[Jstar007E90]

Hi guys

I’m really up a creek here.
So basically I removed the battery off my E90 to charge it up over night as I had it sitting on the driveway for a while waiting to do the reluctor rings and sensors so I thought let’s get a full charge ready to start works. Charged battery up over night put back in the morning now car won’t start hooked up my diagnostic it can not Communicate with the DME it’s completely dear I’ve done nothing apart from remove battery charge and put back in I have even been out bought a new battery nothing checked all fuses glove box and engine compartment there is no power going to the DME any help please guys getting desperate out here

Car details
E90 2005/2006
318i SE
Mileage 126000
New battery

Thank you

[gbalthrop]

Originally Posted by Jstar007E90

...I removed the battery off my E90 to charge it up over night...now car won’t start hooked up my diagnostic it can not Communicate with the DME...I have even been out bought a new battery nothing checked all fuses glove box and engine compartment there is no power going to the DME...E90 2005/2006 318i SE Mileage 126000 New battery

Welcome to the Forum!

QUESTIONS:

1) Do you have a DMM (Digital Multimeter)?
2) What is the voltage measured at the posts of the battery you removed?
3) What is the voltage measured at the post of the new battery, as installed? Don't disconnect anything, just put one probe of meter on each battery post from above, in center of terminal clamp.
4) What is the voltage measured at the "Jumpstart Terminals" under the hood? (Red Plastic Cap beside windshield washer fluid reservoir cap is Positive or B+ and Hex Pin on Right Wing is chassis ground). For future reference, use those terminals for ALL purposes in charging, or jumpstarting; NO NEED to remove battery unless you are replacing it. Disconnect Negative Battery Terminal ONLY if you need to work on electrical system (to prevent short ;-).
5) It is quite likely that you disconnected one of the Red Wires that connects the RPDP or "Rear Power Distribution Panel" which covers the battery. On my 2007 328xi, the Small Red cable just outboard of the Large Red cable has a Black Plastic "snap-in" connector to the rear of the RPDP. That small red cable provides B+ to the DME. Make sure it is firmly seated, and test for 12V+ at that fusible link of the RPDP if the DME is NOT getting 12V+ or B+. WHAT voltage measurement do you get at that socket? Where are you measuring voltage when you say "there is no power going to DME"?
6) Since your thread is titled "Cranks but no start", I presume you have 12V+ at the Jumpstart Terminals, and the Starter cranks the engine, but the engine simply does NOT fire?

If correcting an issue at the RPDP does NOT supply power to the DME, please provide the last 7 characters of your VIN so we can plug it into the TIS home page & get specific information on YOUR model. Most of us in US are NOT familiar with the 318i, and can't offer specific info without looking at proper circuits for YOUR vehicle.

George

[gbalthrop]

Here is a screenprint from Bentley showing the DME (Engine Electronics) Power Cable.
It is the Small Red Cable (4) attached to Rear Power Distribution Panel (RPDP).
It clips/snaps into the rear of the RPDP just outboard of the Junction Box B+ supply (6).

George

[Jstar007E90]

Wow George thanks for your quick reply I did check all these connections on the non serviceable panel on the battery all seemed well seated I will put my multi meter on this wire and see if I am getting 12+ from it.
I checked the relay and I am getting 12+ at pins 87 and 85 I think they were the numbers nothing on the remaining I think was pin 30
No power to the fuse within the engine bay you know where there are 5 fuses in a little case there is no power the the DME fuses when I Bridge out the relay power becomes present to that fuse but still no start and no communication to the scan tool.
Batter reads 12.7 but I will double check this when I took it off charge it read 13v

[Jstar007E90]

George now I know it’s this wire on the RPDP I will check this for voltage now

[Jstar007E90]

I have checked red cable no; 4 it is well seated and reads 12.6 at the moment voltage has dropped slightly where I have been trying to start the car I have read some where about bridging out the ground to the dme to see if this is at fault is this a good way to test to see if the dme will kick in what pins would I Bridge

Last 7 characters of VIN KW93491

Thank you

[gbalthrop]

Originally Posted by Jstar007E90

I have checked red cable no. 4 it is well seated and reads 12.6 at the moment...Last 7 characters of VIN KW93491

