actually moving or not.
Thanks GilbertD. I'm pretty sure it's all working except the drivers side blend motor although the passenger side stopped sending out hot air on request when we did our first long trip (beginning of December when we had temps down to -8) it's now decided to work again.
As the car had been essentially abandoned for 3 years I thought if I can get the blend motor moving it might respond to some exercise without having to pull the whole dash apart.
I also wanted to see if there are any codes stored as i have an intermittent SRS light on the dash.
You can exercise them without pulling the dash out (in fact you can change them without pulling the whole dash out). Take off the centre console side panels and undo the 4 screws holding the HEVAC in. Tilt it out at the top and it will then come out. Unplug the black connector to the blend motors (on the left, towards the back). If you look at that one you will see 3 sets of wires the same colour. The Black and Brown wires go to the actual motors, Left blend motor on pins 11 and 12, right blend motor on pins 9 and 10 and distribution motor on pins 6 and 16. If you use a 9V battery and connect it to those pairs of pins, you can power the motor from one end of the travel to the other. Connected one way round moves it one way, the other way round moves it the other way. You'll be able to hear them whirring away as they move and doing it a few times may be all you need to wake up the lazy ones.
A Thor will bring on the SRS light if it detects a fault but it will go out once the fault is cleared unlike the earlier GEMS which needs it to be reset with diagnostics even after the fault is cleared. Favourite fault with the Thor is the connector under one of the seats which gets disturbed whenever the seat is moved. Unplug, squirt with contact cleaner and plug back in is all that is normally needed.
Gilbertd wrote:
You can exercise them without pulling the dash out (in fact you can change them without pulling the whole dash out). Take off the centre console side panels and undo the 4 screws holding the HEVAC in. Tilt it out at the top and it will then come out. Unplug the black connector to the blend motors (on the left, towards the back). If you look at that one you will see 3 sets of wires the same colour. The Black and Brown wires go to the actual motors, Left blend motor on pins 11 and 12, right blend motor on pins 9 and 10 and distribution motor on pins 6 and 16. If you use a 9V battery and connect it to those pairs of pins, you can power the motor from one end of the travel to the other. Connected one way round moves it one way, the other way round moves it the other way. You'll be able to hear them whirring away as they move and doing it a few times may be all you need to wake up the lazy ones.
A Thor will bring on the SRS light if it detects a fault but it will go out once the fault is cleared unlike the earlier GEMS which needs it to be reset with diagnostics even after the fault is cleared. Favourite fault with the Thor is the connector under one of the seats which gets disturbed whenever the seat is moved. Unplug, squirt with contact cleaner and plug back in is all that is normally needed.
Great info. Thank you. If this rain ever stops I'll give that a go.
I managed to find time today to remove the HeVAC display and had a go at connecting a 9V Battery between the black and brown wires from each motor as suggested but wasn't able to get any reaction.
i'm a bit bemused because before I tried the above I had sat in the car and operated the direction controls and on each press of a button I could hear the flaps operating, the same for the recirc button.
When the heat was working it appeared to be coming from the passenger side, however, when i operate the temp buttons it is the driver's side flaps I can hear moving but not the passenger side.
I removed the glovebox as I need to repair the restraint anyway but that doesn't appear to give me any access so i removed the knee panel from the driver's side and that doesn't seem to help either (ducting in the way. So, where do I go from here.
My HeVAC dipaly has the book symbol and "!" on it. Is there any way to reset that without Nanocom or similar?
Book symbol will go out if no faults are found. If the problem is the blend motors you can sometimes reset it by unplugging the blend motor plug, turning the ignition on for 10 seconds, then off again. Then plug back in and try ignition on again. It will go out but if the fault is still there will come back on after a few seconds when it tries to check them, or immediately if there is another fault detected. Odd that you can't hear them with the battery though.
If you take the instrument cluster out (4 screws, one at each corner), you can see the blend motors. Do NOT turn the ignition on with the cluster unplugged (that will give you an SRS fault) but it can be moved to one side so you can see the blend motors moving when you tell them to.
Thanks GilbertD.
The 9 volt battery wasn't chucking out 9 volts so I'll have another go today.
I watched a video on removing the dash last night and I think I'll be taking the shortcut of cutting the ducting to get it out if ultimately I need access.
Dash out is not a fun way of spending a couple of days, it isn't difficult just very laborious. With a right angle screwdriver it is possible to get the blend motors out without cutting the duct (although you will need to if you are doing the heater core O rings). Don't try to drive the motors from the HEVAC with them not connected as that will also bring up a fault as they will travel further than normal.
