datsundrew
A2OC Donor
Was it a real nightmare job?
Auxillary heater
- Thread starter Taylor
- Start date
2work
Well Known Member
Evening,
I clearly cannot answer for Paul here but know he is very capable in many areas of the A2. Quite sure he wound ace the next dashboard swap when next presented with such a task.
In my limited experience though from initially reading the available guidance here on the clubs pages along with minimal input from various members before removing my first dashboard, I can report that’s it’s not the easiest of tasks for sure but totally achievable with a basic set of tools and a good understanding of how to remove some of the interior panels. Many members have completed this task themselves in 4 hours (2 hours removal followed by 2 hours refitting) or less. In the last couple of years I think I’ve removed 7 dashboards and refitted 4 double DIN dashboards to my own fleet. I would say that I’d prefer to do this task on a fair weathered/warm Saturday during the months with more daylight than we’re experiencing right now. That said I did 2x single DIN removals followed by 2x double DIN installations almost back to back one festive period. I’d rather not repeat that amount of work again so closely scheduled together, but would of course if it was necessary as the self satisfaction afterwards was priceless and very rewarding.
In short; totally achievable but very much dependant on ability, experience levels and of course understanding the pieced together knowledge gained from all available sources.
I’d be more than happy to remotely assist over PM or video call to ensure you’re heading in the right direction but only if you felt comfortable in taking this type of task on. Just remember that if you’re halted by a hurdle which you cannot conquer then you’re pretty much going to loose the ability to use the vehicle until a helping hand could get to you. It could just be one of those jobs you outsource to someone who’s a dab hand at it already, there is quite a few of us about these days.
As much as I’m fairly confident as quite a few things these days and don’t mind getting my hands dirty, I’d much rather repeat the 2x dashboard removals and 2x dashboard installations back to back than removing 4 wheels arch liners then refitting them. I know the wheels arch liners are a simple and much quicker operation but it’s just task I really dislike for some reason. Some people prefer the more intricate tasks I suppose.
PM me if you ever get stuck or need any advice.
Kind regards,
Tom
depronman
A2OC Donor
Put it this way I won’t be removing two dash boards and two different A2’s and fitting them in opposite cars in the same day again
Paul
Sent from my iPhone using Tapatalk
George Hogg
A2OC Donor
Hi Graham, yes I know that but I don’t know where that comment came from. The heaters don’t work on those 90s and a 75 but they do on the other 90 and 75s. It’s apparently a map issue
2work
Well Known Member
Morning Graham,
If my understanding is correct; all the TDI ECUs were coded as 00002 at the factory which is why the heaters work if there aren’t any underlying issues. Those of us who have struggled to get their heaters to fire up have had a remap at some point due to the software coding being changed to 00005.
This 00005 software coding has been implemented by the person conducting the remap. It’s great that this has come to light now so we can simply switch between the 2 maps to get the auxiliary heater to work in the colder months then return to the fuller powered map after the early spring frosts.
Quite happy to be corrected but from going back over historical logs, I know my ECU coding (OEM, 250 and EUD) was 00002 before I removed it to be checked over by Paul.
Hope that makes sense Sir.
Kind regards,
Tom
Hi George,
Clearly I have caused some unintended offence, for that I apologise. Reading my post #16 back I see that including your name as an example was unnecessary and I should have said "someone" rather than "@George Hogg". I was just trying to benefit other users with the information I provided about the ECON button. Since in your post #14 you stated that non of your TDI90's heaters worked, my intellectual sloth linked my thought with you. I am aware you are a long standing member of the club with much experience and I should have realised you already knew how the ECON button (also on the climate version) worked and it's effect on the electric heater.
I would be interested to know to which "map" you are referring, particularly if its the coolant temperature map. Due to running on veg oil, on a cold start my temperature map is reprogrammed to tell the ECU it is minus 30C coolant temperature rather than reality (the temperature differential is blended back to reality as the coolant warms up). However I still suspect the PTC heater only works at 6C or below (and with "ECON" button off!), though as I've stated in post #16 I'm never completely sure.
If the ECU uses the external temperature signal, as I suspect, then it might be possible to install a resistor that can be switched into the external temperature feed to fool the ECU into allowing the PTC heater to work at temperatures above 6C, though CANBUS might thwart that plan. I'm familiar with VCDS but have never discovered anywhere in there that can change the 6C value.
Respectfully
T
So I'm going to ask the dumb question here. Is the software coding to which you refer (00002, 00005) switchable with VCDS, or are you referring to the use of a read/write tool like MPPS?
2work
Well Known Member
Not a dumb question at all,
If you don’t know the answer, which is of course your reason for asking then it’s a totally valid question.
The answer is quite simple: Yes switch between Engine 01s Software coding from 00005 to 00002 and back as you see fit with VCDS. No need to read/write and EEPROM values.
I cannot say if VCDS Lite or unregistered versions work as have only done this with a genuine register unlimited VIN cable. I’m sure some of the other diagnostics tools available might well be able to do this also.
Hope this helps.
Kind regards,
Tom
PlasticMac
Member
Registered Lite does it.
Mac.
2work
Well Known Member
Thanks for confirming Mac,
Always good to know what software iteration can help out in these situations as more of us now need to switch this coding around throughout the year.
Kind regards,
Tom
PlasticMac
Member
There's very little, (nothing that I'm aware of), that registered Lite can't do on pre 2005/06 cars.
Mac.
George Hogg
A2OC Donor
It is to do with some ECU remaps, some apparently lock out the ancillary heater either webasto or electric. It can be mapped back in. I’m not sure how much of that we’re allowed to discuss on remaps.
That’s the 00002/00005 issue
The temp at which the heaters switch out can be changed but I’m not smart enough to know the detail.
Thanks for that.
I'd be very interested in raising my PTC heater maximum operational air temperature from 6C to say 12C if anyone can tell me how. I have VCDS. I appreciate this will reduce the economy of the car marginally but I do very many cold starts between these temperatures where I would appreciate instant warmth. It would also heat the coolant a little quicker due to the extra load on the engine from the alternator and less heat draw from the coolant. If I want more economy all I'd need do is turn the ECON button on.
Joga
A2OC Donor
Not that it will be of huge interest to the UK member who scarcely come in contact with the legendary 3L version, but to see the complete version I can chip in the observation:
1. no 1.2TDI have webasto (at least to my knowledge ) .
2. many have PTCs
3. some have no additional heater at all!
I have one of the latter, brrrr.
PlasticMac
Member
Don't underestimate the effect of continously drawing around 75 amps to power the 900 Watts of heat.
It may not be instant either, after a cold start, with lights and rear screen heater on, the system voltage may take a while to recover to the point where the ECU will enable the PTC heater.
Mac.
Yes the PTC would be on more often than with the current 6C cut off but wouldn't exactly be continuous. The PTC would still switch off when either the cabin or coolant was warm enough, which would be sooner than with a 6C cut off.
I heed your warning. The alternator and battery have been specified to match the requirements of the PTC heater. But colder climates would use the PTC more frequently and that's all I'm really trying to achieve. That is, more frequent use of PTC, not a colder climate!
I heed your warning. The alternator and battery have been specified to match the requirements of the PTC heater. But colder climates would use the PTC more frequently and that's all I'm really trying to achieve. That is, more frequent use of PTC, not a colder climate!
PlasticMac
Member
The ECU will protect the battery by not enabling the heater unless it can be fully supplied by the alternator, whilst still charging the battery. The ECU monitors the alternator load, and will disable the PTC, when, (or until), the total power demand, including the PTC, is less than 100% of the alternator's capacity.
Mac.
Mac.