F125 Switch or TCU - or something else?

4.2 V8 40v biturbo - 450 bhp
4.2 V8 40v biturbo - 480 bhp (plus)
airtite
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Re: F125 Switch or TCU - or something else?

Post by airtite » Tue Nov 16, 2021 7:01 am

Thanks Matt, mine has gone from bad to worse after a sprited drive yesterday parked the car at home and tried to start a little later now the prnds light stays on and I cant clear code as soon as I clear it it comes straight back and the now the car wont even start.... brake lights are working but the brake light is not showing next to the gear lever.

airtite
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Re: F125 Switch or TCU - or something else?

Post by airtite » Tue Nov 16, 2021 7:50 am

A little concerned that I cant start the car at all now.

airtite
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Re: F125 Switch or TCU - or something else?

Post by airtite » Tue Nov 16, 2021 8:12 am

nevermind... I swear lately it just feels like I am a complete idiot. The connector for the f125 was loose after I cleaned it. Car starting again but the f125 still needs to be replaced.

airtite
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Re: F125 Switch or TCU - or something else?

Post by airtite » Tue Nov 16, 2021 10:20 am

can we confirm that ours is in fact a 10pin connector?

HPsauce
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Re: F125 Switch or TCU - or something else?

Post by HPsauce » Tue Nov 16, 2021 11:00 am

Surely you saw the connector when you cleaned it? :bash:
Anyway, the old 9-pin connector is round, the newer one is rectangular-ish with one rounded end. (And only uses 9 of the 10 pin slots)

airtite
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Re: F125 Switch or TCU - or something else?

Post by airtite » Tue Nov 16, 2021 11:34 am

HPsauce wrote:
Tue Nov 16, 2021 11:00 am
Surely you saw the connector when you cleaned it? :bash:
Anyway, the old 9-pin connector is round, the newer one is rectangular-ish with one rounded end. (And only uses 9 of the 10 pin slots)
I did see it just was confused about the "(And only uses 9 of the 10 pin slots)" thanks

Mɐʇʇ
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Re: F125 Switch or TCU - or something else?

Post by Mɐʇʇ » Tue Nov 16, 2021 11:39 am

I posted the part number you need on page 1. And Also a linky to the parts website so you can double check the part number yourself.

Where people have got this "8-pin round plug" idea from?
"not a professional engineer, mechanic and mechanist"

airtite
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Re: F125 Switch or TCU - or something else?

Post by airtite » Tue Nov 16, 2021 11:46 am

Mɐʇʇ wrote:
Tue Nov 16, 2021 11:39 am
I posted the part number you need on page 1. And Also a linky to the parts website so you can double check the part number yourself.

Where people have got this "8-pin round plug" idea from?
Yup used that part number and on ecstuning they make mention of 10 pin then found one on amazon which says 9 pin both plugs look the same.

Mɐʇʇ
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Re: F125 Switch or TCU - or something else?

Post by Mɐʇʇ » Tue Nov 16, 2021 12:12 pm

Can you show me the amazon link? Anyway, the ifinterface linky I gave, plus the odd other link (Ben uses a different site, for example) are basically the bible.

To the extent that I've bought parts based on part number before even when the ECP or whatever parts guide doesn't show it as fitting - they're not very reliable anyway. They even get the oil spec wrong for our cars sometimes. So I only ever buy off part number and sometimes, if you order off Audi based on part number, they assume you're trade and give you some discount - I have had that before occasionally. ;)
"not a professional engineer, mechanic and mechanist"


Mɐʇʇ
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Re: F125 Switch or TCU - or something else?

Post by Mɐʇʇ » Tue Nov 16, 2021 12:49 pm

Irrespective of part number, that's showing the rectangle connector, which is correct.
Now, "maybe", if O1L goes NLA, 01V could also be compatible - for example, on handbrake cables some members worked out you can use a different part number.

But 01L is what you want, and buy the OEM one. It's a part that is so much aggro to change if you bought "unknown" aftermarket and it didn't work properly.
"not a professional engineer, mechanic and mechanist"

airtite
2nd Gear
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Re: F125 Switch or TCU - or something else?

Post by airtite » Tue Nov 16, 2021 12:52 pm

Mɐʇʇ wrote:
Tue Nov 16, 2021 12:49 pm
Irrespective of part number, that's showing the rectangle connector, which is correct.
Now, "maybe", if O1L goes NLA, 01V could also be compatible - for example, on handbrake cables some members worked out you can use a different part number.

But 01L is what you want, and buy the OEM one. It's a part that is so much aggro to change if you bought "unknown" aftermarket and it didn't work properly.
pulling the motor and will be modifing the mount so I can change it easily in the future... the exchange rate here makes the oem one quite expensive and cash is a litlle tight at the moment.... just had to replace the Diesel pump on my q7 as well.

HPsauce
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Re: F125 Switch or TCU - or something else?

Post by HPsauce » Tue Nov 16, 2021 12:57 pm

airtite wrote:
Tue Nov 16, 2021 11:34 am
was confused about the "(And only uses 9 of the 10 pin slots)"
It's a fairly common weather-resistant VAG connector design that allows for up to 10 pins. The F125 only uses 9 of them, one pin is missing, IIRC number 6.

airtite
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Re: F125 Switch or TCU - or something else?

Post by airtite » Tue Nov 16, 2021 12:59 pm

HPsauce wrote:
Tue Nov 16, 2021 12:57 pm
airtite wrote:
Tue Nov 16, 2021 11:34 am
was confused about the "(And only uses 9 of the 10 pin slots)"
It's a fairly common weather-resistant VAG connector design that allows for up to 10 pins. The F125 only uses 9 of them, one pin is missing, IIRC number 6.
understood

Duke Thrust
Neutral
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Re: F125 Switch or TCU - or something else?

Post by Duke Thrust » Wed Nov 17, 2021 5:35 pm

Interesting the potential options here, this one lists the RS6 (03-04) as a fitting:

https://www.ebay.co.uk/itm/01V919821-B- ... P0QAvD_BwE

I get the quality concerns (and I'm very new to RS6 ownership) - but if the gearbox mount can be modified to allow quick replacement, then this could be a viable option even if it lasts just 40 or 50k. (Audi said they only had 5 left in stock)

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