Navigateraw

Hello Everyone. I have had an issue with my E61 for a couple of months. After coming back to my 520d after shopping it would crank up but not start, presuming it was a battery issue, I looked in the boot and saw a couple of inches of water in the battery compartment and presumed this was the fault, pulled out the battery and dried the area, unplugged the terminals for 10 minutes and reconnected for it to get me home 80miles away. I had to unplug the battery on a few occasions to get around as the auto electrician scheduled me in for 10 days ahead. In the meantime the car would not start . took it to the auto electricians who mentioned he was unable to "read it" but said it would need an ECU as that was the fault. He felt the battery compartment water ingress was not the main issue and was a coincidence Unfortunately a new ECU did not correct the issue and the auto electrician . He mentioned the battery needed changing which I did. I have managed to download ISTA+ and get a scan completed, I will list the diagram below. It initially flagged up 27 faults of which 3 will not delete ( images below)

I have had issues with the key in the past, where, on occasion it would not go into the slot ( transponder type key) so not sure if this is an issue. As you will see from the diagram the DSC and DDE are in red and will not correct using the program. I need some direction in regards to what I need to check on the car. The auto electrician mentioned he had checked all the fuses. Is there a possible misalignment issue. Do these vehicles have some sort of anti theft mode ?The car key works after many presses to open the car. It does not make the sound it usually makes when inserted into the slot. Is there any relays I can check to see if they have corroded which is not letting the car start or could it be a starter motor issue ? Any advise would be much appreciated. I have emptied the boot and all the electrical equipment in there is completely dry ( picture below). I will include as many pictures as possible, Unfortunately I am not an expert using ISTA+ so will need some direction. Your advise will be much appreciated.


scan results

initial faults part1

initial faults part 2

main issues

boot

in car

Greggo

Hello. Well you certainly have some work to do.

My guess, you have something that is probably fairly simple to fix once you find the culprit. Something interfering with the communications bus. This is causing problems with several modules.

I would start with the two modules in red (DSC and DDE,) these are not communicating and need attention. The modules in yellow have errors, but they are communicating, ignoring these for now.

Find the red modules and look for signs of water damage, wiring issues etc. If the issue is not obvious, it can take some time and effort to locate the cause. Could be simple as a bad ground. Could be a bad module taking the system down. But always look for the simplest explanation first. One little wire or one bad module, can take the entire system down.

Best of luck.

donpb

Check your battery storage voltage after not running the car for a bit. Let us know what voltage you measure.

Navigateraw

The voltage is about 12.2volts

donpb

Not too bad but a tad bit low.

Now its time to check it under load, I have a sticky here, Is My Battery Bad? - 5Series.net - Forums, but if you want to not go further with the battery, its up to you. The test is pretty simple though.

Navigateraw

The battery is new, I wont be able to check the battery when the ignition is turned ON as it will not start. I did however run ISTA today and after running a diagnostic it mentioned "The above signal indicates a short circuit to positive" I also noticed that something had broken off the battery terminal, do you know what has broken off and is it of any significance . ( sorry for the massive image) is this some sort of earthing cable ?

donpb

That looks like someone might have tapped the + terminal to power an accessory device.

Navigateraw

Could the tapping cause an issue with the DSC/DDE ? and cause the engine to not fire up. I have been absorbing a whole load of YouTube content trying to find what could be the issue, Does anyone know the significance of this item below which is situated on the fuse box near the battery ?

donpb

Try not to get information overload. Even though things look dry, there still could be issues caused by that water ingress. You might want to have an indy electrical specialist diagnose it for you.

Navigateraw

it was with an auto electrician for 3 weeks. Someone who's been in the game for over 25 years. he couldn't get the ECU to communicate