Reduced Engine power - no fault code

Hi Everyone

I am new to the BMW scene so please forgive my ignorance. My girlfriend has a 05 745li with 125k miles on it. The check engine light and reduced engine power lights came on last week on the car. She had the car taken to what she thought was a reputable shop in the are. They called a few days alter saying it was a crank sensor and the car was ready to pick up. Picked the car up and made it 20 miles and the same thing again

Called the shop back, in my opinion very un helpful and pushed it back saying well the car does have a lot of miles on it so things do break.

At this point I borrowed a stnadard OBDII scanner and there are no codes showing on the car. The car is in limp mode and will not move for than 5mph or so.

I did search the forums and found some "open ended" discussions that didnt seem to have a real resolution.

Basically the car has an irratic idle at this point, between 700 and 1300 per the Generic OBDII scanner I have. The Reduced Engine power light is on, but no standard OBDII fault codes present.

Are there BMW specific codes for the Reduced Engine Power that cannot be read with a generic scanner?

Has anyone else had this problem? If so what was the resolution?

Thanks in advance for any help!

You need to use a proper scaner, or get BMW INPA / DIS to do a scan.

You can buy one of the cheap cable kits on ebay and just use a laptop.

If it doesn't save a standard code it shouldn't be anything too serious (or at least not something the car things is too serious). That doesn't mean it cant be something more important, but hopefully the major components arent reporting faults.

i would check two things #1 Throttle body #2 DME disconnect battery for a few hours and then reconnect,if it is DME your car wont start again 99%. Reduced Engine power light is safe mode when only half cylinders are working and recorded by DME. Once you erase it by disconnecting the battery, it wont readjust again and will shot off cylinders and prevent car fro starting. I would be able to crank the engine,but that is all. That are only 2 things i can relate to Reduced Engine power light

Originally Posted by Khabar

i would check two things #1 Throttle body #2 DME disconnect battery for a few hours and then reconnect,if it is DME your car wont start again 99%. Reduced Engine power light is safe mode when only half cylinders are working and recorded by DME. Once you erase it by disconnecting the battery, it wont readjust again and will shot off cylinders and prevent car fro starting. I would be able to crank the engine,but that is all. That are only 2 things i can relate to Reduced Engine power light

Im assuming DME is the engine management / ECU?

I just want to understand correctly. If the car wont start after reconnecting the battery this is possibly a bad DME?

more likely. Try it. it not going to hurt more than it is now

Originally Posted by Khabar

more likely. Try it. it not going to hurt more than it is now

I ordered a cable and software from amazona nd am having it saturday delivered so I can take a look at it. After fighting with the shop they are willing ot look at it for free, if I can get it to them, this is after having it towed there the first time and them having the car for a week.

Hey guys I finally got a chance to work on this. It appears I am getting a P060A code. This code simply says "Internal Control Module Monitoring Processor Performance". Has onyone else had this issue? Should I just replace the DME? And if so, can I now program it with the cable / sofware I have?

Thanks!