The 9 volt battery across the brown and black wires will not drive any of the motors. Does the grey wire need to be energised as well?
I'm at the stage now of throwing things at it.
Looks like I'll have to disconnect battery and remove the instrument panel and see if I can get the duct out.
I'm usually quite patient but this is putting me to the test
No need to disconnect the battery, just make sure you don't turn the ignition on while things are disconnected.
This, https://web.archive.org/web/20180509124955/http://www.rangerovers.net/repairdetails/blendmotor.html is how to get to them.
No other wires will need to be connected. If you look at the diagram below, you'll see that only the brown and black wires are connected to the motors, the other 3 are for the feedback pot.
On the diagram
B=Brown
N=Black
W=White
RB=Red/Black
S=Grey
GilbertD, thank you for your advice thus far. I've managed to get the offending blend motor out:
I can't see how to upload pics on here unless hosted elsewhere.
I've split the motor housing casing and tried applying 9v directly to the motor but there's no response so I guess the motor id FUBAR.
I did put the meter on the motor contacts and it is indeed being supplied with 5 volts.
You may be able to wake the motor up with a squirt of contact cleaner through the holes so it gets on the brushes, spin it a few times then hit it with 9V and run it both ways.
Yes, pics do have to be hosted elsewhere (such as imgur) and linked to. There's a sticky at the top of the forum with instructions how to do it.
Gilbertd wrote:
You may be able to wake the motor up with a squirt of contact cleaner through the holes so it gets on the brushes, spin it a few times then hit it with 9V and run it both ways.
Yes, pics do have to be hosted elsewhere (such as imgur) and linked to. There's a sticky at the top of the forum with instructions how to do it.
i'll give it a go tomorrow.
Thank you
I couldn't wake the motor so ordered a s/h replacement from a breaker and wired it up.
Still no response from the motor so i put the meter on it.
When the other motors are turned on by operating the controls, I am seeing around 5v fed to the brown wire on each of them but not on the one that isn't working.
I had a spare HeVAc head unit (display doesn't work) so swapped it over and the situation remains the same so i can only surmise that the BECM isn't sending the command to move the motor.
Unplugging the HeVAC control units doesn't clear the book and "!" from the display so it could be that it needs clearing via Nanocom or similar.
Wish i had access to one - might have saved me a lot of work
Any thoughts?
There is one on Ebay now for a diesel p38. Nanocom
sorry - just read you have got the 4.0L.
BeCM only supplies the HEVAC with power and tells it if the engine is running, the power to the blend motors comes from the HEVAC unit itself. So no power to the motor would be a HEVAC fault but as you have swapped the HEVAC, it is unlikely you have two dead ones with the exact same fault. Unless you have tried putting power on the Black and Brown wires with the blend motors still connected to the HEVAC rather than with it unplugged. If you do that it burns out the output chip that sends power to the motor. I know, I've done it and had to replace 3 of the L272M chips that drive them.....
dave3d wrote:
There is one on Ebay now for a diesel p38. Nanocom
sorry - just read you have got the 4.0L.
£50 or thereabouts to add the GEMS or Thor licence and, as we are in the UK and BBS are in Cyprus, there is no VAT charged as it would be charged when whatever you buy arrives in the UK. But there isn't anything sent to you, it is an unlock code that you get from the website so no VAT.
To be frank I am a little wary of Nanocom as the friend who talked me into taking on this P38 has one. It's away back to Cyrus for a second time to be repaired as the display has failed a second time.
He only sent it a week or so ago and last time it was over a month before it came back..
I don't think I've tried putting power to the motor while it was connected to the HEVAC unit. Certainly not to both HEVAC units.
If I can connect a Nanocom, will it tell me if the output from the HEVAC is working?
It can't tell if there is an output, but it can tell you what the feedback pot is showing. So if the motor doesn't move, the feedback won't change but the same would happen if the feedback pot has gone open circuit. Admittedly, when they go they usually fail in such a way that there is an output but it isn't stable.
The alternative to the Nanocom, and cheaper, is EASUnlock V4 (updated from V3) from RSW Solutions (https://www.rswsolutions.com/index.php/range-rover-p38a/range-rover-p38a-eas-unlock-v3) that runs on a laptop. The only thing it can't do is connect to the SRS system but will do all the other ones. I've not had any problems with my Nanocom though, maybe your friend just got a Friday afternoon one?