Factory Stationary heating system retrofit
Thread Starter
MBWorld Fanatic!
Joined: May 2003
Posts: 4,005
Likes: 106
From: Houston, TX
2015 E250D
Factory Stationary heating system retrofit
Stationary heating is not available on the USA. Webasto manufacturers a heating unit that Mercedes’ uses for cold climate countries. The unit fits under the front right headlamp assy. It uses fuel from the tank to ignite a burner element that heats coolant. This warm coolant is circulated to warm the engine and interior cabin. I will break down installation into three stages.
1. installation of wiring
2. installation of fuel lines
3. installation of coolant lines.
the system itself is activated one of several ways.
1. preset timer in instrument cluster. The instrument cluster will allow three preset times to activate the heater
2. remote control with bidirectional communication
3. button under comand system
4. third party cellular based activation.
Regarding wiring, I ordered a w204 chassis wire since w212 is not available. The wire harness works perfectly for the w212 chassis. I ran it from the rear right Sam unit to the right front of car. I did this at the same time as running wiring for distronic.
1. installation of wiring
2. installation of fuel lines
3. installation of coolant lines.
the system itself is activated one of several ways.
1. preset timer in instrument cluster. The instrument cluster will allow three preset times to activate the heater
2. remote control with bidirectional communication
3. button under comand system
4. third party cellular based activation.
Regarding wiring, I ordered a w204 chassis wire since w212 is not available. The wire harness works perfectly for the w212 chassis. I ran it from the rear right Sam unit to the right front of car. I did this at the same time as running wiring for distronic.
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Joined: Apr 2019
Posts: 11,957
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
this heater retrofit will come in handy during winter storms.
How does the heated coolant get circulated throughout... small electric pump powered by main battery.
The engine electric thermostat will remain shut without ECU control saving heat from escaping to radiator.
How does the heated coolant get circulated throughout... small electric pump powered by main battery.
The engine electric thermostat will remain shut without ECU control saving heat from escaping to radiator.
Thread Starter
MBWorld Fanatic!
Joined: May 2003
Posts: 4,005
Likes: 106
From: Houston, TX
2015 E250D
this heater retrofit will come in handy during winter storms.
How does the heated coolant get circulated throughout... small electric pump powered by main battery.
The engine electric thermostat will remain shut without ECU control saving heat from escaping to radiator.
How does the heated coolant get circulated throughout... small electric pump powered by main battery.
The engine electric thermostat will remain shut without ECU control saving heat from escaping to radiator.
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2015 E250D
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2015 ML400 4MATIC, 2016 C300 4MATIC, 2014 E350 4MATIC (Totaled), 2006 E350 (Sold)
Thread Starter
MBWorld Fanatic!
Joined: May 2003
Posts: 4,005
Likes: 106
From: Houston, TX
2015 E250D
Thread Starter
MBWorld Fanatic!
Joined: May 2003
Posts: 4,005
Likes: 106
From: Houston, TX
2015 E250D
Initial startup will be done once fuel line is installed.
Initial connectivity using xentry shows the module is visible with current firmware installed.
Started installation of all coolant lines. First drained all coolant at pet **** on driver side.
New silver line connected to black hose from heater core connection under wiper motor
Running this line along firewall was painful
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C238
Stationary heating is not available on the USA. Webasto manufacturers a heating unit that Mercedes’ uses for cold climate countries. The unit fits under the front right headlamp assy. It uses fuel from the tank to ignite a burner element that heats coolant. This warm coolant is circulated to warm the engine and interior cabin. I will break down installation into three stages.
1. installation of wiring
2. installation of fuel lines
3. installation of coolant lines.
the system itself is activated one of several ways.
1. preset timer in instrument cluster. The instrument cluster will allow three preset times to activate the heater
2. remote control with bidirectional communication
3. button under comand system
4. third party cellular based activation.
Regarding wiring, I ordered a w204 chassis wire since w212 is not available. The wire harness works perfectly for the w212 chassis. I ran it from the rear right Sam unit to the right front of car. I did this at the same time as running wiring for distronic.
1. installation of wiring
2. installation of fuel lines
3. installation of coolant lines.
the system itself is activated one of several ways.
1. preset timer in instrument cluster. The instrument cluster will allow three preset times to activate the heater
2. remote control with bidirectional communication
3. button under comand system
4. third party cellular based activation.
Regarding wiring, I ordered a w204 chassis wire since w212 is not available. The wire harness works perfectly for the w212 chassis. I ran it from the rear right Sam unit to the right front of car. I did this at the same time as running wiring for distronic.
Thread Starter
MBWorld Fanatic!
Joined: May 2003
Posts: 4,005
Likes: 106
From: Houston, TX
2015 E250D
I'm not sure how your system in Sweden but yes you can cheat the system. I assume you have to disconnect the valve but I'm not sure if it will throw an error code.
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Mercedes-AMG CLS 63 S 4MATIC
