Considering the fact that on Discovery the Land Rover button on the fob can be programmed to turn on the low beam and also it's generally not used so much, I've made a little logic in order to use these things for starting the FBH.
Normally, the low beam is ON only when the ignition is ON. Well, the only time it will be ON when the ignition is OFF is when you press that button on the remote.
With a small microcontroller, in which I've implemented a part of the W-Bus serial protocol, I solved the problem.
Now, when you need the FBH, turn ON the low beam with the remote control for 2-3 seconds and that microcontroller sees that the lights were ON and then turned OFF after a short period of time when the ignition was OFF and turns the heater ON for 15 minutes.
I've put a limit of 15 minutes for battery health and anyway it's enough to bring the coolant temperature to 70-80 degrees.
In fact the logic is this:
- if the lights are turned on between 1 to 5 seconds, the FBH starts.
- if the lights are turned on between 5 to 15 seconds, the FBH stops.
- normal button/low beam usage of 30 seconds or more doesn't affect the FBH.
Below the schematic diagram and the hex file to be programmed into the microcontroller, using any PIC programmer. The signals are self-explanatory.
You can find PIC programmers on the net, some being even home-made.
Also the source code is available for those that want to improve it, but, for many, the PIC's firmware could be enough in order to get things done.
As a different approach, the LOW BEAM signal can be driven by any remote control (radio, GSM, etc) that can pulse that input for 2-3 seconds.
But the Land Rover button approach can be enough for the one that have the car on the driveway and sees its lights. The range of the fob is quite enough.
A few later words...
It is known that if you're using a 1533 timer, when you wake up the car, the FBH will stop.
Because this implementation is using, in its dialog with the FBH, the same addressing mode as the Webasto Thermo Test program, the FBH will keep running even if you're waking up the car with the remote or any other means.
UPDATE, November 16, 2014 - Version 1.06 https://www.disco3.co.uk/gallery/albums/us...v106~0.rar
This version has both a time limit (15 minutes) and a temperature target (75 degrees Celsius)
If you want to modify them, you can adjust them inside the source code (MINS_TO_RUN, MAX_TEMP) and then the sources must be recompiled.
This way things are optimized, meaning whichever condition is reached first will stop the FBH.
Any combination of conditions can be made.
For time limit only, set a target temperature to an unrealistic temperature, for example 150 degrees.
For temperature limit only, set a time limit to an unrealistic time, for example 250 minutes.
Last edited by alex_pescaru on 4th Jan 2022 10:08 am. Edited 20 times in total
Member Since: 28 Apr 2011
Location: Perthshire
Posts: 743
So basically you can turn on the FBH using the landrover button on the Key?? That would be a great achievement Defender 90 CSW MY06
Discovery 3 SE MY05 (Gone but still on the forum )
Defender 90 CSW MY02 ( Gone)
Discovery 3 GS MY08 ( Gone)
Last edited by Bev on 15th Jan 2014 10:02 pm. Edited 1 time in total
15th Jan 2014 7:24 pm
maplecottage
Member Since: 01 Feb 2011
Location: Norfolk
Posts: 3171
Why are some people so clever
15th Jan 2014 8:16 pm
Robbie
Member Since: 05 Feb 2006
Location: ¯\_(ツ)_/¯
Posts: 17932
Alex, that is genius - well done!
Land Rover - Turning Drivers into Mechanics Since 1948
Member Since: 03 Sep 2006
Location: Manchester
Posts: 14372
Excellent
Might have to dust off my old pic programmer
You should consider making some of these for sale ... It's a no brainer only having to carry one key fob G4 Gone ...but not forgotten
15th Jan 2014 8:32 pm
nighthawk
Member Since: 24 Jul 2010
Location: Malta
Posts: 1163
Amazing as always Alex
Where do you obtain detailed technical description about the wbus protocol (as detailed as needs to be to implement it)?
Really wanted to do this (ie. implement part of the protocol) a while ago but ended up getting a 1533 timer as I couldn't find any documentation about the protocol.Dennis
2006 Discovery 3 TDV6 Commercial Manual Buckingham Blue
Last edited by nighthawk on 15th Jan 2014 8:51 pm. Edited 1 time in total
15th Jan 2014 8:42 pm
alex_pescaru
Member Since: 19 Dec 2010
Location: RO
Posts: 270
Thanks guys for the appreciations !
As for sale....
All it's a hobby and for me this means: concept, design, test, share, move on... So, no sale...
But if anyone wants to do it, or to improve it, just go for it. As I've said, I will share the sources if needed.
It works on my Freely2. A couple of my friends also built it for their cars and I know of a Disco3 owner that had built it (with a small modification, another line driver).
Mods:
Original Beanie Narpy Grill, Black lettering, De-Tango'ed, Side steps, Hids LEDs upgrade, Halo DRL, Smoked side repeaters, D4 Bluetooth upgrade, Flacks magic with the fault mate, Upgraded D4 compressor, ERG's blanked, Tints, D4 rear lights, Short rails & cross bars, LR Ladder. Reversing camera (needs activating!!)
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
clever