Using Last VIN 7, here are pertinent TIS circuits for your 318i: Voltage Supply (NOTE F54 & check that), A2076 B+ Potential Distributor, DME Relay K6300 Installation Location, Ignition Coils, Junction Box:
https://www.newtis.info/tisv2/a/en/e...supply/q5RkHQa
https://www.newtis.info/tisv2/a/en/e...ibutor/fsMPSqi
https://www.newtis.info/tisv2/a/en/e...00601/H2uag9ub
https://www.newtis.info/tisv2/a/en/e...nition/q7VmIMf
https://www.newtis.info/tisv2/a/en/e...box/1VnYK9i0zy

I would check F54 (60A) fuse on the JB (Junction Box) Fuse Panel first, as if you have power to everything else powered by Terminal 30 (see JB schematic) when you have Ignition On, you should have B+ to F54 socket, and if you do NOT have 12V+ at Pin #30 of the DME relay (Battery Power) either that fuse is bad or there is a wiring fault between that fuse and Pin 30 of DME Relay. If DME Relay is NOT powered at Pin #30, then no power to any of the 5 fuses powered by the DME Relay.

Those references to "Pin #30" of the DME Relay are the numbers stamped on the base of the relay, for a standard automotive relay with 85 & 86 being the pins/terminals that activate the relay coil/ electromagnet, 30 being battery power or B+, and 87 being the terminal which is activated or powered when the relay contacts close to bridge Pin #30/ battery power to pin 87. In the Voltage supply schematic, that Pin 30 is shown as Pin #6 of Connector X6300, and here is the "Connector View" for that Connector X6300:
https://www.newtis.info/tisv2/a/en/e...00601/CT86fHie

Please let us know what you find,
George

[vilord]

Under the battery there are two big lugs where the power feeds for the DME and for the starter/alternator go through the body panel to the exterior of the car. These have been known to fail.
It sounds like you have already verified these are okay, but i would check them just in case, make sure there is a solid connection from one side to the other of them.

[Wingnutts]

Starter solenoid??? I had the same thing on my 09 328ix earlier this year. I had to pop start it to get it running (6spd) and drove it to the Advance Auto in my town. We checked the battery and it tested good. But to be sure I swapped the battery out at the Advance Auto for a new one and still had the same problem. So I pop started it again and headed home with a new starter. Problem solved. At least for me. Maybe this will help. Good luck!

[Jstar007E90]

Originally Posted by vilord

Under the battery there are two big lugs where the power feeds for the DME and for the starter/alternator go through the body panel to the exterior of the car. These have been known to fail.
It sounds like you have already verified these are okay, but i would check them just in case, make sure there is a solid connection from one side to the other of them.

I will check these now thank you I am about to go and check the relay again but this time for earth

[Jstar007E90]

Originally Posted by Wingnutts

Starter solenoid??? I had the same thing on my 09 328ix earlier this year. I had to pop start it to get it running (6spd) and drove it to the Advance Auto in my town. We checked the battery and it tested good. But to be sure I swapped the battery out at the Advance Auto for a new one and still had the same problem. So I pop started it again and headed home with a new starter. Problem solved. At least for me. Maybe this will help. Good luck!

But the engine cranks ie turns over surly the solenoid is working if it cranks

[Jstar007E90]

So have checked these cables they are good I have tested the relay again I have a constant live and a switch live but nothing out of pin 87 I swapped out the relay for another one the same in the engine bay fuse box no joy also have no power at the fuel pump so I put 12v on the pump to check it works and it did but still no start just turns over no start obviously I’m getting no spark or fuel could leaving the battery off over night really kill my dme... also had a guy come out and put it on insta he cannot pick up the dme either any more help please guys do I change the dme I have ordered another relay but I don’t think it is that I have tried bridging the relay across pins 30 and 87 this gets power to the dme fuse (30amp) in the 5 fuse holder with in the engine bay compartment but still dme does not power up

[Jstar007E90]

sorry to revive my old tread but for future people to check this out

so i did find the fix for this in the end it was failed DME due to blocked drain in the ECU box and it flooded the DME replaced it and she came to life