Multiple error codes

Yep, the trouble code P0393 means the PCM has detected a high voltage reading from the camshaft position sensor for camshaft sensor B in engine bank 2. Here is how you can change out the sensor with instructions and location in the diagrams below. After you change the sensor out clear the codes and drive it to confirm the sensor was the problem.
Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.

Thanks Ken. Can you tell me, facing the engine, which side this one is on and if it's the one on top and closer to the front or the one further back and lower?

Thanks,

Sam

Sure, facing the engine it will be on the left side.

Top or bottom one?

Where it says #2.

Hi Ken,

Here's what I've done and where I'm at on this:

Originally, I was getting the code p0391. I replaced the sensor on the right side of the vehicle (looking at the engine from in front of the car) and lower of the two.

After this I got the code p0393.

Thinking I had replaced the wrong sensor, I removed the left, lower one and replaced it with the used one I had removed the first time.

Then the codes were p0393 and p0368.

I ordered a new sensor and replaced the left, lower one with the new one, meaning I have now replaced the lower sensors on both sides and haven't touched the upper ones.

Current codes are p0393 and p0365.

In addition to the codes, I've noted during this process, there have been various misfire and lean running codes.

So, give me some expertise on this if you would please.

Thanks so much,

Sam

The code is for a circuit issue, we will need to check the wiring from the sensor to the ECU. This guide will show you how and I have the engine wiring harness diagrams to help you see which wires to test. How is the condition of the sensor connector?

https://www.2carpros.com/articles/how-to-check-wiring


Check out the diagrams (below). Please let us know what happens.

Okay, getting no reading at the plug. Possibly a fuse, and if so, which one?

Thanks,
Sam

Good find, check the fuses in the front # f008, f009, f003 and f004 and rear fuse panel f001, f002, f006 and f005. Here is a guide to help you:

https://www.2carpros.com/articles/how-to-check-a-car-fuse


Please run down this guide and report back.

Okay, I may be mistaken.

I checked all the fuses and they're all working properly.

I posted on the Bimmerfest forums and got a couple of responses when I queried which specific fuse was for the sensors. I got the following two replies:

"There is not one. Position sensors are supplied by DME"

and

"I searched yesterday for about an hour and even looked at the wire diagrams and nothing shows its connected to a fuse."

After this I tried a tester light on the plugs, and both showed connection in one of the three prong holes. I retried my multimeter and got nothing which may mean that the cheap meter I have just is messed up.

Where should we go from here?

I looked at the schematics you sent me and couldn't decipher where the wiring goes back to from the sensor, but if I'm getting power through the plugs to the sensor as indicated by the test light, which would indicate that it's not a wiring issue, right? Or could it be an improper ground where the two ground wires come back together?

As I'm sure you can tell, I'm a real babe in the woods on all this, and I'm sorry if I'm asking simple questions. I am trying to learn and am willing to do whatever work is necessary if I know what it is.

Thanks so much,

Sam

Sam,

I noticed you haven't been contacted for a few days. Have you been able to make any progress? I did read through the last post.

I'm not 100% sure exactly what is happening, but I'll try to answer your questions.

If you are getting power through a wire, the wire is good. Are you getting the correct amount of power is the question?

Next, a faulty ground can certainly cause issues as well.

I noticed that Ken suggested checking fuses. In addition to checking the fuses, did you confirm there is power to and from them?

Let me know.

Take care,

Joe

Hi Joe,

Yes, all the fuses are good.

I'll get a new multimeter and see how much voltage is running through the plugs and we'll go from there.

Thanks,

Sam

Okay, I'm getting between 20.4 - 21.6 on both sides.

Hi,

Which wires are these? There really isn't anything on the vehicle that should have 20+v. Let me know.

Joe

It's the plugs that connect into the camshaft position sensors.

Sam, that is either the problem or the reading was incorrect. The sensor is called a hall effect sensor. A signal voltage is provided by the PCM which is usually around 5v. The sensor (via a magnet) produces a signal when it turns. The signal can't produce that much. Actually, nothing on the vehicle should be doing that.

When the alternator is charging, I've seen output slightly over 14v. If it goes over 15.2, then suspect there is an issue with the regulator. With that in mind, I want you to confirm the alternator isn't overcharging. Something isn't adding up.

Here is a link that explains how to test the alternator. You will need the new test you got:

https://www.2carpros.com/articles/how-to-check-a-car-alternator

Let me know.

Joe

Hi Joe,

I'm attaching some photos. Please bear with me, electrical work isn't something I've ever really done although I'm trying to learn and I am absolutely willing to do whatever is required to do that.

I made these measurements with the ignition turned on, but the car was not running.

I thought perhaps I had the multimeter on the wrong setting, so I changed it (see picture).

I probed the positive into alternate sides of the plugs as shown and got the corresponding readings as shown.

Please, if you would, let me know if I'm doing anything wrong. One of the four readings, as you can see, was noticeably lower than the other three. I double checked to make sure.

Thank you so much for your patience.

Sam

Those readings look correct, you may have a PCM that is going out. To confirm, let's do a CAN scan to see what it brings up. here is a guide and video that will help us see what's going on:

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

Please let us know what you find.

Ken,

Is the CAN scanner linked in the article you sent, which is listed on Amazon, going to do what we need?

Thanks,

Sam

Yes, it will scan the CAN system.

Okay Ken,

I'm attaching a screenshot.

The current codes are as follows:

P0458
P2092
P2094
P0365
P0348
P0393
P0300
P0301
P0305

Please let me know if this is what we need.

Thanks,

Sam

Yes, this is pointing to the DME module being bad, here are instructions on how to replace the unit. Check out the diagrams (below). Please let us know what happens.

Hey Ken,

In looking at your reply and the attached images, I'm not seeing any instructions for replacing the module.

Am I just missing it?

Thanks,

Sam

This is all they offer as far as instructions go, did it fix the problem?

The part is being shipped out to me today. Luckily, I found a great deal on a used one. I'll let you know.

good job, let me know.

Okay, swapped out the part and the engine turns over but won't start, which is new.

It's giving me the following codes:

P0458
P2092
P2094

I erased the codes and am charging the battery and will see what codes show up after that.

I'm confident that I installed it correctly, but if it still won't start I'll go back in and double check, reinstall the old one to see if it starts with that one, etc., to try to troubleshoot.

Reinstalled. Same results. Put the old one back in, started right up, but of course with a bunch of error codes:

P0458
P2092
P2094
P0365
P0348
P0393
P0300
P0301
P0305

So, it looks like I bought a bad DME. I'll find another one and try again.

Sounds good, let me know.

Ken, these DMEs have to be programmed to the car, no? Isn't that why it wouldn't start?

Yes, they need to be programmed to the car, many online services can do this for you.