merctec Posted September 25, 2022 Report Share Posted September 25, 2022 Hi Just to try I put a 2.4k external resister on my trigger 1 cherry sensor and set the pull up in the ecu to off engine wont start trigger scope no trigger 1 signal runtime no trigger 1 on oscilloscope sensor has a signal even if i crank by hand and check voltage it is switching up and down on ecu runtime values no trigger 1 and no errors either remove resister and reset ecu to pull up on engine now starts and it ran for about 12min cut out re started and ran for another 10 min or so cut out when it cuts out or misfires when running it logs an error in runtime trigger values after it cut out 2nd time when cranking ecu no trigger 1 on runtime or on trigger scope but ok on oscilloscope and cranking by hand. Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 25, 2022 Report Share Posted September 25, 2022 I have moved your post as it was not related to the firmware subject you were posting in. Can you please explain the problem better - why are you fitting an extra pull-up? what engine and ECU do you have? Can you attach your tune and log and the trigger scope. Quote Link to comment Share on other sites More sharing options...
merctec Posted September 25, 2022 Author Report Share Posted September 25, 2022 Hi Sorry still trying to get used to this posting gig It is in relation to my ongoing efforts to get to the bottom of my non start and cutting out issue which i posted in the pc link and firmware 6.20 topic which was intermittent eg event only on 2 occasions which since i updated the firmware is now a permanent issue i have already sent scope pics and logs can send more if needed Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 25, 2022 Report Share Posted September 25, 2022 10 hours ago, Adamw said: Can you attach your tune and log and the trigger scope. Quote Link to comment Share on other sites More sharing options...
merctec Posted September 26, 2022 Author Report Share Posted September 26, 2022 Attached trigger scope when not starting and tune as it is now log too big to attach scope26 non start.llgx cutting out tune.pclx Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 26, 2022 Report Share Posted September 26, 2022 Yeah, you have no trigger 1 signal at all, and trigger 2 is picking up some noise. No trig 1 signal would likely be either a wiring or sensor issue. Trigger 2 is probably just the arming threshold too low. Also trigger 1 edge should not be set to all. Typically falling is best for most hall sensors. Quote Link to comment Share on other sites More sharing options...
merctec Posted September 26, 2022 Author Report Share Posted September 26, 2022 Had it falling but was playing with the settings to see if it changed anything as i did by fitting a external 2.4k resister to try to narrow down the issue the thing is trigger 1 has a signal right up to the wire at the control unit plug it's just not picking it up Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 26, 2022 Report Share Posted September 26, 2022 10 hours ago, merctec said: the thing is trigger 1 has a signal right up to the wire at the control unit plug it's just not picking it up How are you testing this? Quote Link to comment Share on other sites More sharing options...
merctec Posted September 28, 2022 Author Report Share Posted September 28, 2022 Measured it with a Pico scope do you have a drop box it is also throwing 1047 and disconnecting a lot from the pc link Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 28, 2022 Report Share Posted September 28, 2022 I dont have dropbox. If you have it stored in there you should be able to generate a share link for the files. Quote Link to comment Share on other sites More sharing options...
merctec Posted September 28, 2022 Author Report Share Posted September 28, 2022 https://drive.goohttps://drive.google.com/file/d/1YMDOhsWQtmkyh-ZvOxnzNdJ9xOZlofNm/view?usp=drive_webgle.com/filehttps://drive.google.com/file/d/1B3izsbR5f90OYgrBnVq0gbEJZZFLmsDR/view?usp=drive_web/dhttps://drive.google.com/file/d/1i75cBsJrdiLYqxGziSNC5mVXl40b-XTR/view?usp=drive_web https://drive.google.com/file/d/1i75cBsJrdiLYqxGziSNC5mVXl40b-XTR/view?usp=drive_web Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 29, 2022 Report Share Posted September 29, 2022 Unfortunately the google links are restricted. You will need to go back into drive then sharing settings and set it to something like "anyone with link". Quote Link to comment Share on other sites More sharing options...
