Whilst fiddling with some wires under the steering wheel (trying fix shift light) I noticed white plug thing that was unplugged - strange I thought so I plugged it back together and then the Check Engine lit up... (unplugged it again)

Is this something to do with changing the exhaust parts and then the ECU gets to know about it via a sensor somewhere and it brings on the Check Engine Light???

 

I believe it is to do with the diagnostics. It is mean't to be left apart. If you join them whilst the ignition is on, the engine check light will flash in morse code which inturn indicates any faults. I'm sure someone on here will know the exact answer.

Hope this helps.
G.

 

Gareth60 - Covered most of it. If you get the engine check light come on whilst under normal driving, this indicates a sensor failure etc. Plug in those two blocks, count the flashes, 1 set of slow and 1 set of fast. Put these two numbers together, contact your nearest Subaru dealer and they will order the part.

simb