Do fault codes automatically clear after fixing?

[Kambo]

I know you can erase them manually but just wondered if you get one pop up and fix the problem and it still shows once started up should it clear after some time? Or is it meant to stay until manually erased?

Had a yellow light - Engine Coolant Temp sensor come up, changed it, started it up and engine light still there, hooked up scanner and obviously the same code, went for a good drive, parked up and when I got back and started it up again the light went out, hasn't come back since and this was a couple of days ago

Normal?

 

[traumapat]

Ive always cleared things down manually but assume as the problem is no longer occuring the lights gone out. If you cant erase the codes you could try disconnecting the battery for 30mins. This might reset some of the parameters that adapted to the faulty sensor.

Is your temp gauge now hitting 90 and staying there?

 

[Guizado]

Some do some wont I guess, I was once messing with my steering wheel, and putting some contact cleaner, that made the airbag light come on, only cleared after clearing the code.
Dont know about any others tho.

 

[Kambo]

Ive always cleared things down manually but assume as the problem is no longer occuring the lights gone out. If you cant erase the codes you could try disconnecting the battery for 30mins. This might reset some of the parameters that adapted to the faulty sensor.

Is your temp gauge now hitting 90 and staying there?

Mine has never been past 90

Didn't know about the battery reset to clear any previous faulty sensors. Thanks for that

I kept the engine light on after I had scanned it again as I presumed it was just showing me the same fault code, after I had parked it up and started it up the engine light went out, so from this I'm again presuming the engine had 'found out' the problem had been fixed?

I know some codes like the software one come up if you disconnect the battery but I wasn't sure if error codes were meant to be manually erased or done when the ecu recognises the fault has been rectified?

 

[traumapat]

I think it depends on the fault as mentioned above. More serious faults might need to be erased.

Try a battery reset and if its worked you should only get the battery code on a re scan.

reason I mentioned the gauge is that often a coolant fault can turn out to be the thermostat stuck preventing the coolant from hitting the correct temp. You usually find the temp will drop back from 90 when driving if thats the case so if thats happening it could be why the codes reappeared.

 

[cupra-barn]

IIRC something like a resistance fault like an abs sensor will clear automatically but a fault logged such as a coil pack for instance would need to be cleared.

The best bet is to clear it anyway and then you know for sure

 

[andycupra]

depends on the fault code.
some clear straight away, some after so many cycles while others needs to be cleared.

 

[sheldon]

i always find it easier just to quickly plug in the ELM ODB2 Bluetooth and clear codes with app on phone takes only a few seconds.

 

[Kambo]

Just replaced the ECT switch, rad thermo switch and new thermostat, it was bringing up the ECT one again but this is the one that automatically went off after a drive

I've got a cheapo scanner from ebay for £15



Can't fault it really, reads and scans and deletes fine, I did the battery reset and just the software one came up only (18263) so deleted that, had none since

So some have to be erased and some are done automatically, cool, cheers for the info

 

[LEE69]

On the other side of the coin you can have a code stored and the light NOT come on, i have before,MY liquid gauge doesn't pick it up but vag com does, weird.