OEM Webasto Auxiliary Heater To Parking Heater Upgrade

[mmi]

read that the overhead control/display has 4 connections, not 6.

Yes, 4 is correct for the parking (coolant) heater (2 for CAN, + 2 for the power).
Your wiring diagram is for the auxiliary air heater.

 

[Vanarama]

Thanks for your reply.

Is the CAN bus connection only for the coolant heater and the 4 non-CAN cables are for the Airtronic air blower?

Ie. There are 2 almost separate systems, or is the CAN bus used to coordinate combined operation?

Sorry if they seem like daft questions.

Thanks

 

[eugene]

Thanks for your reply.

Is the CAN bus connection only for the coolant heater and the 4 non-CAN cables are for the Airtronic air blower?

Ie. There are 2 almost separate systems, or is the CAN bus used to coordinate combined operation?

Sorry if they seem like daft questions.

Thanks

Air heater and water heater remotes work differently.
In case of water heater, CAN wires are connecting the remote to the car and controlling the heater via CAN.
In case of air heater, the CAN is used only to connect the remote to the car. The rest of the wires are used for controlling the heater by the remote.
Hope it makes sense.

What are you trying to achieve?

 

[Vanarama]

Thank you for your reply @eugene .

I have an almost complete set of parts including the coolant heater and the air heater. They date from around 2016, but are very good condition.

I am working on fitting them to a 2020 model.

I have studied the diagrams and I am piecing togther the missing information.

Ideally I would like to fit the air heater part and then later the coolant part.

However I realise that they have some crossover - eg, the harness between the blue (right vehicle side) and red connector (left vehicle side).

So fitting separately might not be realistic.

The remote control feature is secondary to me at this stage / not bothered.

I'm basically understanding how it works so I can weigh-up my options.

Thanks

 

[eugene]

Thank you for your reply @eugene .

I have an almost complete set of parts including the coolant heater and the air heater. They date from around 2016, but are very good condition.

I am working on fitting them to a 2020 model.

I have studied the diagrams and I am piecing togther the missing information.

Ideally I would like to fit the air heater part and then later the coolant part.

However I realise that they have some crossover - eg, the harness between the blue (right vehicle side) and red connector (left vehicle side).

So fitting separately might not be realistic.

The remote control feature is secondary to me at this stage / not bothered.

I'm basically understanding how it works so I can weigh-up my options.

Thanks

I am almost certain you already have a water heater. Please check it.
Air heater from 2016 won't be compatible with 2020 car. I think connecting it to a remote will still be possible but it won't talk to the car.
So I suggest you make a harness for the air heater including the CAN wires. If this brings a load of errors, you will disconnect the CAN wires and just use the remote to control the heater.

I think it will be an interesting project.

 

[Vanarama]

Thanks @eugene

Yes I do have the coolant and the air heater.

Thank you for your ideas.

I will investigate further.

The set came with:
Matching centre roof display/control unit
Webasto coolant heater+ pipes
Eber air heater
Trims
Ducts
Pumps
Etc

Regards