Engine Management Light

[waue1978]

Had my engine management light come on Thursday due to unplugging the common rail sensor, but when I plugged it all back in again the light stayed on. Have had a look & there seem to be various versions on this, but does anybody know from experience if this needs resetting or if it should clear on it's own, & if it does, when does it clear.

Prior to Thursday it never came on & there were no problems with the engine - only reason the sensor got unplugged was to find out if it was the common rail sensor for a tuning box.

[steve_earwig]

No idea but you could try disconnecting the battery for a couple of hours. Failing that I'm afraid you'll need to find someone with a box of tricks that can clear fault codes. You might want to leave this until you finish meddling...

[FlySpeck]

where you at mate?

[waue1978]

Andover in Hampshire.

[StevieboyTD]

... a tuning box.

Found your problem ;)

[waue1978]

Tuning box didn't get plugged in yet - just unplugged to check whether I was looking at the right plug or not as I hadn't figured out where I was going to secure the box. Battery disconnection didn't work unfortunately. I take it from the lack of responses that nobody knows for sure whether it resets itself or needs to be reset by a computer?

[FlySpeck]

Hi mate, a rail pressure sensor fault will cause the ecu to shut down to limp mode or just throw a CEL if the condition has gone (as yours has) but will retain the memory of the fault as its in the critical sensor group.

You will need the code cleared but it can be done using any OBD scanner that can talk KWP2000 protocol. Codes can only be reset with the ignition on, not in economy mode, and not running.

When you connect a scanner thats non oem pug, go straight to connect & read codes, write them down, then go straight to "erase codes" - if you try anything else, the ecu will disconnect the comms and you will have to switch the ignition fully off and on again, removing the key inbetween, to get a new connection.

[waue1978]

Nice one, thanks for that. I'll pop & see the guy round the corner & chuck him a drink to clear it.