Engine Management Light Always On.

[PW39]

My engine management light has been constantly on for several years now without any problems, but with the MOT coming up soon it will not pass as it is.

I need to get it working properly or maybe not have it on at all, just to get it through the MOT.

I have taken out various fuses and disconnected the Battery but all to no avail.

1999 1.6 Auto 5 door hatch.

Any ideas please?

Pete

[Druid Boy]

According to the AA you are ok.

http://www.theaa.com/motoring_advice/car-servicing-repair/mot-changes-2012.html

The VOSA site was less helpful.

Maybe call your MOT guy and ask him.

[PW39]

Thanks, I'll pop round to the MOT station.

[fractureman]

Only lights to fail mot are airbag/srs lights & abs. Engine management lights are ok to pass mot as far as I know

[PW39]

Thanks chaps.

[Devon Aygo]

At present an Engine management is only an advisory item and not a failure, VOSA are currently consulting and awaiting some legal amendments once these are sorted the light being on or even missing will become a failure come your next Mot

[Konrad C]

Due to the way the EML works on different cars, I would rather the EML be an advisory and fail if the car doesn't meet the emissions standard. Some cars have a fall back setting which still meets the emissions.

As said earlier and in the forum, some owners have passed the MOT emissions.

Remember the EML may light because something is out of set parameters, without actually affecting the running of the car.

That means if the EML is signalling a fault, the owner will have to get it fixed as soon as possible and not ignore it.

I last had the EML on a few weeks ago, when the Lean-burn (O2) sensor cable was damaged by the air-con fan. It was fixed immediately.

The problem is that some owners ignore any warning lights which could be serious, so VOSA are looking at that angle.

[PW39]

I feel comfortable that, although the light is on it can be ignored, it has been like that for several years now.

For a car that was built in 1999, it is incredible and runs faultlessly.

[Konrad C]

If I am correct, the most likely problem is the heated circuit in the lean-burn (o2) sensor has failed. The sensor still functions and the car runs as normal.

Your car like mine has self diagnostics, so you can find the code without any additional code readers.

This is done by locating the OBD socket/fuse box, which is located behind the storage box, by the drivers right leg. The OBD socket is above the fuses.

Looking at the socket, get a paperclip and join the 4th pinout on the upper row, and the 5th (13th) pinout on the lower row.

Turn the ignition on but do not start the engine!

You will then notice The EML, ABS and SRS lights flashing. They should have a constant flash, but since your EML is on, it should blink twice, a short space, then blink once. There is a longer space before it repeats the sequence or, if there are any other faults blink a different two number code. Code 21 is the lean-burn sensor.

The EML codes only works for the pre-vvti engines. vvti engines will need a code reader. The ABS and SRS codes works with all cars, unless Toyota have changed that in recent times.

If you do the above check, at least you will be prepared if VOSA do choose to make the EML a main test item.

[PW39]

Interesting.

So two blinks is code for 2 and one blink is code for 1 indicating code 21, thus verifying that it IS the lean-burn sensor, have I got this right?

I'll have to get my son to do this sometime soon as I am unable to get down and bend that low anymore.

[Konrad C]

Interesting.

So two blinks is code for 2 and one blink is code for 1 indicating code 21, thus verifying that it IS the lean-burn sensor, have I got this right?

I'll have to get my son to do this sometime soon as I am unable to get down and bend that low anymore.

Yes this is correct. The best thing is it's free. Also not many code readers are compatible with the pre-vvti Avensis.

[jmac200t]

Hi,

what pin outs can you use to clear a fault code.

Regards

jmac200t

[Konrad C]

To clear any faults stored, go to the fuse box in the engine bay, and pull the 15A fuse marked EFI. Wait about 30 seconds to a minute, then replace.

The car will then need to be driven at various loads and engine speeds for a few miles, so the ECU to relearn parameters.

[PW39]

Hello again

Unfortunately pulling the fuse out didn't clear the fault.

However your advice to find the fault code worked a treat, yes it was code 21, the lean burn sensor.

As the sensor isn't working could I just pull it's connection block apart, I imagine that would turn the EML light off but would
it affect anything else?

[Stephen Andrews]

Hi can you help me i have a Avensis verso 04 last year we went on holiday & i got the aircon re gassed but after 2 weeks when i got this done the management light came on!! so i disconnected the Battery lead put it back & light was out!! however a week later it came back on!! stayed on for a 2 3 weeks then off & there was no power loss or fuel trouble & a year to the day it has came back on!! now i was using my aircon cause its hot in july But im thinking is it something to do with the air con!!!?

[Konrad C]

Hi Stephen. Check the routing of the cabling to make sure no wire is near the fans. My O2 cable was caught by the air-con fan. which I repaired.

Your car is totally different so there may be another reason. You should get a diagnostic check done. Either buy a code reader or find a garage or friend to do it for you.

You need to start a new post because I think your issue is more specific to your type of engine.

Konrad