service engine on - but no codes?
 

Hi,

My wife drove my 2005 4.4l X5 yesterday and came back telling me the "Service Engine Soon" light was on. I went out to the garage and hooked up my OBDII code reader (a mid-range Actron) and it reported there were no codes. It is communicating with the vehicle, it reads, but it reports there are no codes. I then performed the emissions readiness test, it passed no problem, in fact it reports the "MIL" status to be off. Real-time data also reports that the warning is "off."

I then had it scanned with INPA; it found some errors, but they appeared to be random/minor issues (seat adjustment, mirror adjustment, etc). I went ahead and used it to "clear error memory" and re-ran the test; it came back with no errors found. However, the "Service Engine Soon" light is STILL illuminated.

I did fill the car up with gas right after work, so I checked the gas cap, it was on properly though. A bit of a coincidence that it should come on right afterwards I suppose, but if there were an issue wouldn't an error code be logged anyway?

In short, I am a bit puzzled how the light can be on, yet I haven't found any codes yet.

Anyone have any suggestions?

TIA!

hook up the normal obd2 scanner and check for codes / clear the check engine light and see what happens.

Hello, sorry I left that out; but I did try clearing and re-reading with the Actron. SES still on, no errors found...it is strange!

How old is your battery and what kind of voltage range are you seeing sitting / running?

I do not know this information; I bought it last summer, so I am not sure of battery age. I will check voltages later and see - thanks.

OK, so 11.9v not running, 14v while running.

However, after hooking up the code scanner again, I noticed that out of 112 PIDs, only 4 are showing up. This seems very bad to me...

Looking at live data for example, you would normally see all sensor readings, but I have only MIL status, engine speed, vehicle speed, volts, and OBD2 State. Further, if I read all the codes, and then check the categories, all others are showing up as "n/a."

I believe this is why it isn't showing any DTCs; as none of them are available. The scanner is communicating, but only very limited information is being passed.

Is it in some sort of fault mode or something? The dash reports everything is "OK" as well; no indication that it is in some fault or fail-safe.

Thanks.

That is very strange....

- pls call your local dealer to search for recalls or recommended firmware updates, please do so
- if there is one, you have to decide what route to take Indy, dealership or you have the means

Have you use this scanner before on the X? I would get another scanner to verify that it's not the scanner fault.

I'd check the actual age of the battery. These cars are very sensitive to bad batteries.

Screw the stealership unless your under warranty...

I would suggest trying a different code reader, if you see the same results on the 2nd ( known working ) reader and you are sure your voltages look good then I would suggest a good olf fashon reboot of the system! pull the power, let it sit for a good 10-15 minutes with the door open! and then re-connect the battery back up and turn your key to the run position for a good 2 minutes and then start it up.

You'll have to re-calibrate the steering sensor by turning the wheel lock-to-lock and have to hold in your tire button.

then scan it again again :)