First post here, very long time lurker.
2013 R56 S, N18 Engine. Owned for 4 years and I love it.

I'm at a loss here, I've covered almost all my bases and still can't solve this. Going to check DME Relay after work. I have a feeling the actual Fuel Pump Relay is faulty, but I would greatly appreciate some additional advice!

Here is an overview of all the work I've done so far (in order)

1) I replaced my fuel pump and fuel filter about 2 weeks ago, and the car wouldn't crank or start.

2) Battery was dead, replaced with new one.

3) Alternator was giving low reading, replaced with new one.

--Car started to crank, but still no start--

4) Pulled spark plugs, cylinder 1 worn down to base, replaced all 4 plugs.

5) Coil packs are about 6 months old, showing no signs of corrosion; good there.

6) Pulled the starter and bench tested it via jumper cables; motor engaged at about 60% speed, replaced with new one.

-- Still cranks but doesn't start--

​​​​​​*Identified no power getting to fuel pump (I know, late in the timeline)

7) All fuses intact, now for the big one ughhhh....

8) Pulled the inside JBE, separated the boards, Fuel pump relay has 2 pins not soldered onto the board. I soldered those back on, reconnected the boards, and reinstalled.

​​​​​--Immediately after connecting negative terminal to battery, horn starts blaring (scared the crap outta me) and fuel pump starts priming without key in ignition. I disconnected the horn connections directly at horn to spare my eardrums and my neighbors from calling the cops on me. Went back, pulled the JBE again, separated the boards, checked the connections again, still look great, reconnected the boards and reinstalled. Fuel pump still priming with power connected and no key in ignition. Car cranks, but still doesn't start; however, fuel pump stops engaging during crank procedure.

 

So the original problem before you started throwing parts at it was a crank/no start correct?

Any DTCs stored in memory?

1. Why? Did it start before you replaced the fuel pump?
3. Define low reading; what exactly were you reading?
4, what does worn down to base mean? Pic would be helpful.
5. Just because you don't see any corrosion on a coil pack doesn't mean it's any good.
6. 60% of what RPM?

Do you have a fuel pump circuit schematic?

 

Thank you for the reply!

I replaced the fuel pump because the car was having a hard time starting (multiple attempts to start; start slowly), would die while driving, and have a complete loss of power while driving.

”Low reading” is a bad term. I replaced the alternator after the new battery because I still had a no crank/no start situation, and it seemed like the best course of action.

I don’t have the spark plugs anymore, but the gap on the central electrode was close to being out of tolerance— about .50” iirc.

I’ll get a coil pack tester and run those later. I appreciate the tip!

I came up with the 60% number when comparing the old vs. new starter’s speed of engaging.

And I do not have a fuel pump circuit schematic. I’ll try and get my hands on one.

 

Also, these are the DTC’s I have showing

P0335 - Pending
Crankshaft Position Sensor A Circuit
(I actually replaced this sensor during the process, but it’s still showing. I imagine I need to drive the car a little bit to clear it)

P0461 - Pending
Fuel Level Sensor A
Circuit Range/Performance

P15B8, P15B9, P15C9, P15C8 - Permanent

 

Oh yea! A P0335 will keep the engine from starting every time because the engine computer (DME) doesn't know where the crankshaft is positioned. Driving the car won't clear the P0335 code. This is the first thing you need to have P0335 code diagnosed and repaired.

 

How do I get the DME to recognize where the crankshaft is positioned?

I've also still got the fuel pump automatically starting and not stopping when connecting the battery. Is this a symptom of a faulty fuel pump relay or a symptom of the crankshaft sensor (or some other part) sending wrong information to the DME?

 

You don't; that is the function of the crankshaft position sensor.

As for the fuel pump. That may be normal for the fuel pump to start up momentarily when the battery is connected, but I'm not sure. I'd try it on my MINI but the engine is out of the chassis at the moment. However, if you have a crankshaft position sensor issue, that may be what's causing the fuel pump to start up for a second; it's hard to tell what goes on with BMW electronics. As long as the fuel pump doesn't stay on, I wouldn't worry about it.

 

I ran into the same problem about a year ago. I had to pull the jbe 3 times. First time soldering on this job so of course I had an extra connection I created. When I put it all back in the first time it was all good for a few days then same problem. Pulled it all out cut the boards apart again resoldered the relay. When I put it all back in and started it up the windshield wipers were stuck on I had no speedometer or tach or and dash lights no power to windows. And I was at a friend's house and had to drive home late night like that. Anyways. I got it home pulled it all out cut the board pins again and saw the lil bead I had dripped. Cleaned it all up made super sure I didn't have any other drips and checked the relay connection, again all good. I hit the relay resolder area and the resoldered pins with clear finger nail polish since the pins especially were a bit lumpy after getting cut and resoldered 3 times. But haven't had an issue since. Took me at least 5 hours all three times to pull the jbe and fuses and do the work and re install. But I learned how to solder. And luckily I started here instead of starting with the high pressure fuel pump. Thank goodness for forums. Anyway hope that helps somehow. Oh yeah my car is 2011 Clubman s. But I read that the relay burning the connection is common.

 

I just pulled my board out for the 3rd time as well.. I found I had done the same where I joined 2 pins together. So I desoldered that connection, resoldered the relay pins and reassembled the board. Connected the battery and the fuel pump isn’t auto-engaging anymore. But I still have a crank/no start situation with the same error codes.

 

I work with dexder when he trader the car in I went and purchased it from the dealer before they could send it off to auction.

I have fixed the crank sensor code by running a new wire for the CPS signal wire that was shorted to ground.

LPFP HAS 6.8 bar to the pump but nothing coming out of the HPFP. After I bypassed the relay I. The JBE that’s not good. I only have 10 volts to the new volume control valve. I’m tracking it should be 12 when o jump 12v to it I hear the valve click.

I went from 78 codes to now only one P0003 fuel volume regulator control circuit low. Car will still crank but not fire and no fuel to rail hence the no fire.