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m800 cb500 sync error

PostPosted: Tue Mar 08, 2016 1:28 am
by benjamindp
hi,

While cranking the engine, the diagnostic errors says "error sync signal".
But sync/ref synchronisation is OK.

Also I don't have ignition while cranking. But everything is working fine in test outputs.
We use the bosch module 0 227 100 211.

this is the capture of the ref and sync signal.
refsync.jpg
capture
refsync.jpg (269.4 KiB) Viewed 12964 times


these are my setups for ignition and ref/sync
ignition.jpg
ignition
ignition.jpg (207 KiB) Viewed 12962 times

ref sync setup.jpg
refsync
ref sync setup.jpg (231.85 KiB) Viewed 12962 times


don't know why we don't have ignition while cranking and why we've got the sync signal error.

Re: m800 cb500 sync error

PostPosted: Tue Mar 08, 2016 9:14 am
by Stephen Dean
Hi,

Do you know why the Ref signal has a +5V offset? it is not that common to see such and offset on a Magnetic sensor. Your missing teeth are also showing up in the trace, this can lead to the tooth count being wrong and the sync position not being correctly calculated.

Re: m800 cb500 sync error

PostPosted: Thu Mar 17, 2016 10:02 pm
by benjamindp
The offset is gone now. But we still got the sync signal error.

The weird thing is that it isn't always, last week we started the engine. But now it appears continuely so we can't start the engine. Nothing is wrong with the wiring and the setup is still the same.

also when we take a capture, both signals ( ref and sync ) are good.
But when we add an chart recorder in motec for the sync voltage, the peaks aren't comming at the same time.
Sometimes we can crank it 2mins without a peak and then we got 3-4 peaks in some seconds.

Re: m800 cb500 sync error

PostPosted: Fri Mar 18, 2016 10:51 am
by AdamW
I don't think 15 teeth is enough to use ref/sync mode 7. The help file for mode 7 says that the number of teeth will effect the minimum cranking RPM that is required to allow the engine to sync so I suspect you are below that threshold. The suggested minimum is 60 teeth for 100RPM so knowing a bike engine probably cranks at about 2 or 3 times that I would think want more like 24 or 36 teeth.