Scope for auto diagnosis

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Was watching South Main Auto video where Eric used a 4 channel oscilloscope to diagnose a Ford with smart charge system. He spent time to understand how the system works and to diagnose with both a scope and scan tool. So my question is does the average Indy shop have a scope and do they take to time to diagnose problems with a scope. Eric seemed to have an expensive Pico scope adapter that turns a laptop into a scope. Not a $100 cheapie. But one needs the scope and knowledge to use it. It's a lot more knowledge required to use a scope than take a DVM and measure battery voltage.
 
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Would an average person know how to interpret the squiggly lines on an EKG? Not likely. Pretty much the same with a scope. You need experience to tell what's normal and what isn't.
 
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My Fluke 98 used to go on every car that came into the shop...that's how you learn. Now it sits in a draw and never comes out, the scanner does it all these days.
 
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The picoscope is, well, kind of expensive for a normal oscilloscope but most auto techs buy them. They have a good library. You can download the software and run it in simulation mode on your computer for free, before you buy. Trust me, it's the exact same software. Problem is, once you come to a point where you need to see an AC signal, you don't have a choice, you must use an oscilloscope. At that point, with Picoscope the choice is 2 channel or 4 channel. Seems the lifetime is pretty long with these, kind of an industry standard, and they don't nickle and dollar you to death for updates. In Eric's earlier videos he explained most of the time you can get away with what a scan tool tells you, but sometimes you need to see the same input the car's computer sees (and he'd emphasize when you'd need the oscilloscope).
 

Donald

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Is there something unique about a Pico scope or does it just make a laptop function as a scope? Would a 2 or 4 channel Tektronix do the same as a Pico scope?
 
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You could probably do most work with a Tektronix, though my knowledge of those are the old analog versions. Using a Picoscope is not like using an analog scope. I know a lot of signal processing has to occur at the box; the PC/laptop is just a processed signal display. You'll likely miss the signal in real-time; scroll back and zoom to look at an event. (Whereas with an analog scope you either see the event in real-time.) You likely have a higher Vmax with the Pico (+/-100V). USB3 powers the Picoscope, so that's nice. No extra power supply. It also does some bus decoding.
 

Donald

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Originally Posted by spackard
You could probably do most work with a Tektronix, though my knowledge of those are the old analog versions. Using a Picoscope is not like using an analog scope. I know a lot of signal processing has to occur at the box; the PC/laptop is just a processed signal display. You'll likely miss the signal in real-time; scroll back and zoom to look at an event. (Whereas with an analog scope you either see the event in real-time.) You likely have a higher Vmax with the Pico (+/-100V). USB3 powers the Picoscope, so that's nice. No extra power supply. It also does some bus decoding.
The cost of the Pico scope rules it out for most shade tree mechanics. Is there anything for the shade tree mechanic who understands the basics of using a scope?
 
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Originally Posted by Donald
Was watching South Main Auto video where Eric used a 4 channel oscilloscope to diagnose a Ford with smart charge system. He spent time to understand how the system works and to diagnose with both a scope and scan tool. So my question is does the average Indy shop have a scope and do they take to time to diagnose problems with a scope. Eric seemed to have an expensive Pico scope adapter that turns a laptop into a scope. Not a $100 cheapie. But one needs the scope and knowledge to use it. It's a lot more knowledge required to use a scope than take a DVM and measure battery voltage.
Honestly......Not many mechanics know how to use a scope! A lot of manufacturers write their diagnostic information-Trouble Tree's right around the use of a scope! They will have you ohming wires & sampling voltages for hours in a process of elimination...........Toyota being a major exception, They encourage the use of a scope! I have a Snap-on Vantage Pro, It's not nearly as capable nor does it have the resolution of a "top of the line" 4 channel Pico! But it does everything I need it to do on a professional level. Though I do wish I had more than 2 channels at times.
 
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Originally Posted by clinebarger
Originally Posted by Donald
Was watching South Main Auto video where Eric used a 4 channel oscilloscope to diagnose a Ford with smart charge system. He spent time to understand how the system works and to diagnose with both a scope and scan tool. So my question is does the average Indy shop have a scope and do they take to time to diagnose problems with a scope. Eric seemed to have an expensive Pico scope adapter that turns a laptop into a scope. Not a $100 cheapie. But one needs the scope and knowledge to use it. It's a lot more knowledge required to use a scope than take a DVM and measure battery voltage.
Honestly......Not many mechanics know how to use a scope! A lot of manufacturers write their diagnostic information-Trouble Tree's right around the use of a scope! They will have you ohming wires & sampling voltages for hours in a process of elimination...........Toyota being a major exception, They encourage the use of a scope! I have a Snap-on Vantage Pro, It's not nearly as capable nor does it have the resolution of a "top of the line" 4 channel Pico! But it does everything I need it to do on a professional level. Though I do wish I had more than 2 channels at times.
True, they didn't teach that in trade school (that was a long time ago for me I don't know about today), I learned how to use one in a manufacturers school.
 
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I've been wanting to buy my own Picoscope, I've been wanting to play more with electronics at home and a good scope would be a must. Although when I use one at work I often find only 4 channels limiting. Still. I do like Pico's when debugging stuff at my desk. For auto work, I've been tempted to buy one of the cheapo things on Ebay. There's a bunch of cheapo single channels one there, which IMO are not much more than a graphing DMM--but that is probably all that is needed for some of the debug work (not debugging CAN or the like, but a simple PWM or O2 sensor? probably good enough). Now that I look I see the price has come down again.
 
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Supton - There's a seller on EBay that has two used (says look unused) Agilent U1602B Handheld Digital Oscilloscopes for sale, for $199 each. You'd have to spend more for probes, charger, maybe a current clamp. Thing is - whenever I asked an EE about buying a 'scope they always asked me 'what is it you want to measure?'. I didn't have a good answer (I buy test equipment first because I am curious, later finding a real use for it most of the time.) So I lived decades without one, and I can do a lot without one. I suggest you ask yourself the same question, as when you have the answer then the answer drives what type of 'scope you need. My Picoscope I bought this year, having finally answered the question and having no other indirect method I could use. Measuring and comparing the raw signals of two knock sensors, so I could see what the computer was seeing.
 

Donald

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Originally Posted by spackard
Supton - There's a seller on EBay that has two used (says look unused) Agilent U1602B Handheld Digital Oscilloscopes for sale, for $199 each. You'd have to spend more for probes, charger, maybe a current clamp. Thing is - whenever I asked an EE about buying a 'scope they always asked me 'what is it you want to measure?'. I didn't have a good answer (I buy test equipment first because I am curious, later finding a real use for it most of the time.) So I lived decades without one, and I can do a lot without one. I suggest you ask yourself the same question, as when you have the answer then the answer drives what type of 'scope you need. My Picoscope I bought this year, having finally answered the question and having no other indirect method I could use. Measuring and comparing the raw signals of two knock sensors, so I could see what the computer was seeing.
He had two but now only one. $299 plus shipping. The U1602B is a 2014 year scope.
 
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If you are on a budget, go on ebay and get a snap on vantage pro. Very powerful tool in the right hands.
 
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What did you choose in the end? Can you tell us more about your choice? I'm thinking about buying a second diagnostic device now, but I don't know what to choose. My main device is a diagnostic device from thinkdiag.co.uk and I am completely happy with it, but some of my colleagues say that there is a possibility that the error will be incorrectly determined. I've never experienced this before, but now my paranoia won't let me calm down. For some reason, it seems to me that this device can incorrectly detect an error, so I decided to buy another one in order to avoid such a problem. Thank you in advance for your answer.
 
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