Code 00771:

Lower adaption limit (additive) not re 00771

Fuel level sensor (G)

 

Actually that's the only codes, I thought there were more, thankfully not.

 

Do you think there is an issue with the ECU, as I'm guessing that would regulate the fuel, emissions & general running, ie restricting the power/acceleration?

 

If so would it be better to just look for a new or good second hand one?

 

Thanks

I forgot to add, that I checked the throttle position sensor & all was ok. I also tested the accelerator & that was all ok.

I've just looked at the 00771 code & that seems to relate to a faulty fuel gauge, but the car shows the fuel level ok. The only dashboard issue is the rev counter has gone over past 7000rpm, but does jump back (occasionally), but I checked the dashboard for codes & nothing showed as faulty. I have read that it can be something to do with a connection on the alternator, though not certain about that.

Engine ECUs are usually very reliable, but for some reason this one seems not to be telling the diagnostic system what faults it is aware of. None of the fault codes you've listed are from the engine ECU, they are all from other modules.

Yet the 01314 code says to me that there are codes in the engine ECU which are likely to be key to solving this.

I will look at wiring info for you when I get a chance, to see if anything suggests itself about how to proceed.  I would always tend to blame wiring problems ahead of electronics failures, though of course the latter can happen.

 

 

I've just had a chance to go back out to the car & try the OBD2 & this is what it showed, but I don't think it will help much, other than showing that it's not picking up any codes. 

It would be good to get a VCDS on it and see which modules that can/can't see. VCDS Lite will suffice, I think. Shame you're not a whole lot closer.

 

I'm guessing that the engine ECU is one of the the four "monitor not completed" items.  

I don't know anyone with VCD's but I'll see if I can get hold of it online.

 

Thanks again for your help, it really is appreciated.👍

I could be wrong, but I'm fairly sure on the DSG you move the stick left for manual, and on the older box, you move it right. so I'm virtually sure that's a torque convertor/tiptronic box. 

 

I've had a read round, and that first code, like you say, points to the level sender. I'm wonderring if there's an issue in there that's else affecting the lift pump, but that's me taking a stab. 

2 hours ago, Yeti said:

I could be wrong, but I'm fairly sure on the DSG you move the stick left for manual, and on the older box, you move it right. so I'm virtually sure that's a torque convertor/tiptronic box. 

 

I've had a read round, and that first code, like you say, points to the level sender. I'm wondering if there's an issue in there that's else affecting the lift pump, but that's me taking a stab. 

The fuel gauge itself shows the levels ok, & when I checked the injectors the fuel re filled straight away. Also the car idles ok, ticking over between about 690rpm - 720rpm & revs/accelerates ok while standing. So I don't know if that helps, though I'm guessing it could cause some issue.

 

I've ordered a cable to connect to an older laptop which I still have, so I just need to get a copy of the VAG COM VCDS software & fingers crossed I might get to the bottom of what codes are hiding.

 

I'm just wondering if someone might have messed with the ECU in the past to cheat something?🤔

 

But thank you for your input, it is much appreciated.

 

 

VCDS Lite is freeware, downloadable here https://www.ross-tech.com/vcds-lite/download/index.php

Download button at bottom of page. I think you can safely ignore the "2005 and earlier" statement. 

 

Unless you register it I don't think you can do Autoscan of all modules with one click, but you'll still be able to scan any and every module individually.

Edited 16 March, 20233 yr by Pete1

19 minutes ago, Pete1 said:

VCDS Lite is freeware, downloadable here https://www.ross-tech.com/vcds-lite/download/index.php

Download button at bottom of page. I think you can safely ignore the "2005 and earlier" statement. 

 

Unless you register it I don't think you can do Autoscan of all modules with one click, but you'll still be able to scan any and every module individually.

Thanks for the link.👍

 

I'll register & download that now, so fingers crossed I've ordered the correct cable & that it works on a windows 10 laptop.

You don't need to register to download it.

Registering (99USD) it unlocks extra features and enables support on their forum.

Neither will be needed initially, and you should verify that you can get it working with your laptop/cable/car combination before spending any bucks on registration. 

Which cable have you bought?

 

I never thought of it that way, so thank you for saving me from possibly wasting more money.👍

Sorry for the delay in getting back to you, but the cable arrived later than expected, but I got it this afternoon & gave it a try & here are the results I got back, which I hope help.

 

The first 3 were faults that came up under Auto Scan, & the bottom 2 were 1 which I did for the Instruments & the second one was just the engine.

 

VCDS-Lite Version: Release 1.2
Tuesday, 21 March 2023, 15:40:20.

