Emission control warning light - causes?

[BrendanM]

The emission control light came on this morning and has stayed on. I've driven the car, left it parked up for 1 hour, started the engine again and the light is still on. Any ideas?

The user manual suggests that the light staying on constantly is less urgent than if it flashes. If it flashes, the advice is to drive at a reduced speed and take to a dealer. If it stays on, the advice is simply to take to a dealer as soon as possible (doesn't say immediately).

The car is a 2007 A6 3.0 TDI. I'm certain it doesn't have a DPF.

I'm due to start a 250 mile journey this evening. I don't have VCDS so can't run a diagnostic. Does anyone have any ideas why this light has come on, and how risky it might be to ignore it this evening and do the journey?

 

[KrisKrk]

This is Engine Management Light (EML) and can be related to many issues.

Unfortunately, only solution to find out what is the problem, is to run diagnostics with vcds. Assumption in cases like that can be bad.

Anything unusual happened in the last few days? Car has been driven in a odd manner (excess speed), you've hit something, has shown any other odd symptoms or anything else happened with the EML?

 

[BrendanM]

This is Engine Management Light (EML) and can be related to many issues.

Unfortunately, only solution to find out what is the problem, is to run diagnostics with vcds. Assumption in cases like that can be bad.

Anything unusual happened in the last few days? Car has been driven in a odd manner (excess speed), you've hit something, has shown any other odd symptoms or anything else happened with the EML?

Cheers for this, but it's not the Engine Management light. My user manual says it's the Emission Control System. See below picture for symbols for EML on the C6 A6 and the explanation in the user manual.

To answer your question, no, nothing unusual in my driving habits or environmental factors in the past few days.

 

[Retroman]

You really need to get an idea of the fault in order to take a view on continued driving. VCDS is ideal but not essential - many code readers can give you an indication of what is wrong. As the car has not initiated "limp mode" it could well be minor like a lambda sensor or electronic EGR valve reacting slightly out of tolerance - who knows.

 

[BrendanM]

You really need to get an idea of the fault in order to take a view on continued driving. VCDS is ideal but not essential - many code readers can give you an indication of what is wrong. As the car has not initiated "limp mode" it could well be minor like a lambda sensor or electronic EGR valve reacting slightly out of tolerance - who knows.

Good advice mate. Thank you. I've parked it up for the weekend and I'm now doing the 460 mile round trip in a Vauxhall! Talk about a bad day getting worse!

 

[Seanchadwick2k3]

Carista dongle from amazon, about £15 gets you a one month free trial of the app. @KrisKrk has one also. I used mine for the first time the other day an cant fault it. Told me which of my parking sensors was knackered and let me enable needle sweep. Cheaper than vcds but doesnt have the same functionality.

 

[BrendanM]

Carista dongle from amazon, about £15 gets you a one month free trial of the app. @KrisKrk has one also. I used mine for the first time the other day an cant fault it. Told me which of my parking sensors was knackered and let me enable needle sweep. Cheaper than vcds but doesnt have the same functionality.

I ordered one of those this morning. I might be in touch if I run into any difficulty using it.

Interestingly the light went out this morning!

 

[KrisKrk]

Carista is simple in use. Plug it in into OBD2 port, download Carista app, turn bluetooth on run the app. It will ask you which dongle you use and allow you to continue with scan.
Results with eventual error codes allow you to google particular error code.