Disco 2 Webasto Fuel Burning Heater install

Could be wrong but I thought I'd read somewhere that the WBUS was removed from the later D3 or D4 Webasto's.

Nodge68 said:

my FL1 fan used 1.5A to run on minimum speed, which is nothing really, and is definitely worthwhile.

Click to expand...

You can't compare the FL1 with the D3, on the D3 you have to power up the whole system to make the blower work cos you can't splice into the blower's circuit just like that as when you turn ignition off the system closes the air duct flaps automatically, those are acting like the folding mirrors(i presume to stop bugs or something) hence my first reply which you cotradicted, when the system is powered up it takes around 5A without blower... i've tried myself to do it on D3 to help a friend and when i realised how much hassle it would involve i gave up.

backinblack said:

Could be wrong but I thought I'd read somewhere that the WBUS was removed from the later D3 or D4 Webasto's.

Click to expand...

Not as far as I know it hasn't and iv been making and fitting these remotes to a few now. It's the big issue with them no w-bus signal no start that's why every one is using the thermotop C variant from earlier cars.

I'm just reading up on the L322 thermo top c as mines not working. I was under the impression that when the remote activates the FBH the FBH then sends a wakeup signal on the WBUS to the car. No idea if the D3 is the same. If it's a non WBUS FBH it will just start.

Iv got the aux ventilation built into the screen iv even set the timer and it all switches on then off at the programmed times BUT iv no fbh heater fitted. Was odd sitting in the car all shut down and hey presto it all came alive at the time I programmed it......obviously cold air comming out the vents tho.
Gonna look under ns wheel liner just to check if no fbh in there lol.
I'm sure there isnt I woulda noticed something like that

@biketeacherdave from what I have read
L322 WBUS controlled, 12v on pin 1 should wake up FBH which then wakes up car via WBUS (for park heater)
D3 CAN BUS contolled, WBUS control wire on early ones for park heater and diagnostics but removed on later ones, retrofit wire for WBUS control.

A number of us (me inc) are using the old rover units on camper conversions but the old unts PCD s are failing. Getting a canbus unit to run would be very usefull. If you make up a canbus signal board I think a lot of people would be keen to do the same. I have the WTT software and OBD for the old units and its clear that they are now just throwing PCB faults.

Can't you replace the board with one of these

https://www.ebay.co.uk/itm/DIESEL-A...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2648

Have a look on youtube, sure I have seen a vid where a guy made his own pcb board widget to control the heater as ecu died.
Arduino?
One of many,

Now that is interesting. I've done a lot of searching and never found that!

The L322 is canbus and the fbh are started by a switched positive, the D3 car is canbus but the fbh fitted in it is w-bus and requires a w-bus signal to start it hence why I had to purchase a w-bus PC to connect upto my remote 12v switching unit to get it to operate as and when I want ie usually 20mins before we use the car.

rob1miles said:

Now that is interesting. I've done a lot of searching and never found that!

Click to expand...

There are some clever feckers on there.

biketeacherdave said:

The L322 is canbus and the fbh are started by a switched positive, the D3 car is canbus but the fbh fitted in it is w-bus and requires a w-bus signal to start it hence why I had to purchase a w-bus PC to connect upto my remote 12v switching unit to get it to operate as and when I want ie usually 20mins before we use the car.

Click to expand...

From discussions with a FBH PCB repairer and the guy I got my WTT FBH diagnostic kit from this is my understanding, at least for the L322.
There are only 3 wires on the 6 way connector for the L322. Pin 1 goes to the Telestart remote module to receive a 12v start when the remote is pressed. Pin 2 is the WBUS. Pin 6 is the fuel pump. With the ignition on or via the timer with ignition off the L322 starts the FBH via the WBUS and alters the flaps on the air vents and switches on the fan. With the ignition off when the remote button is pressed 12v is applied to pin 1 the FBH then signals the car via pin 2 (wbus) to activate the flaps and fans. This is why you can't bench test a thermo top c from an L322, or use it in a standalone setup.

According to the D3 forum pin 2 is only wired on the early D3s so the later versions can't be WBUS controlled as standard.