Chassis Type: 9N - VW Polo
Scan: 01,02,03,08,09,15,17,19,25,37,44,45,46,56,76
 
-------------------------------------------------------------------------------
Address 01: Engine       Labels: Redir Fail!
   Controller: 03C 906 024 AP
   Component:  MARELLI 4HV        2220
   Coding: 0000075
   Shop #: WSC 11111
   VCID: 6CAB47B30F93
1 Fault Found:
18049 -  Please check DTC Memory of A/C Controller
            P1641 - 000 -   -
Readiness: 0110 0101

-------------------------------------------------------------------------------
Address 02: Auto Trans       Labels: None
   Controller: 09G 927 750 HF
   Component: AQ 250 6F           1128
   Coding: 0000072
   Shop #: WSC 00788
   VCID: 7C8B77F37FF3
1 Fault Found:
01314 -  Engine Control Module
            013 -  Check DTC Memory - Intermittent

-------------------------------------------------------------------------------
Address 03: ABS Brakes       Labels: 6Q0-907-37x-ABS.LBL
   Controller: 6Q0 907 379 AF
   Component: ABS 8.0 front   H05 0002
   Coding: 0002289
   Shop #: WSC 00788
   VCID: 817586079811
No fault code found.

------------------------------------------------------------------------------

------------------------------------------------------------------------------

VCDS-Lite Version: Release 1.2
Tuesday, 21 March 2023, 15:50:27.
Control Module Part Number: 6Q0 920 904 EX
  Component and/or Version: KOMBIINSTRUMENT VDO V08
           Software Coding: 01441
            Work Shop Code: WSC 88888
                      VCID: 8C6BA733AF53
1 Fault Found:
00771 -  Fuel Level Sensor (G)
        30-10 -  Open or Short to Plus - Intermittent

-----------------------------------------------------------------------------
VCDS-Lite Version: Release 1.2
Tuesday, 21 March 2023, 15:51:34.
Control Module Part Number: 03C 906 024 AP
  Component and/or Version:  MARELLI 4HV        2220
           Software Coding: 0000075
            Work Shop Code: WSC 11111
                      VCID: 6CAB47B30F93
1 Fault Found:
18049 -  Please check DTC Memory of A/C Controller
        P1641 - 000 -   -
 

So I am hoping that this might make more sense, though I'm guessing that the code for the Auto Trans is the one thats giving the driving problems, but that is just me guessing.

 

But again, your help & advice is gratefully appreciated.

Sadly that doesn't seem to shed any more light on anything as far as I can see.  Almost like each module is saying "hey, don't look at me, it's so and so that's playing silly buggers"

If you scan the HVAC module what does it say? Can't imagine it can be anything relevant, mind.

 

Maybe keep scanning the engine and transmission modules over the next days, hoping to pick up an intermittent fault before it clears itself.

HVAC Module?

 

I'm not the greatest when it comes to knowing this sort of stuff, is that something I can get it to scan separately?

 

I have just remembered something that I wonder, might have caused a fault with the ECM, that is that the rear screen washer pipe has been disconnected (another job for me to fix), but I never knew about the issue until my brother in law said the rear screen would wipe, but gave no water. So I had a look, & I found that where the pipe is disconnected, it still shoots water out, but it's aimed directly at the ECM, so I'm guessing that my brother in law would have been trying to get water sprayed out, but it probably soaked the ECM, & that could be when he started having the driving problems.

 

So I'm guessing that will not have helped the problem & thinking more about it, could it be a cause of the problem?

 

I think I will be looking at fixing that tomorrow.

 

???

Edited 21 March, 20233 yr by 00Dash

1 hour ago, 00Dash said:

HVAC Module?

Sorry, technical name of A/C control module, number 08, should be able to scan separately.

Will probably give a few errors, like recirculation flap motor, G65 pressure low etc.

 

ECU connectors are usually pretty decently environmentally sealed, but well worth a look. Also visually check for any wiring in that area that may have deteriorated or corroded. Tends to be wet even without screenwash showers due to scuttle drainage overflows down wiring loom legs.

 

39 minutes ago, Pete1 said:

Sorry, technical name of A/C control module, number 08, should be able to scan separately.

Will probably give a few errors, like recirculation flap motor, G65 pressure low etc.

 

ECU connectors are usually pretty decently environmentally sealed, but well worth a look. Also visually check for any wiring in that area that may have deteriorated or corroded. Tends to be wet even without screenwash showers due to scuttle drainage overflows down wiring loom legs.

 

Thanks for that, I'll get it looked at tomorrow & let you know what I find.

 Your help is much appreciated 👍

Hi,

 

I'm in the car now & have just done the HVAC scan & here are the faults found:

 

----------------------------------------------------------------------------------------

VCDS-Lite Version: Release 1.2
Wednesday, 22 March 2023, 13:49:21.
Control Module Part Number: 6Q0 820 045 
  Component and/or Version: Klimaanlage        X0850
           Software Coding: 
            Work Shop Code: 
                      VCID: EAA7C1AB8567
2 Faults Found:
65535 -  Internal Control Module Memory Error
        00-00 -   -
00819 - Shareware Version. To Decode all DTCs
        07-00 - Please Register/Activate

 

-----------------------------------------------------------------------------------------

 

I don't know if this sheds any more light on the problem, but i have my fingers crossed.

