[gogoshkin12]

Hello there,

I have a 5 series F10 2010 525d with N57D30 engine,the issue is that it doesn't start:

Fault codes:

1. CD951C - no message /actual steering torque/ - not relevant due to the steering module/motor is dead for some reason
2. 28CE00 - GSC, Lin Bus communication fault
3. 273C00 - Camshaft Sensor, Signal, No Signal
4. 25CD00 - Rail Pressure Control Valve, Activation, Short Circuit to Ground
5. 28D600 - Air Mass Flow Sensor, Signal, Open Circuit or Short Circuit to Ground
6. 25AD00 - Supply Control Valve Activation, Short Circuit to Ground
7. 249F00 - Boost Pressure Actuator/Turbine Control Flap, Actuation, Short Circuit to Ground
8. 249300 - Rail Pressure Monitoring on Engine Starting, rail pressure too low

So far checked:

1. The fuel pump is creating and holding pressure of ~4.2 bar even when cranking
2. When running the bleeding procedure fuel goes to the rail
3. Changed the cam shaft sensor
4. Changed the Rail pressure control valve
5. Checked the fuses all powered and operational
6. While cranking:
- Rail pressure control Valve Activation Values - 17.2% no cranking / 76% peak while cranking
- Rail Pressure actual value - 120 psi no cranking / 192 peak while cranking
- Pre -supply pressure - 0.3 mbar no cranking / 4000+ mbar while cranking
- Delivery Control Valve Activation - 26% no cranking / 82% while cranking

I have a snapshot of the readings if required.

One thing that crossed my research was that according to TIS wiring all these should be powered by F22 on the JB, but on my vehicle there is an empty slot for F22 also there is no wiring for it!

Any thoughts and ideas will be highly appreciated

Thank you

[Kwood-F10-535i]

It seems like either a main harness wire from the ECU is damaged or partially connected. or The ECU is dead.

Here is the ECU wiring
https://www.newtis.info/tisv2/a/en/f...onics/F7cYql53

Here is the wiring for the engine.
https://www.newtis.info/tisv2/a/en/f...-electronics2/

[Kwood-F10-535i]

Here is the info on the GSC LIN error

https://www.newtis.info/tisv2/a/en/f...ystem/DgvWBPtv

[Kwood-F10-535i]

All your issues are connected to systems on this cable to the ECU. X20008

https://www.newtis.info/tisv2/a/en/f...d-lim/q-X20008

I would start there and check the connector then chase down the harness and inspect for damage.

Well I have to get back to work. Hope this helps. PM me if you have any questions or post here. I cant guarantee I can respond till after 5pm Eastern time USA. Good Luck

[gogoshkin12]

Originally Posted by Kwood-F10-535i

Here is the info on the GSC LIN error

https://www.newtis.info/tisv2/a/en/f...ystem/DgvWBPtv

Thank you for the fast reply, regarding this error, I forgot to mention that it's common fault so I haven't even checked yet, but worth the try swapping the preheat module with working one just to rule it out.

Thanks

[gogoshkin12]

Originally Posted by Kwood-F10-535i

All your issues are connected to systems on this cable to the ECU. X20008

https://www.newtis.info/tisv2/a/en/f...d-lim/q-X20008

I would start there and check the connector then chase down the harness and inspect for damage.

Well I have to get back to work. Hope this helps. PM me if you have any questions or post here. I cant guarantee I can respond till after 5pm Eastern time USA. Good Luck

Hello there,

According to what you've sent like link, it comes up as X20009 that holds most of the high fuel pressure side failures, on X20008 there is connection for low fuel pressure and Hot air mass.
But still doesn't add up because when I click on separate wiring it always leads to F22, which again I don't have, so I'm assuming that potentially I have a dead ECU ground or something, I've checked all the wiring and it starts and ends where it should.

What I'm thinking of is to jump the fuel regulating valve and check if it will start building pressure so I can confirm potential ECU failure.

