Hi all! I'm a bit of a novice to this, so please bear with me.
Now that the weather in the UK has finally dropped below 10 degrees C, I fired up my camper conversion base vehicle to see how well the Webasto Top C Auxilliray coolant heater worked. Nothing, no noise and the engine took a long time to heat up.
I decided have a read with VCDS. There are no fault codes stored for 18 - Aux heating and a full scan only shows an error for the radio, as I've changed it for a non VW head unit. Running the sequential output tests on 18 -Aux Heating usually works and goes though all tests. I can hear the heater fire up, the only odd thing was that even though the recirculating pump test seems to produce a noise and comes up green, it's duty cycle stays at 0.0%.
If I go back in to test again, sometimes it gives an error along the likes of "not all pre requisites met" or similar, but I do here it fire up. On shut down of the engine, it carries on working as it should and everything seems normal.
Now the previous owners were a private hire firm, who rented it out as a 9 seater Shuttle bus. Because of this, I wondered if they had somehow disabled it with VCDS or some other diagnostic software, due to customers phoning them up alarmed that there was a noise and diesel fumes after turning off the engine.
In the measuring blocks I've seen 10 degrees C mentioned, so am guessing the activation temperature has not been lowered from standard.
Does anyone know of a way I can find out why the unit doesn't come on unless prompted by VCDS?
I read somewhere on the Ross Tech wiki about disabling the system on a similar car, in "Adaptations" > "Group3" by changing the 1 to a 0. I've tried changing the 0 visible in my Group3 to a 1, clicked "Test", then "Save". I get prompted to ask if I want to change the 0 to a 1. I click yes, but when I go back in the value is still a zero.
I have half a tank of fuel, the battery has been charged, A/C is off and even with the bus started on my driveway, with the dash reporting under 10 degrees C, it does not fire up the aux heater.
Many thanks, Marcus
Now that the weather in the UK has finally dropped below 10 degrees C, I fired up my camper conversion base vehicle to see how well the Webasto Top C Auxilliray coolant heater worked. Nothing, no noise and the engine took a long time to heat up.
I decided have a read with VCDS. There are no fault codes stored for 18 - Aux heating and a full scan only shows an error for the radio, as I've changed it for a non VW head unit. Running the sequential output tests on 18 -Aux Heating usually works and goes though all tests. I can hear the heater fire up, the only odd thing was that even though the recirculating pump test seems to produce a noise and comes up green, it's duty cycle stays at 0.0%.
If I go back in to test again, sometimes it gives an error along the likes of "not all pre requisites met" or similar, but I do here it fire up. On shut down of the engine, it carries on working as it should and everything seems normal.
Now the previous owners were a private hire firm, who rented it out as a 9 seater Shuttle bus. Because of this, I wondered if they had somehow disabled it with VCDS or some other diagnostic software, due to customers phoning them up alarmed that there was a noise and diesel fumes after turning off the engine.
In the measuring blocks I've seen 10 degrees C mentioned, so am guessing the activation temperature has not been lowered from standard.
Does anyone know of a way I can find out why the unit doesn't come on unless prompted by VCDS?
I read somewhere on the Ross Tech wiki about disabling the system on a similar car, in "Adaptations" > "Group3" by changing the 1 to a 0. I've tried changing the 0 visible in my Group3 to a 1, clicked "Test", then "Save". I get prompted to ask if I want to change the 0 to a 1. I click yes, but when I go back in the value is still a zero.
I have half a tank of fuel, the battery has been charged, A/C is off and even with the bus started on my driveway, with the dash reporting under 10 degrees C, it does not fire up the aux heater.
Many thanks, Marcus
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