Heater arrived today. Wires fitted to connector X1 are canbus, and fuel dosing pump. Thermotop V manual shows inputs on connector X1 for external temp switch (+ve ) and timer (-ve )
Ive rooted out the bits of coolant pipe left over from the navara install, hopefully theres enough left over. Need to buy a chinese dosing pump and get it set up on the bench, (once Ive cleared it yet again)

Edit. Note that Im using a D3 thermotop V to fit to a D2 which used a thermotop C, so its going to be a hybrid install. Not going to bother getting the atc panel to run, it can be done on the D2, (the atc panel
Is very similar to the rover 75) but from experience I havent found it necessary

Afraid not iv actually done this mod to our D3 on the early models ours is a 2005 the red wire is present so it's a simple splice into the existing red wire from the w-bus modual.
Like wise iv fitted the same units to later models where the red wire is not present, the answer is usually to purchase the red wire from the D3 shop and fit it into the plug. I didnt do that bit I just popped the little waterproof plug out and push the wire from the w-bus unit straight into the hole/pin 2.
On my L322 which is a 2003 v8 model I have the auxiliary ventilation built in to the car but no fbh. On setting the aux vent on timer it all comes on then off again when programmed but no heat due to the lack of a fbh nothing warms up. The L322 uses a thermotop C which is a activated by a simple switched 12 volts no canbus no w-bus.
Honest injun

It's pretty clear here

IMO the D3 WBUS is just for remote remote start, the actual FBH must be can bus controlled since the later ones do not have the WBUS connection (you have also said you have had to add it). Shiny Disco Balls diagram shows the can bus high and low pins.

With the L322 below 16 degrees the car operates the FBH, above 16 degrees it operates the ventilation. The FBH also has to be turned on in the CCF to operate. The 12v feed on pin 1 only goes to the telestart unit which only has a 12v feed and an earth, so can't be used by the car to start the FBH. The Thermo top c is used in lots of different cars and can be WBUS or not depending on the board fitted.
IMO the L322 is WBUS.

From RAVE

At a programmed parked heating/ventilation start time, or when parked heating/ventilation is selected on using the
MID/MFD, the instrument pack outputs:
l A parked heating/ventilation request to the MID/MFD on the I bus
l A parked heating/ventilation request to the ATC ECU and the Body Control Unit (BCU) on the K bus
l Ambient and engine temperatures to the ATC ECU and BCU on the K bus.
On receipt of the messages:
l The red LED on the MID/MFD panel flashes at 2 Hz to indicate that parked heating/ventilation is active
l If the ambient temperature is less than 5 °C (41 °F), the BCU activates the door mirror heaters for 3 minutes
l If parked heating is activated, the ATC ECU:
l Energises the changeover valve
l Sends a K bus message to activate the FBH
l Operates the blower at speed 1
l Opens the windscreen distribution flaps in the heater assembly and closes the face and footwell flaps.
l If parked ventilation is activated, the ATC ECU:
l Operates the blower at speed 1
l Opens the face level distribution flaps in the heater assembly and closes the windscreen and footwell flaps.


Parked Ventilation
Parked ventilation allows the vehicle interior to be ventilated with ambient air while parked with the engine stopped.
Vehicles without a FBH have parked ventilation only. On vehicles with a FBH, parked ventilation operates in
conjunction with parked heating (see Parked Heating/Ventilation below).

Nodge68 said:

Sorry I forgot.
I'll dig out the wiring today.

Click to expand...

Many thanks for that, as it's been in the minuses here over the last few days I can get the car de-iced/warm before I venture out. I only managed about 3/4 of an hour outside today on my D2 resurrection before me bones got to cold.

Chinese fuel dosing pump and fuel line have arrived. Waiting on a 2 pin plug and the remote so it can be bench tested. Tried it in its location but its oriented differently and in a different place on the D3 so its likely Ill have to fab up a mounting bracket

So my fbh turned up from the breakers with everything else I need to fit to my L322.
Plug on the fbh taken from a td6.
Muliplug only has x3 wires 2 of which are for the fuel dosing pump the other is a switched 12volt which is used to turn it on or off.

Will know soon enuf as I have everything now to run this up on the bench before I fit it.