Thank you

[Kwood-F10-535i]

Originally Posted by gogoshkin12

Hello there,

According to what you've sent like link, it comes up as X20009 that holds most of the high fuel pressure side failures, on X20008 there is connection for low fuel pressure and Hot air mass.
But still doesn't add up because when I click on separate wiring it always leads to F22, which again I don't have, so I'm assuming that potentially I have a dead ECU ground or something, I've checked all the wiring and it starts and ends where it should.

What I'm thinking of is to jump the fuel regulating valve and check if it will start building pressure so I can confirm potential ECU failure.

Thank you

https://www.newtis.info/tisv2/a/en/f10-520d-lim/XDoGTHI

If you do jumper the valve to 12V do it only for a second or 2. There is a possibility for the rail pressure to exceed safe pressures if done too long.

Do you have access to a laptop and ISTA?

[gogoshkin12]

Originally Posted by Kwood-F10-535i

https://www.newtis.info/tisv2/a/en/f10-520d-lim/XDoGTHI

If you do jumper the valve to 12V do it only for a second or 2. There is a possibility for the rail pressure to exceed safe pressures if done too long.

Do you have access to a laptop and ISTA?

Yes, when I'm running the service for low rail pressure... it's showing no pressure building like it does when the valve is not powered, so I had one spare and got it swapped, but no luck, strange is that all them errors started coming gradually, they didn't come at once, now they're always there.

What is your thought about ISTA etc?

Thanks

[Surly73]

Originally Posted by gogoshkin12

Yes, when I'm running the service for low rail pressure... it's showing no pressure building like it does when the valve is not powered, so I had one spare and got it swapped, but no luck, strange is that all them errors started coming gradually, they didn't come at once, now they're always there.

What is your thought about ISTA etc?

Thanks

I'm no expert on your specific repairs, but my impression after reading the thread (even before I read the post that mention this) is damaged wiring. There are a lot of "short to ground" in there explicitly reported by working modules in the car.

Maybe you've already done this, but if I was chasing this problem I would put down the computer and the spare sensors, get some tools, and start checking around the various harnesses and connectors you've identified. I realize you have some discrepancies in fusing and connector numbers in TIS, but I think it's still worth a look. Maybe a rat took a big chomp and that's responsible for everything.

[gogoshkin12]

Originally Posted by Surly73

I'm no expert on your specific repairs, but my impression after reading the thread (even before I read the post that mention this) is damaged wiring. There are a lot of "short to ground" in there explicitly reported by working modules in the car.

Maybe you've already done this, but if I was chasing this problem I would put down the computer and the spare sensors, get some tools, and start checking around the various harnesses and connectors you've identified. I realize you have some discrepancies in fusing and connector numbers in TIS, but I think it's still worth a look. Maybe a rat took a big chomp and that's responsible for everything.

Hello,

Worth the try, will check again the wiring tomorrow and will update.

Thanks

[gogoshkin12]

Update
All wiring checked, in good order, there is no ground on the rail regulator plug.
I've borrowed ecu set from a friend's car and errors are gone as well as there is constant ground on the rail reg plug, but the ecu comes from automatic f10 GT with 3.0d engine configuration so in my case there is only one sec crank. Don't want to get it coded to my vehicle because it's from a working car so will order new/used one and will update.

Thanks

[gogoshkin12]

Hello again,

Changed the ecu, changed the crank sensor, checked all the wiring with no luck. My last and only thought is the high pressure pump, can't see anything else that could be causing the issues. Although it's loosing sync between the cam and the crank while cranking, but with easy start sprayed in the intake the engine starts running in a smooth way, which from my point of view is excluding chain issues. Any thoughts would be highly appreciated
Thank you

[gogoshkin12]

On the high pressure pump valve and rail fuel regulator valve its showing 3.5v with ignition on, I think should be more? Thanks

[razfrankel]

What could cause no crank no start if not the battery? Maybe electrical problem?