B.B. went for its annual MOT yesterday.
The previous 9 have all been passed with no advisories.
However yesterday whilst it was being tested the E.M.L. came on for a moment, giving an instant fail.
The tester cleared it and said the only fault showing was the ever present PO40D-00 (2F), so he started the test again and it sailed through with no advisories.
I have never seen any engine management lights but would like to understand what caused it to glow yesterday.

Any thoughts as to where I should be looking??


Mike.

Click image to enlarge

Anything showing on a GAP IID scan inc when pending faults are enabled? 2012 TDV8 Vogue (L322)

Only PO40D-00(2F) which has been showing for many years.
Mike. G reg 2.5VM Vogue Portofino red 1991- 1999
V reg 2.5td P38 Rioja red 1999- 2006
53 reg td6 Vogue Oslo blue 2006- 2015
11 reg 4.4 TdV8 Vogue SE. Baltic blue 2015- date.
https://www.fullfatrr.com/forum/topic56162...tty+affair

Maybe the ignition was on for a long time when they were testing it and the battery dropped in voltage. Never seen this cause an EML but low battery voltage is a known cause of all sorts of spurious faults and warnings.
it passed - my MOT test is tomorrow 2012 TDV8 Vogue (L322)

Presumably the tester didn't record the code before clearing it.

I am not sure if he actually “manually “ cleared it or if it just cleared itself, but he just said that it came on for an instant and he couldn’t see any cause or reason.
My engineering brain doesn’t like mysterious unexplained things so I am keen to try and solve it.
Mike. G reg 2.5VM Vogue Portofino red 1991- 1999
V reg 2.5td P38 Rioja red 1999- 2006
53 reg td6 Vogue Oslo blue 2006- 2015
11 reg 4.4 TdV8 Vogue SE. Baltic blue 2015- date.
https://www.fullfatrr.com/forum/topic56162...tty+affair

If it came up then cleared most likely misfire detected for a time.

Once switched off and restarted code has gone

EGR sensor code which could even be a bit of dirt on the sensor whhich has then been dislodged? John
2008 Stornoway Grey 3.6 Tdv8 Vogue
2005 TD6 Java Black Vogue - Written off!!
GAP iiD BT
2003 Discovery TD5 Auto, Nanocom Evolution - gone to a new home!
MasseyFerguson 152 - No electronics!! - Sold

Thanks for all your help, I will see how it goes , at least he didn’t hesitate to do a full retest .
Cheers
Mike. G reg 2.5VM Vogue Portofino red 1991- 1999
V reg 2.5td P38 Rioja red 1999- 2006
53 reg td6 Vogue Oslo blue 2006- 2015
11 reg 4.4 TdV8 Vogue SE. Baltic blue 2015- date.
https://www.fullfatrr.com/forum/topic56162...tty+affair

If the tester turned the engine off (not running but ig on to enable steering to be turned )whilst it was being tested and then put front end up in air and did lock to lock whilst looking at various suspension joints it will bring on EML when restarted as it throws steering angle sensor out of calibration , restart and lock to lock a couple of times and it'll sort itself out , also happens on D4's and prob RRS, make sure tester keeps engine running whilst moving steering on test (found this out a few years ago when it happened to me when having one of my customers cars tested )

Matthew’s,
Thanks for your very detailed reply. I can understand that could easily be the explanation.
The problem I have is that it is such a busy 2 man specialist LR independent garage that I don’t like to delay them by talking through the problem with them ,,
I can say though that I have done 300 miles this week, both long and short journeys with absolutely no problems, so I will just accept it was a one off event , but pity about the blot on my otherwise blemish free MOT history.
Cheers
Mike. G reg 2.5VM Vogue Portofino red 1991- 1999
V reg 2.5td P38 Rioja red 1999- 2006
53 reg td6 Vogue Oslo blue 2006- 2015
11 reg 4.4 TdV8 Vogue SE. Baltic blue 2015- date.
https://www.fullfatrr.com/forum/topic56162...tty+affair

Easy way to show this is to do just that , jack front end up , ignition on and lock to lock it a couple of times by pushing on wheels (as would happen in test ) , , pop it back on floor and start it up , eml will be on and fault code will be steering angle sensor , lock to lock it with engine running a couple of times and it will clear after recalibrating , can't believe your tester failed it on this and then passed it after clearing fault but each tester has there own foibles .You would not believe the argument I had on Friday with a temp tester and a Defender ABS light , would not accept that self test function and light going out requires vehicle moving at 5kmh.