Audi TT wading depth

[Nick Jones]

3 hours ago, andymcp said:

Do you need the correct diagnostic software to bleed the ABS system correctly?

 

 

Yes. But this is only ever an issue if air has got into the system upstream of the ABS pump (changing the MC would definitely create that problem for example), otherwise it’s just bleed as normal and take care not to let the reservoir get low.

[Nick Jones]

So….. it’s been mostly behaving. I did change the oil and filter, including a dose of engine flush beforehand.  Also went from 5/30 (piss!) to 10/40. Doesn’t seem to be using much now. It’s also doing more (alot more) miles now its keeper has “retired”!

She did complain of random warning lights on the dash a week or two back.  It is a VAG product after all.  She even managed to photograph one of them. That was the bulb checker telling her a brake light is out. The other was the traction control light.

They kept coming and going, never on at home. Brake lights all appeared to work whenever tested. In the end I removed the LH light cluster and changed the bulb anyway. It was working at the time but did look odd where the filament joined the post. Also scanned for codes which turned up “brake pressure transducer 1/2 implausible value”.  I just reset that…..

No more warning lights…… Apparently failed bulbs can trigger phantom warnings in ABS/traction control systems…. 

[Escadrille Ecosse]

2 hours ago, Nick Jones said:

brake pressure transducer 1/2 implausible value”.  I just reset that.....

Was that to a plausible value or just a fully implausible one? 

As for the failed bulb business, wtf. That sounds like usual programmer doing a bodge job issue. Lazy barstewards...

[Nick Jones]

I think the bulb was genuinely intermittent. It’s possible the pressure switch code is a legacy of the previous issues with one failed brake circuit as there is a switch in each circuit and for sure they would have been seeing different values while that was going on….. though no ABS or traction control warning lights then, so the recent traction control light is just plain odd. My ex-LR colleague has a story about a Disco 3 that had a proven and repeatable complete systems meltdown caused by an intermittent brake light bulb.  Took them weeks to find it - eventually found by chance!

I dunno…. And, if it continues to behave, I don’t care either!

[Escadrille Ecosse]

24 minutes ago, Nick Jones said:

I dunno…. And, if it continues to behave, I don’t care either!

[Nick Jones]

Mot day today. I pooped up the hole in the rear exhaust box again as although I do now have a replacement it looks like a huge faff to replace! Also checked it over and found nothing too scary. Unfortunately I missed the small piece of rear coil that had fallen off and the MoT man didn’t….. 

So that resulted in a bit a scramble for parts and a quick fix in the cold drizzle. At least it’s among the easiest jobs on the car (a very short list!).

[Hamish]

At least it’s a fairly easy fix

get it mot’d again in June at least that way if there is anything that needs doing annually it should be in better weather. !!😇

[Escadrille Ecosse]

17 minutes ago, Hamish said:

get it mot’d again in June at least that way if there is anything that needs doing annually it should be in better weather. !!😇

This is a pretty crap time of year to get an MOT

[Nick Jones]

57 minutes ago, Escadrille Ecosse said:

This is a pretty crap time of year to get an MOT

It really is!

2C and raining….. AGAIN!

[Nick Jones]

Indicators that light up but don’t actually flash (although the hazard lights work just fine)…… Ah yes, they all do that sir!  

Under-spec’d relay sticks closed. It’s built into the hazard flasher switch along with the hazard relay. Someone being too clever again…… New genuine are not cheap. Used ones…. wilI’ll fail in the same way. Apparently there are “field repairs” that can be done……

[Escadrille Ecosse]

Neighbours were away daahn sarf in their Audi A3. Got back very late/very early this morning. The car threw its toys out of the pram on the M6 south of Carlisle. Once recovered off the hard shoulder to a lorry park the AA man diagnosed an injector module fault. Common problem says he, so common that he carried a genuine spare in his van.

So £700 lighter (and some eight hours after the breakdown) they were back in Weegie.

But says something the man had one in his toolbox. Aren't modern cars splendid

[Nick Jones]

Ouch…. That’s a big financial hit. How old is the car?

[Escadrille Ecosse]

23 minutes ago, Nick Jones said:

Ouch…. That’s a big financial hit. How old is the car?

About 9-10 years. But not a huge mileage (came down from Shetland).

[Nick Jones]

On 4/8/2025 at 9:25 PM, Escadrille Ecosse said:

Aren't modern cars splendid

Hum….. apparently not when it comes to reliability and cost of ownership. @Gt64fun and I were having this discussion yesterday regarding a failed thermostat on their VAG daily driver. Now integrated into a plastic housing with the water pump and a sensor, thus giving three opportunities for failure in one unreasonably priced and difficult to access part. I’m sure the designers are absolutely delighted with themselves 

[Nick Jones]

So….. thanks to the cleverness and generosity of others on forums and YouTube…… and some local dexterity, the TT has indicators again. I had to buy some keys to get the stereo out, but otherwise a no parts repair at this point.

Keys came from eBay and are really decent knock-offs of the genuine ones at less than 1/10th the price.

Thanks to them the stereo came out easily and YouTube revealed how to the extract the switch. It’s easy when you know how but you’d really struggle to work it out on your own.

The TT owners forum provided the how-to to get the switch itself to bits

This reveals the two relays. The big one on the left is the hazard one. It’s fine. The slimmer one on the right is not and the known failure point. It’s an Omron product and it (or similar) can be bought new and fitted. However, as there are two versions of the switch with entirely different relays (both failure-prone), I hadn’t bought a new one. One version has an open frame and the contacts are easy to free up and clean. Obviously mine is the other one. The sealed one…… so it was unsoldered from the board and introduced to Stanley. Stanley doesn’t agree with sealed….….. oh, look….   Not sealed any more!

Now these contacts can be gently prised apart, cleaned up and tested. Works just fine. Solder back into the board, take it out to the car and test. Yep. Works fine. 
 

Now I have to reassemble the switch, which is a real head-scratcher as reassembly is definitely NOT the reverse of disassembly! Forum to the rescue again (though only in general terms…. More disassembly needed …. Details are must be figured out for yourself……)

Some cussing later and it’s back together, only lightly scarred, and it even still works. Back in the car and the final challenge is that the stereo wants its security code…. Which we do actually have, so victory is secured. Favourite husband status regained!

Obviously it remains to be seen how long this field repair will hold for. Probably I should order a new relay to guarantee the original never fails again!