[NudeLobster]

Hey guys, went to check my oil level yesterday and my oil level is reading "INACTIVE". Oil temp also seems to reach operating temperature faster than normal given the cold weather out and my water pump is running a little longer than normal after shut down.

Is this all caused by an oil temp sensor that has gone bad? I know oil level is based off the rate of change of oil temp and I'm pretty sure water pump runs after shut off based off oil temp. Is this all correct?

Hoping I don't have to replace the sensor... I just did an oil change 1000 miles ago. 80 bucks in oil and filter down the drain if I have to drain it for then senor

Cheers and merry christmas!
Justin

[Th3xf4ctor]

Possible sensor maybe

[thomas88162]

I have seen this for malfunctioning TPMS sensors.

[Efthreeoh]

It is a failed oil level/oil quality sensor. Scan the car with a BMW scan tool and you'll find a fault code. You don't have to lose the oil or filter. Just drain the oil into a clean drain pan. When I replaced my sensor, I just bought a new oil drain container for $8 that had a big yellow screw-on top. I cleaned the underside of the engine belly pan, wiped everything down, and drained the oil into the new drain pan and capped it while I did the sensor swap. I re-poured the oil into the engine through cheese cloth just for good measure.

[3s4u2]

Efthreeoh, Did you just replace your OQS because of a failure or are you still trying to work out the coding issue with the oil counter?

Oh, Merry Christmas and I hope the knee is getting better.

[Efthreeoh]

Merry Christmas! The knee is getting better, thanks for asking.

I replaced the sensor because the CBS wouldn't reset; the sensor was reading the oil level fine (I don't think it is now, though). Once I replaced the sensor and nothing changed, I took the car to a BMW dealer for diagnosis, and that's when I (and the dealer) discovered that the software is programmed to stop taking in the oil quality data and thus deactivating the OCI calculation. We also discovered that BMW's software fix didn't solve the problem of telling you the car is past due on the oil change. I gave up on solving the issue with our friends at BMW.

How's is your car running? What mileage are you at now? You'll probably go past me at some point towards 300K since I just bought a sweet 2008 E86 to take a few days a week of commuting off the E90. I said I wasn't going to get another BMW after the E90, but, well, when an E86 comes up with just 23,000 miles on the clock, what's a guy to do? LOL. I did consider a new 228i, but didn't want to buy a new BMW from the company - trying to keep my boycott intact...

Just to be clear with the OP. The owners manual states that if the oil level system reads "INACTIVE" it means there is a problem with the senor/system and to get it diagnosed at a BMW dealer.

[DANE53331]

Check for chewed wiring from rats just behind the oil level sensor.

[sy2767]

i had the same issue last winter, it turned out it was caused by condensation in my oil from frequent short trips. The sensor would not read the oil level causing the "inactive" prompt. After a few trips that allowed my oil to reach full temp for an extended period of time the moisture evaporated and everything returned to normal.

[Roombata]

I replaced the sensor because the CBS wouldn't reset; the sensor was reading the oil level fine (I don't think it is now, though). Once I replaced the sensor and nothing changed, I took the car to a BMW dealer for diagnosis, and that's when I (and the dealer) discovered that the software is programmed to stop taking in the oil quality data and thus deactivating the OCI calculation. We also discovered that BMW's software fix didn't solve the problem of telling you the car is past due on the oil change. I gave up on solving the issue with our friends at BMW.

Just to be clear with the OP. The owners manual states that if the oil level system reads "INACTIVE" it means there is a problem with the senor/system and to get it diagnosed at a BMW dealer.

I had two (red and yellow) wires broken on the sensor itself. It did not look it was chewed up by critters. I managed to pull the cable out and up so I can splice/solder in engine bay. I could not get the pins out so it made it a little trickier. Managed though. The car would not acknowledge/recognize that the oil sensor started working on its own. My Schwaben NT510 reader with BMW add on could not reset it. The AutoZone tool, despite the fact that it could not read faults, managed to clear once you perform clear all errors. Go figure. Now it works. I Guess, BMW wants you to go to the dealership. The onboard resetting in dash did not allow to reset the oil life until I managed to somehow clear the hidden sensor problem. It's beyond me why the car would not report sensor error, cannot measure - but rather say System Inactive.

[maxxxxxxxam]

Bonjour Roombata,

Peux-tu me donner le lien de téléchargement de l'application Autozone que tu as utilisé pour régler ton problème de niveau d'huile Inactive?

Je te remercie d'avance.
Max

[NZE90]

Originally Posted by maxxxxxxxam

Bonjour Roombata,

Peux-tu me donner le lien de téléchargement de l'application Autozone que tu as utilisé pour régler ton problème de niveau d'huile Inactive?

Je te remercie d'avance.
Max

Qué carajo?

[OMEGA412]

I know this is an old post but for anyone having this issue here's the solution. BMW uses a BSD bus to control and communicate with 3-4 things in the car. The water pump, alternator, oil level sensor, and if your car has one the intelligent battery sensor.(small wire coming off the negative terminal of your battery). Because of the way BSD works if one of these systems experiences a fault all four go down with it. Example, a failing water pump can give you an "inactive" oil level. The way to diagnose this problem is to disconnect your alternator, IBS, and water pump. If your oil level can be read then one of the components you disconnected is faulty. Reconnect components one by one until oil level is inactive again and whichever one causes the inactive oil level is the one that needs replaced. If oil level is still inactive when it is the only thing connected replace oil level sensor. However before replacing any components you should check the continuity along the BSD wire which is purple. I had this issue caused by a loose wire in the water pump connector.

[roman.tsr]

Thank you, OMEGA412, for the detailed description.
I just wonder, if the car detects so significant failure like oil level or water pump, why no any BIG RED warning lights is lightning? If I wouldn't go to the oil level menu by myself I would never know about the problem...

[OMEGA412]

Originally Posted by roman.tsr

Thank you, OMEGA412, for the detailed description.
I just wonder, if the car detects so significant failure like oil level or water pump, why no any BIG RED warning lights is lightning? If I wouldn't go to the oil level menu by myself I would never know about the problem...

Thats a great question for the bmw enginers, it will show a code if scanned but no service or check engine light.

[GLuED]

I had the same issue. I went and ordered a new sensor but didn't have time to change it. When i finally found time and jacked up the car, it turned out the wire to the sensor was chewed on by some rats. I spliced the wire together and everything worked since. What sucked was that my return window for the new sensor expired.

[lowrydr310]

Originally Posted by roman.tsr

Thank you, OMEGA412, for the detailed description.
I just wonder, if the car detects so significant failure like oil level or water pump, why no any BIG RED warning lights is lightning? If I wouldn't go to the oil level menu by myself I would never know about the problem...

There's no BIG RED warning because in those cases where water pump communications or oil level sensor communications are faulty, the oil pressure is still good (plenty of oil) and the engine isn't overheating (water pump is still functional.) Those are smart fail-safes , getting you home with just the warning instead of leaving you stranded.