No light I'm afraid. Low refrigerant pressure as is often the case http://wiki.ross-tech.com/wiki/index.php/00819#:~:text=00819 - High Pressure Sensor (G65)%3A Signal too Low,-Possible Symptoms

 

Does the A/C work at all in terms of cooling?

4 hours ago, Pete1 said:

No light I'm afraid. Low refrigerant pressure as is often the case http://wiki.ross-tech.com/wiki/index.php/00819#:~:text=00819 - High Pressure Sensor (G65)%3A Signal too Low,-Possible Symptoms

 

Does the A/C work at all in terms of cooling?

 

To be honest I think the aircon needs re gassing, but I saw the fault with the pressure sensor, so I'm going to get one & change it, as it's only around £10 - £15, & I had forgotten to order it, so I'll do that tonight & I might be able to pick up locally tomorrow. I know I'll need to get it re gassed, but I will need to get it driving/running properly first, which will hopefully help with the emissions, & that will able me to get the MOT it now needs, as it has just run out.

 

I do have another thing I need to sort & that is to figure out the route the rear washer pipe takes, so I can also get that sorted for the MOT. I had a look today & I cannot see where the pipe should be going from the engine bay, & the only Youtube video I found was someone sorting the connection at the back of the rear passenger seat & hatch door.

 

I did find an interesting video with regard to the HVAC fault code '65535 -  Internal Control Module Memory Error' which I was debating on looking at, but was a bit unsure.🤔

 

 

 

But you asking about the A/C has reminded me to try changing that pressure sensor & I'm hoping that might possibly resolve that issue, though again I'm guessing it will need re gassing before the fault might clear.

I also forgot that I found an older post on a different forum, with a person with a similar, if not the same problem, but they never actually say where or what the fault was, & they've not been online in the group since 2020.....shame or I would have joined just to see if they could tell me how they fixed it.

 

https://forums.ross-tech.com/index.php?threads/18443/

 

 

Don't spend on a pressure sensor, chances are the fault is simply telling you that it needs a regas, not that the sensor is duff.

 

I think the 65535 error is fairly common, I think my Polo shows that. Doesn't seem to affect anything though.

Well I have an update & solution, which I hope makes sense😁.

 

I gave the car to a VW Specialist, who had the car for several weeks, & it had them confused. They used the VW dealer software & the Ross Tech software & they were confused as they didn't get any error codes. So they took the car for a test drive, first without a laptop connected to the car & they said that the car seemed ok, so I suggested they take it out with a laptop connected, which they did & could see that the software said the car was revving around 2000 rpm, but could hear the engine was revving closer to 4000 rpm & they cloud also see that the car wasn't changing gear correctly. So they had a word with a gearbox specialist, who suggested it could be possibly linked to a speed sensor, which the car has 2, 1 inside the gearbox & 1 outside, but they checked out as being ok. So they then checked the engine to see if there were any issues with that, but other than some wire looking a bit bad (which they replaced) they could not find fault with the engine. So they tried changing different sensors around the car, but it still had them banging their heads as none made any difference. I asked if they had checked the faulty instrument cluster, but they had no way of checking this, plus they thought it had corrected itself, as it had reset itself, but this only happened once, then failed again, so since they were stumped I got the car back. But I have to say, for all the work they put in to trying to find the fault, they never charged me for any work, so I made a contribution to the works biscuit fund, which they were happy to accept.

 

So anyway, I took the car home & had a look online to see where I could get the instrument cluster fixed, as I knew it had the problem with the rev counter which had to be fixed & I found a company called Cluster Repairs UK, where I was quoted £99+vat, which included the repair & next day return postage, which I thought was a good price as they would fix it without it needing to be re-coded. So I sent it away & next day I had a message from them to say they'd received the cluster & that it would take between 1 - 5 days, & on the 5th day I received an email to say it was all repaired & that I'd get a call to say what they'd found & the cost with vat & parts was £119.40, a lot cheaper than a new cluster from VW.

 

I received the cluster back  yesterday & fitted it straight in to the car, & I was over the moon to have the car working properly again. As it turned the cluster had not just a rev counter failure, but for some reason, when being diagnosed, they found it was holding power in the dials, during a time just after the ignition was simulated as being turned off, this was not the power that would keep the time showing or the mileage/trip computer showing, it was as if the ignition was still on. So they ended up not just repairing the rev counter but also this strange power issue, which they said would have caused other faults later on, but as they weren't sure if this power problem was linked to the rev counter failure they only charged for one fault, which I was very grateful to them for, as it saved another £99.

 

So there you have it, the problem with the car all came down to faults in the instrument cluster, as apparently it is linked to the cars ECU & it was giving false messages, hence the different codes in the beginning. So the moral of this is......if your instrument cluster looks to be working itself, & your car is not working quite right, then I personally would suggest you go to https://www.clusterrepairsuk.co.uk/ & see about sending your cluster to them to be repaired first.

 

Thank you again to all who were able to offer some help & advice, it was gratefully appreciated.👍