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E70 crank no start when warm
Posted: Thu Jul 20, 2023 11:54 pm
by Zed Dee
Help please! New to the forum.
2009 BMW X5 E70 M57 engine - crank no start when engine is warm. Changed fuel pump, fuel pump control module, all 6 injectors, MAF sensor, air intake sensor, crank position sensor. The codes I was getting was 4BA1 and 4BC7 but they disappeared once the MAF and intake sensors were replaced. No other codes coming up on ISTA. When it's cold it starts without any issues. Once engine is warm, it cranks and cranks but won't start. I have to leave it for an hour or so before it starts. Any help will be appreciated.
E70 crank no start when warm
Posted: Fri Jul 21, 2023 5:50 am
by Alan Gunn
Where they new injectors as i had this same problem and needed 2 injectors.
Cam-sensor didn't see that in your list sometimes don't show a code.
E70 crank no start when warm
Posted: Fri Jul 21, 2023 7:35 am
by Zed Dee
Hi. Reconditioned injectors. Not sure where the camshaft sensor is on the E70.
E70 crank no start when warm
Posted: Fri Jul 21, 2023 8:24 am
by X5Sport
Camshaft speed sensor B6219…..
- IMG_2712.jpeg (105.48 KiB) Viewed 13826 times
E70 crank no start when warm
Posted: Fri Jul 21, 2023 8:56 am
by Zed Dee
Thank you... I'll try that next. Just surprised it's not throwing any codes. Had it checked by two garages also but they couldn't find any codes relating to the symptoms.
E70 crank no start when warm
Posted: Fri Jul 21, 2023 10:08 am
by X5Sport
It should be throwing codes….
Hall sensor, camshaft
The camshaft Hall-effect sensor is mounted at the top front of the cylinder head cover. A rectangular lobe which moves past the Hall-effect sensor is located at the front of the camshaft. The DDE control unit evaluates the resulting voltage signal (one square-wave signal per camshaft revolution). This signal is used for synchronization purposes:
Synchronization sequence:
when the engine is started, the DDE control unit detects from the camshaft signal whether a cylinder is at TDC on the compression or exhaust stroke. At the same time, the crankshaft sensor signal must be detected in the correct sequence.
Only if those signals are correctly detected can the DDE control unit activate the correct injector at the correct time.
Engine start is not possible without synchronization!
Troubleshooting
The following faults are monitored:
3EC0, No camshaft sensor signal
3EC1, Camshaft sensor signal incorrect
3ED0, Temporary loss of camshaft sensor signal
3ED1, Camshaft sensor signal temporarily incorrect
In addition, the speed difference between the camshaft and crankshaft is monitored
Consequences:
In case of failure during engine operation: No effect; however, the next time an attempt is made to start the engine, it will not start.
E70 crank no start when warm
Posted: Fri Jul 21, 2023 10:09 am
by X5Sport
Engine speed detection Digital Diesel Electronics V7
Two sensors are used to detect the engine speed and the position of the camshaft and the crankshaft:
Crankshaft sensor. The DDE control unit uses the crankshaft sensor signal to calculate the precise engine speed and to detect the TDC positions of the crankshaft.
Camshaft sensor: On the basis of the camshaft sensor signal, the DDE control unit detects the current TDC setting.
For starting the engine, the DDE control unit checks the following conditions:
* the two signals must not have any faults
* the signals must be detected in a specific chronological sequence
(This process is referred to as synchronisation and is only performed when the engine is started)
Effects of faults on the signals:
* Camshaft sensor signal not OK: Engine can be started, but starting takes longer, no effect when engine is running
* Crankshaft sensor signal not OK: Engine start via camshaft sensor signal possible with some versions; when the engine is running, the camshaft sensor signal is used and the torque is limited
Brief component description
Crankshaft sensor The crankshaft sensor is mounted at the rear of the crankcase. The DDE control unit provides the sensor with an earthing point (M_KWG) and a supply voltage of 5 V. The crankshaft sensor is designed as a Hall effect sensor.
On the crankshaft there is an increment gear which has 58 small permanent magnets around its perimeter. As the crankshaft rotates, these permanent magnets move past the crankshaft sensor, thereby producing the crankshaft sensor signal.
Note for N57: The crankshaft sensor on N57 is also able to identify the direction of rotation of the engine. This enables a faster engine start.
Camshaft sensor: The camshaft sensor is mounted at the top rear of the cylinder head cover. The DDE control unit provides the sensor with an earthing point. The camshaft sensor is supplied with vehicle voltage via the switched terminal 87. The camshaft sensor is designed as a Hall sensor.