merctec Posted September 29, 2022 Author Report Share Posted September 29, 2022 Sorry try it now Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 29, 2022 Report Share Posted September 29, 2022 It looks like you've possibly got a bad ground. In the video showing the waveform on the pico you can see the waveform only comes down to about 2-2.5V. The bottom of the waveform should be sitting on or close to ground (0V). The ECU wont accept an edge as a valid tooth unless it falls below 1.0V. So, either the ground connection between the ecu and sensor is bad - or the ground connection from ecu to engine/batt is bad. Quote Link to comment Share on other sites More sharing options...
merctec Posted September 29, 2022 Author Report Share Posted September 29, 2022 The earth from the sensor ground wires too the engine is 0.5 ohms resistance too body 0.6 and ecu plug too engine on the 2 black wires is 0.5 ohms and to the body is 0.6 but in the pursuit of an answer i did disconnect them at the sensor ends and ran them straight to the engine just to rule out a wiring issue with no change in symptoms and i have also swapped the ZF cherry sensor with another one with no change Quote Link to comment Share on other sites More sharing options...
merctec Posted September 30, 2022 Author Report Share Posted September 30, 2022 13 hours ago, merctec said: The earth from the sensor ground wires too the engine is 0.5 ohms resistance too body 0.6 and ecu plug too engine on the 2 black wires is 0.5 ohms and to the body is 0.6 but in the pursuit of an answer i did disconnect them at the sensor ends and ran them straight to the engine just to rule out a wiring issue with no change in symptoms and i have also swapped the ZF cherry sensor with another one with no change the lower voltage is the reason i tried to run with the external pull up resistor to see if that changed anything which it did engine wont start when swapped back to internal pull up resistor engine starts but still cuts out as before power supply to ecu always on battery voltage when faulting sensor supply voltage always on battery voltage when faulting Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 30, 2022 Report Share Posted September 30, 2022 If you back probe the trigger 1 pin with a voltmeter at the ecu header, then slowly turn the engine by hand, what are the 2 voltage levels you see on trig 1 pin? Quote Link to comment Share on other sites More sharing options...
merctec Posted September 30, 2022 Author Report Share Posted September 30, 2022 Just checked 4.19V high low 25.7mv Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 30, 2022 Report Share Posted September 30, 2022 So that would be fine now. But the problem is your scope showed it only going down to ~2.0V yesterday which would not be fine. So possibly an intermittent issue - or possibly you have a large ground offset when the starter motor is pulling current. If you connect your voltmeter to the neg battery post and the engine block, how much voltage drop do you see when cranking? Anymore than about 0.2V is usually considered an issue. Quote Link to comment Share on other sites More sharing options...
merctec Posted September 30, 2022 Author Report Share Posted September 30, 2022 will check that tomorrow when i crank by hand when the engine cuts out and wont re start the high voltage is in the 2.5v area and less than a volt on low side Quote Link to comment Share on other sites More sharing options...
merctec Posted October 1, 2022 Author Report Share Posted October 1, 2022 Voltage drop when cranking 0.391V Cleaned up engine and battery ground now 0.157V did the crank by hand again after 4.18V drops too 14.3mv Quote Link to comment Share on other sites More sharing options...
merctec Posted October 3, 2022 Author Report Share Posted October 3, 2022 Iam fresh out of ideas have tried everything I can think off to find this fault Assuming i have a trigger1 and 2 signal stable power and earth to the ecu what else would stop the ecu giving the spark and injector pulse have disconnected all non-essential stuff eg tacho, fan control Quote Link to comment Share on other sites More sharing options...
