TDI electric heater

Chris93

Member
Hi all, I seem to recall in my last a2 the interior heated up quickly in the winter when ECON wasn’t on due to an electric heater.

In my current a2 there is no heat for quite some time even with ECON off so I don’t feel like this is working. Is this a common issue and is it easy to fix/replace?

thanks
 
Is the blower working? Other causes could be flaps not working or blown fuses.

RAB
 
Early Diesel cars have a Webasto heater which I am told works very well. Later cars dispensed with it. The water circuit does divert water to the heater circuit initially, on my old TDi the cabin was being warmed before the temp gauge moved off the cold stop.
 
On my 2003 the electric heater only seems to work in screen-defrost mode (top left button). It starts heating literally seconds after starting and the fan goes to about half way on the screen. If I then de-select the screen, the fan drops right back until I've driven a couple of miles, then gradually increases in line with available coolant temperature vs the interior.

Anyway, with the above in mind I simply pop it onto defrost and leave it there until I reckon I've driven far enough to take advantage of the regular heating. Also, this weekend I'm hoping to fit my Chinese bum-toasters!
 
Or too high a load on the alternator.
True but the heater will be the major consumer. If it doesn't come on at start-up, it has no use!

RAB
Is the blower working? Other causes could be flaps not working or blown fuses.

RAB
Check the J360 (heater relay). position 4 in the 9-relay holder.

RAB
 
On my 2003 the electric heater only seems to work in screen-defrost mode (top left button). It starts heating literally seconds after starting and the fan goes to about half way on the screen. If I then de-select the screen, the fan drops right back until I've driven a couple of miles, then gradually increases in line with available coolant temperature vs the interior.
At most, it's only a 1500w heater (only 900w in some variants, e.g. 1.2Tdi), so it won't have a huge impact. It's main use would be for defrosting; it should turn off when the coolant gets up to temperature.

RAB
 
At most, it's only a 1500w heater (only 900w in some variants, e.g. 1.2Tdi), so it won't have a huge impact. It's main use would be for defrosting; it should turn off when the coolant gets up to temperature.

RAB
It actually makes a real difference: amazingly so. I wouldn't want to be without it anyway.
 
@Chris93 , don't think anyone's checked that you do have a diesel?

As I recall, only the diesels were fitted with the webasto, then latterly with an electric heater to replace the webasto.

I seem to think that the webasto only kicked in at 7c ambient temp and below (sure someone will correct me here...). Not sure when they transitioned from the webasto to electric though, but any diesel at 2005 would be electric..
 
So I have an update here! And yes my car is a diesel.

Cars post 2003 (ish) have an electric auxiliary heater rather than a Webasto, couldn’t figure out why mine wasn’t kicking in but i have had a dodgy coolant temp sensor which has been working on and off. I had that replaced yesterday and all of a sudden the temp drops below 5 degrees and instant heat on startup it does work!

Check your coolant temp sensor is working properly as I believe it has to Log the coolant is Below 60 degrees for the electric heater to kick in and mine was obviously not reading anything to the ECU.

Hope that helps someone with the same issue
Chris
 
So I have an update here! And yes my car is a diesel.

Cars post 2003 (ish) have an electric auxiliary heater rather than a Webasto, couldn’t figure out why mine wasn’t kicking in but i have had a dodgy coolant temp sensor which has been working on and off. I had that replaced yesterday and all of a sudden the temp drops below 5 degrees and instant heat on startup it does work!

Check your coolant temp sensor is working properly as I believe it has to Log the coolant is Below 60 degrees for the electric heater to kick in and mine was obviously not reading anything to the ECU.

Hope that helps someone with the same issue
Chris
Is this the sensor at the bottom of the radiator OR the one inside coolant bottle/reservoir in the engine bay ? which did you change, I have the same issue having changed the thermostat, car warms up very quickly but the gauge sits at zero.
Cheers,
Ami
 
Is this the sensor at the bottom of the radiator OR the one inside coolant bottle/reservoir in the engine bay ? which did you change, I have the same issue having changed the thermostat, car warms up very quickly but the gauge sits at zero.
Cheers,
Ami
The 1.4Tdi coolant temp sensor (dual supply to ECU and dashboard respectively) is on the (UK) passenger side of the engine block directly underneath the tandem pump. To get to it easily you need to take off the L-shaped boost return pipe and usually a metal plate that carries the loom for the temp sensor and various other things which is held in place using a 10mm nut - this at least means you can get to the sensor with hands and a pair of 90 degree pliers to release the plastic U-clip that holds it against the o-ring in the housing. Good daylight from the right angle or a head torch are incredibly helpful - I tried and failed to perform the swap twice before I got a day with mid-morning sunlight over my shoulder that illuminated the area perfectly and made the job so much easier - ironically having done it once like that I've done it again a couple of weeks ago on my project car under sub-ideal conditions without too much difficulty barring encountering a bendy non-original clip - which suggests as a DIY-er this is one that relies on confidence and a bit of muscle memory rather than actual skill or tools.
 
  • Like
Reactions: Ami
The 1.4Tdi coolant temp sensor (dual supply to ECU and dashboard respectively) is on the (UK) passenger side of the engine block directly underneath the tandem pump. To get to it easily you need to take off the L-shaped boost return pipe and usually a metal plate that carries the loom for the temp sensor and various other things which is held in place using a 10mm nut - this at least means you can get to the sensor with hands and a pair of 90 degree pliers to release the plastic U-clip that holds it against the o-ring in the housing. Good daylight from the right angle or a head torch are incredibly helpful - I tried and failed to perform the swap twice before I got a day with mid-morning sunlight over my shoulder that illuminated the area perfectly and made the job so much easier - ironically having done it once like that I've done it again a couple of weeks ago on my project car under sub-ideal conditions without too much difficulty barring encountering a bendy non-original clip - which suggests as a DIY-er this is one that relies on confidence and a bit of muscle memory rather than actual skill or tools.

That’s the one! :)
 
The 1.4Tdi coolant temp sensor (dual supply to ECU and dashboard respectively) is on the (UK) passenger side of the engine block directly underneath the tandem pump. To get to it easily you need to take off the L-shaped boost return pipe and usually a metal plate that carries the loom for the temp sensor and various other things which is held in place using a 10mm nut - this at least means you can get to the sensor with hands and a pair of 90 degree pliers to release the plastic U-clip that holds it against the o-ring in the housing. Good daylight from the right angle or a head torch are incredibly helpful - I tried and failed to perform the swap twice before I got a day with mid-morning sunlight over my shoulder that illuminated the area perfectly and made the job so much easier - ironically having done it once like that I've done it again a couple of weeks ago on my project car under sub-ideal conditions without too much difficulty barring encountering a bendy non-original clip - which suggests as a DIY-er this is one that relies on confidence and a bit of muscle memory rather than actual skill or tools.
Cheers for that, I shall have a go at Xmas holidays.:)
 
Back
Top