[MX55]

Hi X3Bimmers,

After spending quite a lot of time to find a solution from the forum, I decided to ask your help to solve a strange problem. Here is the problem.

- Because of my trip, I missed the oil change due. So I changed my engine oil with -380 miles service overdue.

- After engine oil change, I tried to reset the service due using the well-known hidden menu procedures. Not working.... I saw "Reset Impossible" message for Engine Oil service.

- Using INPA and Tool32, I tried to reset the service due. Failed... So I erased all fault codes and reset the due date. It worked The due was changed to 12000 miles. Unfortunately, one minute later the due changed to -380 miles

- While i-Drive says All Systems OK, I noticed that there were two error codes: 0x201004 and 0x1C4110.

- I also noticed that engine oil measurement is "INACTIVE" I thought it was due to the service overdue...

Have any member had this problem? Is it due to bad oil level sensor or software issue? I am confused because the i-Drive says all systems are working. However, there are two error codes in DME...

[Barbera335]

Rodent damage to either the oil level sensor or the oil temperature sensor. Oil level sensor is easy to get to. It is mounted to the bottom of the oil pan. Go underneath the car and check the wiring. I am 90% certain the wiring will have been cut by rodents. The next possible location is the oil temperature sensor, unfortunately this one is under the intake manifold and will require removal of the manifold in order to check the wiring. Common issue on many BMW models. Rodents have easy access to the wiring, especially the oil level sensor.

[MX55]

Hi Barbera335,

You are 100% correct After seeing your reply, I confirmed that my engine temperature gauge is working by checking that the gauge moves as engine gets hot

This evening I checked the oil level sensor wiring from the bottom but couldn’t find any issues. It is like brand new.

With lots of curiosity, I checked the wiring from the hood and found that about 3 inches of wiring were gone as you predicted

Now I know what I need to fix. Do you know whether there is any DIY for replacing the wiring? I googled to find one, but all DIYs are about replacing Oil Level Sensor, not wiring. Is it easy to do it? Many thanks!

[Barbera335]

It is pretty simple to do. Just match the wire colors and you will be fine. Just Google 'How to splice automotive wiring' and you will see tons of options. I prefer solder but that is just me, there are many alternatives that work just as well. You don't need BMW specific instructions, wire repair is the same regardless of manufacturer.

[MX55]

Thank you, Barbera335! I looked at some videos and figured out how to fix them.

However, I am wondering whether I better purchase an entire wiring set that connects the oil level sensor and the DME and replace it. Because I lost about 3 inches of the wiring in the middle, I might be better off by replacing the entire wiring set between the oil level sensor and the DME, instead of repairing the wiring.

Is it very hard to replace the entire set? Any suggestions? Can anyone give me some instructions or tips?

[Barbera335]

Originally Posted by MX55

Thank you, Barbera335! I looked at some videos and figured out how to fix them.

However, I am wondering whether I better purchase an entire wiring set that connects the oil level sensor and the DME and replace it. Because I lost about 3 inches of the wiring in the middle, I might be better off by replacing the entire wiring set between the oil level sensor and the DME, instead of repairing the wiring.

Is it very hard to replace the entire set? Any suggestions? Can anyone give me some instructions or tips?

You could but it is a large section of the engine harness you would be replacing. Not for the faint of heart. If it were my car I would repair the wiring, just add sections of wiring as needed but I am confident in my wire repair skills. If you are not you may want to replace the harness.

[Scout10]

Splice in the missing pieces, solder using silver solder for elec applications.
use elec tape to wrap and seal the splices separately. Check sys ops
Drive on.

[MX55]

Thank you, Barbera335 and Scout10!

After figuring out the harness is a large one that are connected to many other parts, I learned that splicing is the only option I can do. However, I couldn't do it yet because accessing the wiring is not easy. I can easily fix one end from the bottom but the other end is not accessible from the bottom. To access the other end, I guess I might need to remove air intake and access from the top. Am I on the right track? Do you have any suggestions or DIY? Thank you!

[Barbera335]

Originally Posted by MX55

Thank you, Barbera335 and Scout10!

After figuring out the harness is a large one that are connected to many other parts, I learned that splicing is the only option I can do. However, I couldn't do it yet because accessing the wiring is not easy. I can easily fix one end from the bottom but the other end is not accessible from the bottom. To access the other end, I guess I might need to remove air intake and access from the top. Am I on the right track? Do you have any suggestions or DIY? Thank you!

Can you attach pictures of the damaged wiring?

[MX55]

Hi Barbera335,

I hope you can see the wiring from the picture. The disconnected parts are just below engine belt. The left side wire is connected to oil level sensor and the right side wire is connect to DME. Many thanks!

[Scout10]

That looks like nylon braided sheath over the wire, correct?
And the wire contained within. Cut the sheath back to allow you the room needed to complete repair. You can get a piece of
it at an auto parts store, push it on before the repair if there is room .....no room go without ....wrap all with elec tape then.
Take it apart enough to allow you the room to do a GOOD splice. DIY
Better a good splice then have to do it again.........later... time consuming......yep!
good luck.

[MX55]

Hi Scout10,

Yes, you are right. That's nylon braided sheath that contains wire. My only question at this point might be how to access the wiring. When I tried to access from the bottom, I couldn't reach it (I only removed the large undercover panel. Do I need to remove some other parts?). If I need to access from the hood, I guess I need to remove air intake and some other pieces. How did you access the wiring? Many Thanks!

[Barbera335]

Unplug the connector from the oil level sensor. Trace the wire back undoing wire clips along the way. This should give you the slack you need in the harness to repair the wiring. I agree this isn't an ideal location but it shouldn't be too bad once you slacken the harness.

[MX55]

Hi Barbera335 and Scout10,

Finally, I have fixed the problem. I removed the undercover panel, unplugged the oil level sensor, unclipped the wiring, and pulled out it from the car. I prepared splicing at home and accessed the other end from the hood. To access the other end, I only needed to remove the big pipe from air box to engine. After removing the pipe, I had some space to access the other end and splice the wiring.

After erasing the two error codes, the oil level sensor is working beautifully

For your information, my stealer's quote was about $400 (not exact estimate) for the fix. I am glad that I can fix it. I really appreciate your help

[DLag30]

Just experienced the same thing with one of our cars. I installed new wiring but still could not reset the service reminder. I did reset/erase fault codes/log and was able to reset it afterwards. Thanks for the info from this thread!