Finally retrofitted timer to the heater
In the last few days I have been busy with retrofitting a timer and a GSM-unit to the additional heater on my beloved A2. After a lot of preparation, going over the installation manuals and studying it closely, it was time to get to work. Disassembling cover panels and glove box was easy. Getting to the power near the ECU; easy. Fitting the circulation pump: easy.
I knew that my Webasto had stopped working again before I started, so I had to take it out of the car for cleaning. This was not so easy. It is quite hard to get the tools in place, and the clamps for the hoses are a bit tricky to get of if the tools cant get to it. So I used my Dremel-tool with an extension cord and cut them of. I later replaced the clamps with new ones. Once the heater was out, I cleaned the glow plug. Then my brother who works with diesel engines and heater systems took a closer look at the burner element. It was completely charcoaled and we gave it a cleaning with a brass brush attached to the Dremel tool. Now it was time to put it all back together.
The wiring bundle has a relay and to fuse holders. From this a lead with a black and a white/green goes to the 6-pin socket on the heather. I had to remove the air intake, the sensor cluster for the turbo an a thin ALU heat shield to get to the place where the wires goes from the booth to the engine room. Fairly straight forward.
Black wire to pin 1 on heater (This gives a signal from the timer to start the heater)
Green/white wire to pin 4 on heater (This gives the relay the start signal to start the interior fan and optionally there is a single green/white wire to pin 10 on the Climate Control unit. If there is no climate control, isolate and ignore it.)
Done with wires to the heater.
Next, the wires to the interior fan. The 6-pin connector on the fan contains a green/red wire. Pull it out and connect it to the red wire on the red and black pair. The black wire goes in to the slot where the green/red came out of.
Done with the wires to the interior fan.
Next, connect the brown wire to the ground point near the relays at the lower A-pillar area. Stretch the single red cable all the way to the ECU-area, connect it to the fuse from the kit and then to the plus power. (BTW, disconnect the battery BEFORE doing anything).
Done with power supply.
Find a good place for the timer and connect the last wire bundle to it.
Done! Lets fire it up.
WTF??? The fan on the heater starts up, but it does not start. Well, i didn't honestly think it would go smoothly. My brother and I started troubleshooting. We noticed that the relay didn't get any signal, and the metering pump (fuel pump) did not get power. OK, we took out the pump and checked it. After some fiddling we deduced that the pump works fine. We took some pressured air and blew through the fuel line. There were some dirt, but we cleaned it out. Hmmm. Still no go. We searched several forums on the topic, and someone mentioned that the outdoor temp sensor had to be cooled down. I grabbed a shovel and found some snow and packed the sensor. Still nothing. Only the air blower would run, but no fire. Maybe the controller unit inside the heater was broken? The unit is suppose to send the signal to the pump and relay, but nothing is being sent. Hmmmm....
After a good Christmas dinner and some searching on the web, I decided to hook up my Vag-Com and see if there was any fault-codes that needed to be cleared. Nah... nothing. Then we asked ourselves: Why isn't the heater getting fuel? We pealed of the fuel hose on the heater and used the Vag-Com to start the metering pump.
*Golden Vag-Com tip: 18. Aux. Heating => 3. Output tests => Start
Yes! The pump primed the fuel line and we were getting fuel all the way to the heater.( Had to do this 3 times before fuel came out up at the burner.) Then we took pressured air to the fuel intake on the heater. Sh**! Completely clogged. I sprayed in some WD-40, waited a few minutes and pressed 8 bar of air to the intake. Poff! Success. Now the heater was open again! We assembled it and used Vag-Com to start the heater manually.
*Vag-Com tip: 18. Aux. Heating => 4. Basic tests => Group 22 => Go!
Woha!! The heater started to prime and burn at once.
This story is not only about retrofitting a timer, but also to revive at dead heater.
At the end I fitted the Thermo Call Connect 2 unit with GSM antenna and programmed it.
Easy part.
Feel free to ask for more details. Unfortunately I didn't take pictures...