There are three different segments at the back of the camshaft and these move past the camshaft sensor. The DDE control unit evaluates the resulting voltage signal (three different square-wave signals per camshaft revolution).
E70 crank no start when warm
Posted: Fri Jul 21, 2023 2:48 pm
by Leslie
It's Definately worth changing the cam sensor just to see as its not expensive and it certainly gives hot starting issues if faulty, sound like an expensive nightmare after that parts list.
E70 crank no start when warm
Posted: Fri Jul 21, 2023 2:57 pm
by Zed Dee
X5Sport wrote: ↑Fri Jul 21, 2023 10:09 am
Engine speed detection Digital Diesel Electronics V7
Two sensors are used to detect the engine speed and the position of the camshaft and the crankshaft:
Crankshaft sensor. The DDE control unit uses the crankshaft sensor signal to calculate the precise engine speed and to detect the TDC positions of the crankshaft.
Camshaft sensor: On the basis of the camshaft sensor signal, the DDE control unit detects the current TDC setting.
For starting the engine, the DDE control unit checks the following conditions:
* the two signals must not have any faults
* the signals
must be detected in a specific chronological sequence
(This process is referred to as synchronisation and is only performed when the engine is started)
Effects of faults on the signals:
* Camshaft sensor signal not OK: Engine can be started, but starting takes longer, no effect when engine is running
* Crankshaft sensor signal not OK: Engine start via camshaft sensor signal possible with some versions; when the engine is running, the camshaft sensor signal is used and the torque is limited
Brief component description
Crankshaft sensor The crankshaft sensor is mounted at the rear of the crankcase. The DDE control unit provides the sensor with an earthing point (M_KWG) and a supply voltage of 5 V. The crankshaft sensor is designed as a Hall effect sensor.
On the crankshaft there is an increment gear which has 58 small permanent magnets around its perimeter. As the crankshaft rotates, these permanent magnets move past the crankshaft sensor, thereby producing the crankshaft sensor signal.
Note for N57: The crankshaft sensor on N57 is also able to identify the direction of rotation of the engine. This enables a faster engine start.
Camshaft sensor: The camshaft sensor is mounted at the top rear of the cylinder head cover. The DDE control unit provides the sensor with an earthing point. The camshaft sensor is supplied with vehicle voltage via the switched terminal 87. The camshaft sensor is designed as a Hall sensor.
There are three different segments at the back of the camshaft and these move past the camshaft sensor. The DDE control unit evaluates the resulting voltage signal (three different square-wave signals per camshaft revolution).
This is very helpful. Thanks again. I'll change the sensor and see how it goes.
E70 crank no start when warm
Posted: Fri Jul 21, 2023 3:00 pm
by Zed Dee
Leslie wrote: ↑Fri Jul 21, 2023 2:48 pm
It's Definately worth changing the cam sensor just to see as its not expensive and it certainly gives hot starting issues if faulty, sound like an expensive nightmare after that parts list.
Thank you. And yes, it's been expensive but on the plus side I've learnt a lot and saved on labour cost. And I'm still learning through this forum.
E70 crank no start when warm
Posted: Wed Aug 02, 2023 11:40 pm
by H4MP
did the camshaft sensor fix the issue ?
E70 crank no start when warm
Posted: Thu Aug 03, 2023 9:13 am
by Zed Dee
H4MP wrote: ↑Wed Aug 02, 2023 11:40 pm
did the camshaft sensor fix the issue ?
Hi. I managed to get the sensor from BMW on Monday but only managed to install it yesterday. I've not had the chance to drive the vehicle yet but I'm hoping to test it out today.
E70 crank no start when warm
Posted: Sat Aug 05, 2023 12:58 pm
by Zed Dee
Update: the camshaft position sensor appears to have emilimated the starting issues. Thanks guys. But why were there no fault codes being read by the various diagnostic tools? Not that it matters now coz the car seems to start as it should. Thanks again.
E70 crank no start when warm
Posted: Sat Aug 05, 2023 5:17 pm
by Leslie
I guess as it got worse it would be logged , I know I was looking for codes before and they disappeared as soon as the key was taken out so I had to leave it running after it appeared to find the code
The fact it only appears when hot could be the reason too and was fine when cold . If its sorted it that's good
E70 crank no start when warm
Posted: Sat Aug 05, 2023 6:53 pm
by X5Sport
for it being sorted. No codes is one of my pet hates. Not much good in having error logging if it doesn’t then log errors!
