O3 PTC heater retrofit

[Garpenlov]

Heya folks,

 

i'm trying to retrofit a PTC heater in my Octavia 3.

 

I was strugging with the following:

 

-which pins do i need for the ECU (1.8TSI) .

-which pins do i need for fuse holder B's fuses and relays?

 

Thank you kindly

 

[ApertureS]

For SB11 and SB12 you will need 2x 000979424E

 

For the engine ecu, you will need to show us exactly what pin point it is as the plug will use multiple sizes of terminal 

[Garpenlov]

Thank you kindly for your assistance!

Aren't those male connector?

I thought fuses would go in female connectors.

Just noticed they were the big square fuses. My apologies!

 

The ecu connector is a t94a (pin 47 & pin 90)

Edited 17 December, 2022 by Garpenlov

[ApertureS]

3 minutes ago, Garpenlov said:

Thank you kindly for your assistance!

Aren't those male connector?

I thought fuses would go in female connectors.

 

 

The ecu connector is a t94a (pin 47 & pin 90)

 

For J type slow plug fuses it uses male terminals and female sockets on the back of the fuses. 

 

For the engine ECU - please confirm this yourself!!!

But the plug part number is quite possibly 5q0906385 for the 94 pin and the terminals that fit this are 000979026E, 000979030E and 000979246E (these are all pigtail smallest wire sizes)

Heres a link to cross reference the pins https://docs.google.com/spreadsheets/d/1ABr4i_IWGl3KxmSV6Q51_fn2w9AO6C8tdG6cdbPowdk/edit#gid=0

[Garpenlov]

Thank you very kindly!
I will update this thread the moment all the parts arrive and i'll start on the build.

 

so that it becomes easier for others

[ApertureS]

3 hours ago, Garpenlov said:

Thank you very kindly!
I will update this thread the moment all the parts arrive and i'll start on the build.

 

so that it becomes easier for others

 

Do you have the PTC element? ive got a spare one i can sell you for very cheap

[Garpenlov]

Hmm it seems i may have to put this retrofit  aside, i just noticed there's no pins for the ECU on petrol models. 😞

[ApertureS]

18 hours ago, Garpenlov said:

Hmm it seems i may have to put this retrofit  aside, i just noticed there's no pins for the ECU on petrol models. 😞

There certainly is as my petrol 2.0 tsi has it fitted from the factory. On pin T91a/36

 

CORRECTION

 

On petrol engines May 2017 onwards it seems to go to the BCM J519 on pin T73c/52.

This is applicable to the superb though.

Before this date it seems it only went to the engine ecu, not bcm

 

 

ANOTHER EDIT

 

On the octavia it looks like High Heat Output Relay J360 is only suitable for diesel engines sadly.

Edited 18 December, 2022 by ApertureS

[Garpenlov]

Yeah i tried searching the relay names in the wiring schematics, but i only find them on diesel ECU's.

Quite the shame!

 

I could probably just hook it up to a manual switch, but i'm not sure if that's a safe thing to do.

[wirer]

any news regarding PTC fitting for gasoline engines? I don't have a 1.8, but only a 1.4TSI. I know the pin sizes, I just don't know which position in the motor RJ I should connect them to. so far I have it at 90 and 47, but the diagnostics reports an error and the PTC does not start 😞

[langers2k]

Looking at the factory WD, the connections vary by engine:

 

However, in the same document the connections are only listed for diesel engines which suggests petrol engines don't support PTC heaters.

 

It's not surprising, a petrol engine will probably warm up in 5-10 mins whereas a diesel may take 20-30 mins depending on outdoor temperatures.

[ApertureS]

1 hour ago, langers2k said:

Looking at the factory WD, the connections vary by engine:

 

However, in the same document the connections are only listed for diesel engines which suggests petrol engines don't support PTC heaters.

 

It's not surprising, a petrol engine will probably warm up in 5-10 mins whereas a diesel may take 20-30 mins depending on outdoor temperatures.

My petrol superb has the PTC heater  

 

Im getting rid of it though in favour of the auxiliary webasto heater 

[langers2k]

1 minute ago, ApertureS said:

My petrol superb has the PTC heater  

 

Interesting, I only have the Octavia WD so maybe the Superb WD can give some clues!

 

[ApertureS]

17 minutes ago, langers2k said:

 

Interesting, I only have the Octavia WD so maybe the Superb WD can give some clues!

 

I’ll try and see what’s in there tomorrow.

 

ECU and BCM should all be the same between octavia and superb so should all be there.

[EnterName]

10 hours ago, ApertureS said:

My petrol superb has the PTC heater  

 

Im getting rid of it though in favour of the auxiliary webasto heater 

Can you tell us what the options for speedy heat in a MK3 petrol Octavia are, @ApertureS?

Not for me, (edit: by that I mean I have heated seats and I'm toasty in the car) but without a heated windscreen, demisting takes a while, and if there are solutions to get warm air blowing fast, I'm interested to hear what the options are.

Edited 17 November, 2023 by EnterName

[wirer]

I have a scheme for TDI engines, but I secretly hope that it will be possible to connect it for TSI engines as well.

In my opinion, the units for the engine will be similar, but I also looked at the Golf TSI, for example, there is no connection option there either