Keith Spencer
Member
Watch the "mechanic mindset" on YouTube he creates all the faults and shows you the results on the oscilloscope, very educational.
Technical Canbus low, pin 14 battery voltage problem
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Technical Canbus low, pin 14 battery voltage problem
Keith Spencer
Member
Remember that all an oscilloscope is, is a dvm but ultra rapid reading and the visual display screen to provide the readout. If you can use a dvm then an oscilloscope is a piece of cake.
Communicator
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In my younger days, getting the correct trigger/sync setting was part of the exercise. DVMs did not need that.
Keith Spencer
Member
Hi communicator,
Nowadays it's automatic and not so difficult to set the trigger, you can do it on manual if you prefer.
Nowadays it's automatic and not so difficult to set the trigger, you can do it on manual if you prefer.
Go to new posts on top left, then click on post threads in yellow on top right.
Keith Spencer
Member
Hi Everyone,
Latest update is:-
I have received the 3000+ page 250 Mb workshop manual and the wiring diagrams have a totally separate booklet for the weird symbols, the numbers and lettering used. I have everything but it's going to take a long time to work through.
One good thing that came out of it is that I can see how the Obd2 socket is wired for high and low speed networks as follows :-
Pin 6 = Can Hi, Low Speed
Pin 14 = Can low, Low Speed
Pin 2 = Can Hi, High Speed
Pin 10 = Can Low, High Speed
As a result I have now been able to test both networks and see that all looks healthy. But my xtool scanner is doing some odd things and showing unable to read the vehicle as a fiat, but if I manually scan it as a peugeot boxer or Citroën jumper it provides me with most live data and some actuation testing and DTC code reading/reset. I have been discusseing with xtool and they assure me that they will be updating the scanner for me by the end of July.
I still have the high voltage on pin 14 when asleep, but all others are now reassuringly normal and the vehicle has no operational issues.
So it's probably time to move on after a steep learning curve, just got to learn the Italian /French wiring diagram protocol /philosophy now. A BIGGER CHALLENGE BY Far
Thanks for all your comments.
Latest update is:-
I have received the 3000+ page 250 Mb workshop manual and the wiring diagrams have a totally separate booklet for the weird symbols, the numbers and lettering used. I have everything but it's going to take a long time to work through.
One good thing that came out of it is that I can see how the Obd2 socket is wired for high and low speed networks as follows :-
Pin 6 = Can Hi, Low Speed
Pin 14 = Can low, Low Speed
Pin 2 = Can Hi, High Speed
Pin 10 = Can Low, High Speed
As a result I have now been able to test both networks and see that all looks healthy. But my xtool scanner is doing some odd things and showing unable to read the vehicle as a fiat, but if I manually scan it as a peugeot boxer or Citroën jumper it provides me with most live data and some actuation testing and DTC code reading/reset. I have been discusseing with xtool and they assure me that they will be updating the scanner for me by the end of July.
I still have the high voltage on pin 14 when asleep, but all others are now reassuringly normal and the vehicle has no operational issues.
So it's probably time to move on after a steep learning curve, just got to learn the Italian /French wiring diagram protocol /philosophy now. A BIGGER CHALLENGE BY Far
Thanks for all your comments.
theoneandonly
Established member
As a result of
I decided to buy the Pico 2204A and the Hantek probes. Best software (also lots of help) and cheapest ancilaries. Just have to wait 2 weeks for voltage probes and attenuators to save £z
My main requirement is for injector assessment. I will start a new thread when ready. By the way i'm a mere youngster at 68
Keith Spencer
Member
PS,
I checked the end resistors on pin 2/10 and voila 60 Ohms, perfect. So I am assuming that the 48 Ohms is correct on the slow speed. Did a little forum search elsewhere and found someone else with the same readings as me. So all is good, just got to get xtool to update their ducato software. Thank you all.
I checked the end resistors on pin 2/10 and voila 60 Ohms, perfect. So I am assuming that the 48 Ohms is correct on the slow speed. Did a little forum search elsewhere and found someone else with the same readings as me. So all is good, just got to get xtool to update their ducato software. Thank you all.
SmiffDaMista
Member
Thankyou mate , got the matrix in and the dash allback together , but still need mass air flow sorting i think, cuts out once it warms up and wont restart untill its cooled down , what do you think please
Keith Spencer
Member
Hi smiff
If you think it's a maf issue (what DTC's are you getting after shutdown) I would put the maf on live data in a scan tool and graph it. Then watch from cold until shutdown and see if anything changes.
Are you getting a sensible g/s reading on the maf? If nothing changes forget the maf and look elsewhere.
When you try to restart the engine is the rev counter moving slightly?
Failure when hot suggests an expansion of something that causes the issue, I would try a wiggle test, whilst cold and running, see if you can reproduce the fault early. By wiggling various harnesses and components around the engine.
Is anything else happening at the same time that is unusual?
I would put an oscilloscope on the obd and check the signal from cold to failure. This may indicate if the ECU is responsible or it could just be a mechanical issue.
Difficult to diagnose without being with the vehicle.
Keep me posted Smiff.
What vehicle /engine is it?
If you think it's a maf issue (what DTC's are you getting after shutdown) I would put the maf on live data in a scan tool and graph it. Then watch from cold until shutdown and see if anything changes.
Are you getting a sensible g/s reading on the maf? If nothing changes forget the maf and look elsewhere.
When you try to restart the engine is the rev counter moving slightly?
Failure when hot suggests an expansion of something that causes the issue, I would try a wiggle test, whilst cold and running, see if you can reproduce the fault early. By wiggling various harnesses and components around the engine.
Is anything else happening at the same time that is unusual?
I would put an oscilloscope on the obd and check the signal from cold to failure. This may indicate if the ECU is responsible or it could just be a mechanical issue.
Difficult to diagnose without being with the vehicle.
Keep me posted Smiff.
What vehicle /engine is it?
Keith Spencer
Member
Check above for my replyThankyou mate , got the matrix in and the dash allback together , but still need mass air flow sorting i think, cuts out once it warms up and wont restart untill its cooled down , what do you think please
May be totally wrong and also not indicated by your error codes, but the symptom of cutting out when hot, then restarting as cools down was what I had on my 05 Doblo1.9 and it was the Crankshaft Position Sensor as I mentioned much early in the thread about another point.Thankyou mate , got the matrix in and the dash allback together , but still need mass air flow sorting i think, cuts out once it warms up and wont restart untill its cooled down , what do you think please
Keith Spencer
Member
Hi Smiff,Thankyou mate , got the matrix in and the dash allback together , but still need mass air flow sorting i think, cuts out once it warms up and wont restart untill its cooled down , what do you think please
Most people fall into the trap of going for the MAF because it is easy to access. If you still think it is the MAF, an easy test I forgot to mention previously is to unplug the MAF whilst the engine is cold and running. Most engines with the MAF disconnected will run, but badly that will show you if the engine is cutting out because of the MAF. If it does cut out which I doubt, then you can attach the scanner and do as I said with the live data plotting the graph and watching it While it cuts out. The normal flow at tickover should be between four to 10 grams per second depending on your engine size.
Don't do what most people do and start firing the parts cannon and if you are tempted to buy a part that you haven't proven is faulty then be much wiser and spend the money on a decent scanner I use the X tool D7 or even a D8 which is about 300 pounds. Sorry for this late advice but I'm getting old and need a cup of tea thinking time lol.
