@ADPTraining I'm a 21 year telecommunication technician and light to medium AC electrician, but I'm referring back to school to obtain my EE, I will keep you in mind, and love the Tech talk I can't get enough!
Again, good question. This is a horrible design mistake made by some equipment makers. The best explanation I can give you is this: Years ago when installing a car radio some speakers had what was called FLOATING GROUND. This means that the vehicle ground is different than the speaker ground. The same goes for some magnetic sensors. And at any point in time this may hold true for any future sensors ground or network return line (ground).
@ADPTraining CONTINUED: The importance of all this is that the ECM needs a specific P-to-P value to be able to recognize the signal. Signal recognition threshold is an often ignored point when it comes to diagnosing signal issues. I appreciate your input and keep it up. We also have a new BMW and Advanced Electronics SERIES here on this channel. Enjoy...
To determine if your scope lead ground is vehicle ground just do a continuity test (using a MM) from Batt ground to the Black lead. Remember to power up whatever scope you're using. Often times on grounded units it may be necessary to run the scope on battery alone to isolate the equipment and be able to graph floating ground Magnetic speed sensors.
@James1toknow Hello, well not always. On most systems the sensor ground is not isolated. On some rare systems they use a floating ground, but this practice is pretty much gone. I should mention that the Hall-Effect does not produce a sine wave. It produces a square wave. The side wave seen here is from a magnetic crank sensor. The HE sensor contains its own switching transistor. Thanks so much for posting and good luck.
@sissifranca Thanks for the compliment. Ok I understand your point, but in reality there are various ways to view this issue. First, (not in this case) the entire waveform could be above the zero line and PP would still be the same. As a rule, you're right, peak value in zero to either positive or negative maximums. The reality is that unless you have a clipping diode in the circuit (doesn't apply to cars), both sides would be that same. CONTINUED:::
@ADPTraining Great I don't have a problem but note on another instruction said that the hall effects do produce a sine wave or ac current but I have noted what you said and will remember this. thank you.
I just want you to ask if you know how to acquire a data base. or maybe a personal list or how to make with Oscilloscope a Synchronized CKP+CMP signal.
thanks! i recently put in a NEW (but bad) CKP sensor and its apparently shorted internally- screwing up my fuel level gauge, ignition coil/ignitor(?) and setting off a host of other selonoids- et al! I cleaned all grounds, rebuilt my fuse box, new ECU, cleaned everything........no changes UNTIL i just now decided to swap back in the old CKP sensor. All the electrical clicking, etc went away immediately and Im not going thru the KEY RELEARN process for the new ECU
@@ADPTraining much thanks! Im trying the key relearn now today- since I put in a new ECU......ill let you know how it goes. my email is atomicdmt1111@yahoo.com
@srdmagic Nice of you to post. I'd to coax a bit more information off of you and like you to tell us what we've done right and why you like or don't like about our videos. We also encourage you to visit our latest series "Stories from the Road", "BMW European technology" and "Advanced Automotive Electronics". Thanks so much for posting.
Does spycrow lye feel that, if there is inadequate or zero fuel pressure, for example, on a Common Rail Diesel, would you still use the same method? Many thanks, Joe
They either work or they don't, in my experience. If the injectors are switching the Crank PS is working. I listen to the injectors to diagnose crank sensors.
