Ask for and share advice on using the PicoScope kit to fix vehicles here.
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Fat Freddy
- TwoWaves
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by Fat Freddy » Sun Nov 11, 2012 8:55 am
I hold my hands up on this one as I don't know how to set the scope up to measure Hz?
On the tool bar you have your channel. Beside that you can select the range you want and beside that is your selected coupling. You will find it here. You have the choice of AC or DC coupling or Frequency. I think the scope has to be plugged in to have this option. And only one channel at a time may use this option.
See "Coupling control" in the users guide.
Regarding the examples given by AD. Personally I find them a poor representation. For example the 2000 Jeep Wrangler IAC has me baffled. Although I may be misunderstanding the image. 
EDIT: I suspect it's a differential measurement across the two pins.
HTH
FF
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djmikeyboy
- OneWave
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by djmikeyboy » Mon Nov 12, 2012 3:24 pm
Ok I've taken some amp readings now, for some reason today with everything back together my position sensor signal is about right at idle (still will not move though).
I have taken amp readings from BM2 AND BL2 to be sure.
Current channel A (blue) BL2
BM2 (red)
BD2 (green)
- amp BL2 running.psdata
- Current readings from BL2 engine running,blipped, held at various rev ranges, sharp on off etc
- (78.73 KiB) Downloaded 276 times
Current A BM2
BL2 (red)
BD2 (green)
Hopefully this may shed some more light on things.
Freddy I agree with you about trusting all AD figures. Have been caught out in the past, hence coming on here to talk to the experts!
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Robski
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by Robski » Mon Nov 12, 2012 8:19 pm
Hopefully this may shed some more light on things.
NOPE.
Take 3X channels on BM2/BL2/BD2, attach current clamp to either BM2/BL2 (correct polarity) & take a capture at engine off.
Then either blip the throttle watching the same channels or take for a road test through different load ranges of the engine, plenty of time on screen + sample rate & post the 2X captures, then we may get a good idea of what is going on.
I'm out ...........
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djmikeyboy
- OneWave
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by djmikeyboy » Mon Nov 12, 2012 9:52 pm
oh, thought that's what I'd done? Right then, I'll have to go back to my origional plan of sending the ECU away for testing. Will at least rule it out if it tests ok. THANK YOU for trying to help a Pico Newbie out. I've still learnt alot even if I haven't fixed it yet.
Mike
Will post again if I get to the bottom of it!
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Robski
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by Robski » Mon Nov 12, 2012 10:10 pm
you said "although it will cycle fully when the engine has been running for a few minutes and is switched off. "
So I asked "Take 3X channels on BM2/BL2/BD2, attach current clamp to either BM2/BL2 (correct polarity) & take a capture at engine off "
And also suggested "Then either blip the throttle watching the same channels or take for a road test through different load ranges of the engine, plenty of time on screen + sample rate & post the 2X captures, then we may get a good idea of what is going on.
You don't appear to have done this 
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Darren Cotton
- TwoWaves
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by Darren Cotton » Mon Nov 12, 2012 10:13 pm
djmikeyboy wrote: I'll have to go back to my origional plan of sending the ECU away for testing. Will at least rule it out if it tests ok.
What is the point in that!!! You have the best test rig right in front of you......
Darren
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Robski
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by Robski » Mon Nov 12, 2012 10:17 pm
Darren Cotton wrote:djmikeyboy wrote: I'll have to go back to my origional plan of sending the ECU away for testing. Will at least rule it out if it tests ok.
What is the point in that!!!
You have the best test rig right in front of you......
Darren
ABSOLUTELY ........ the best test bed is the car it's self 
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djmikeyboy
- OneWave
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by djmikeyboy » Mon Nov 12, 2012 10:59 pm
Oh.. capture when I TURN the engine off! Thought you meant WITH the engine off, hence a capture with the ignition on. sorry.
The second captures were with the engine running blipping the throttle and trying different rev bands.
I will try again tomorrow and do a proper road test and the switching off capturing now that I'm clear about that. Have I misunderstood the other capture you wanted as well?
Your patience is appreciated. I would of course like to solve this with the Pico now I've bought it, that's the whole point.. Just need a lot of practice and help.
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djmikeyboy
- OneWave
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by djmikeyboy » Tue Nov 13, 2012 11:59 am
Ok this car is out to make me look an even bigger fool than I've been doing myself up until now.
Set the scope up this morning to capture the switch off cycling only to find that it isn't doing it anymore!
Originally with the motor disconnected from the mechanical valve part I could watch it cycle 4 or 5 times when the engine was switched off. I have taken it off again this morning,after not hearing it move and tried both the original and the second hand one again, neither is moving at all.
Needless to say there is no current detected in the wire so I didn't see the point of posting that capture or going for a test drive.
I tried to actuate the valve with the Launch but nothing happened/no current detected.
I have noticed that the fault code is returning much quicker than it was before.
I will cautiously say at this point that I am still suspecting a dry joint inside the ECU
But I will probably get some "constuctive" Criticism for that theory. It's greatly appreciated none the less.
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djmikeyboy
- OneWave
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by djmikeyboy » Tue Dec 04, 2012 9:52 pm
For anyone still interested... and because I hate reading unsolved cases, got it fixed with a software update! Which is a bit surprising as I took this job on after the local Ford dealer couldn't fix it, ended up finding out about the update through another friend in the trade who had the Ford IDS tool.
So I guess it's not what you know, and it's not who you know, it's what who you know knows! 