Adamw Posted October 3, 2022 Report Share Posted October 3, 2022 5 hours ago, merctec said: Assuming i have a trigger1 and 2 signal stable power and earth to the ecu what else would stop the ecu giving the spark and injector pulse You dont have stable trigger 1 signal though. Your trig two looks ok in all data you have given so far, but both the ECU trigger scope and your standalone oscilloscope show a trig 1 signal that is not meeting the required voltage thresholds. A hall sensor must rise above 1.5V and fall below 1.0V to be considered a valid edge. A hall sensor is a pretty simple device - all it effectively does is connects the signal wire to ground when metal is in front of it - so the signal wire should show near 0V everytime a tooth goes past the sensor. When there is no metal in front of the sensor then the signal wire should sit at the pull-up voltage - typically about 3.8V for the internal G4X one. So all the other weird 1.5/2.0/2.5 voltages you are measuring and we are seeing on the picoscope shouldnt be there. It should be either close to 0V or close to 4V, anything else means there is something wrong with the wiring or the sensor. Quote Link to comment Share on other sites More sharing options...
merctec Posted October 3, 2022 Author Report Share Posted October 3, 2022 This I understand but what generates the voltage on the signal wire A hall sensor must rise above 1.5V and fall below 1.0V to be considered a valid edge. 1.5/2.0/2.5 are all valid then and what reads the voltage and acts on that signal I have replaced the wires and the sensor with no change in the fault changed the supply voltage source and ground location when it fails it sometimes has a voltage off 4.19v to 14.3 mv on trigger 1 and a trigger 1 and 2 signal on the runtime values and still won't give an injector or spark pulse it just so happens when I Pico scoped it had low voltage on the signal wire and why did the trigger 1 offset change after the firmware update from 348 to -12 which has now gone to -14 Quote Link to comment Share on other sites More sharing options...
Adamw Posted October 4, 2022 Report Share Posted October 4, 2022 4 hours ago, merctec said: but what generates the voltage on the signal wire The pull-up resistor, which is 3.6-4.0V depending on the sensor load. You can check this by unplugging the sensor and it will sit at the pull-up voltage. 4 hours ago, merctec said: 1.5/2.0/2.5 are all valid then No, it needs to fall below 1.0V to be valid. Yours is only going as low as 1.5/2.0/2.5 in the picoscope and the link scope suggests the same since the processed edges disappear. 4 hours ago, merctec said: when it fails it sometimes has a voltage off 4.19v to 14.3 mv on trigger 1 and a trigger 1 and 2 signal on the runtime values and still won't give an injector or spark pulse There are 3 requirements before a spark or fuel will be commanded. Firstly the ecu needs to see valid trigger 1 edges, secondly, those edges need to be received in the expected pattern (36-2 in this case), thirdly those edges must continue to be received in the correct pattern until the unique "720 sync" event is received (cam pulse). Only then the ecu has enough information to determine crank angle and cycle phase to spark at the correct time. If say just 1 trig 1 edge doesnt meet the voltage thresholds at anytime then the pattern is lost so the ecu needs to start from scratch looking for the pattern and sync event. You can look at the parameter "trigger 1 state" in the scope log to see these steps confirmed. It will show "idle" until the first valid edge is received, it will then show "blank teeth" for the first few teeth until it gets a feel for how fast the crank is accelerating, it will then show "test gap" while it is looking for the gap, once its seen something it things looks like a gap it will say "verify gap", if the gap meets the requirements (ie 2 missing teeth), then it will say "counting". It will then count 34 teeth and change to "tooth before gap", then tooth after gap, then back to counting and repeat. If an incorrect pattern is received then the status will revert to idle or blank teeth and start from scratch. Crank position has been determined when the status first changes to "counting" and provided trigger 2 hasnt contradicted that position the spark will be commanded on the very next cylinder to reach TDC after that point. You will see dwell commanded in the log as further confirmation. I think I told you to change the sync tooth to 1 in one of the other threads so this cant happen. 5 hours ago, merctec said: and why did the trigger 1 offset change after the firmware update from 348 to -12 That is a difference of 360deg. ie the ecu had the crank position but cam/phase position was moving. This was due to your sync tooth originally being set to 14 but with the sync tooth occurring right above tooth 14. So depending on any slight cam movement due to temperature, drive backlash etc it could cause it to sync on the wrong crank rotation sometimes. It is not related to firmware. Quote Link to comment Share on other sites More sharing options...
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