VW Passat 2015, help needed

terryG79

In dire straits here, let me fill you all in. I have a 2015 2.0 TDI Passat and a few weeks ago it started cutting it whilst driving down the road and had a flashing spring in the dash, I dropped it into my local indie and he said it had "open circuit injector one and four" he deleted the codes and the car seemed to drive fine until 3 days ago when I lost full beams, horn, wipers and washer jets they just won't work at all. The car drives fine no cutting out issues now but this is just heartbreaking. I don't want to go main dealer as I know they will just keep fixing different items until they rectify the issue. Does anyone have an idea what it might be. Things I've done ( got all fuses checked both under the bonnet and inside the dash, all fine) (got VW to run a diagnostic and they can't find an issue) (replaced fuel filter, air filter, and added a carbon burner into the tank) could this be a BSI issue or a BCM or something as small as a relay??

Kind regards

Toyotafanboi

They are very fond of injectors, if you were getting an open circuit fault I'd say you haven't heard the last of that. Its unusual for the fault to clear and stay away though, usually if the injector fails with an open circuit fault, there's generally no coming back from that so I'd be dubious as to whether open circuit was definitely the fault he got. If the car was juddering or hesitating with the coil light on the dash, clearing the faults wont fix it, it will be back unfortunately.

Sounds like you have two separate issues tbh. As the other bits you mention arent ran from the same control unit as the engine/ injectors. Possibly an issue with the steering column control unit as all your issues relate to the steering wheel and stalks, horn, wipers, main beams etc. Passats of that era are also prone to failure of those control units.

The most expensive mistake you could make here is getting a cheap diagnosis and having some cowboy charging you for clearing codes and fluting around. I'd brace myself for a bit of a bill here but rather take a bit of a hit and have it done right. I think you have to scan those Passats just to see what model steering column control unit it has as there are a few different kinds fitted.

terryG79

Thank you, I know and I really think I might be heading down the main dealer road, although the car has been driving perfect until the other day when the latest issue arose. This is when I came across a BCM issue thread from a different site and it sounds like the problem. I know the injectors aren't intermittently failing and working and I think that's why I think but I don't know as I'm not a mechanic, it could be a BCM issue. I think that's a new name for the CCM in the b6 Passat's. I have read a faulty or failing BCM will throw up a lot of other error codes like what seems to be happening now. Just to add when the car did stall and I pressed the engine start button it just kept going ggggggggg but when I took my finger off the button and pressed it again it immediately started. This is why I'm pretty sure it's an electrical fault and the BCM is throwing codes like injector circuit open, but it's driving perfect and getting on average 60mpg

terryG79

terryG79 wrote: »

Thank you, I know and I really think I might be heading down the main dealer road, although the car has been driving perfect until the other day when the latest issue arose. This is when I came across a BCM issue thread from a different site and it sounds like the problem. I know the injectors aren't intermittently failing and working and I think that's why I think but I don't know as I'm not a mechanic, it could be a BCM issue. I think that's a new name for the CCM in the b6 Passat's. I have read a faulty or failing BCM will throw up a lot of other error codes like what seems to be happening now. Just to add when the car did stall and I pressed the engine start button it just kept going ggggggggg but when I took my finger off the button and pressed it again it immediately started. This is why I'm pretty sure it's an electrical fault and the BCM is throwing codes like injector circuit open, but it's driving perfect and getting on average 60mpg

Just a little add, everything else on the steering wheel works like the volume off the radio and switching between menus etc, but sometimes I get a warning on the dash that their is a problem with the ACC cruise control, and the odd time I get a key not found when it's on the car and the car won't start.

Toyotafanboi

But if the engine was chugging and hesitating then it wasnt just a spurious fault from a control unit, there was a physical fault for a period of time so something is failing. That and the BCM/ CCM/ J519/ whatever you want to call it doesn't really have any involvement in how the engine runs and doesn't control the injectors. Still think you've two separate issues here, it's guesswork obviously but gut instinct here is two separate faults. Definitely one for a dealer or a specialist anyway IMO, a have a go here will make this much more costly.

terryG79

Thank you, I'm hoping it isn't but if it is it is what it is and I'll have to take it on the chin. Is it not strange that it now drives perfect with no chugging etc and fuel economy is good? Thanks for your help

darragh o meara

It would be worth getting the battery checked, I had a lot of random electrical faults/issues with a Passat a while back and it turned out to be the battery which was starting to fail. The battery voltage was dropping a bit too much when cranking and took too long to get back up to normal which caused under voltage errors on the main control units causing them to shut down.

Took a lot of work to find that. Like you I was getting all manner of faults for injectors etc. and was about to go down the route of replacing the ECU as some had diagnosed as the problem. A new battery and the car was 100% and has been since, new owner who I meet regularly swears it’s one of the best cars he’s owned.

terryG79

Thank you I'll have a look at that, I have a vw data plug in the ECU port in the car which reads certain things like fuel amount and battery voltage and I have noticed sometimes the voltage does be under where would be normal

vectra

I was going to suggest battery as well, They can do lots of weird things when the battery level drops. Have you noticed the stop/start not working with a while?

Toyotafanboi

A weak battery wouldn't cause rough running though?

Edit: if you have a data plug, post the voltage reading with engine running and off and we'll have a better idea.

darragh o meara

terryG79 wrote: »

Thank you I'll have a look at that, I have a vw data plug in the ECU port in the car which reads certain things like fuel amount and battery voltage and I have noticed sometimes the voltage does be under where would be normal

Most garages would have a device to check battery health, I would advise getting someone to test it, its worth checking the altenator output too so you can rule that out.

terryG79

Thanks Darragh I greatly appreciate that. This week I've had more madness happen. The wipers, indicators, horn and full beams all came back and now I have two new errors keyless access system faulty and auto stop start system faulty but they both go off the dash when the car is driven for about 30 mins it's the weirdest thing in the world.