Hi guys welcome back
In this video we are going to be using out PicoScope to
To test a cam crank correlation
And what that means is that we will be looking at the cam sensor
And the crank sensor together on the same screen
That is pretty handy if you have a suspicion
That you may have a timing issue on your vehicle
And this is a good way to verify that
The sensors on this vehicle are VRS valve sensors
Variable reluctance sensor
They both generate an AC sine wave we have videos on both of those
So be sure to look in the description bellow for those independent component tests there
I am going to show you the hook up and get the scope fired up and show you how to do this
We will go up here to the automotive tab and go to the advance test menu
Then cam and crank sensors
That will open up a web browser to read
There are a couple of different ways to do this test depending on the sensors
So we will hook channel A to our crankshaft sensor
And channel B to our camshaft sensor
We have got channel B over here
The cam sensor is easy to get to on this engine right on top of the valve cover
We have gone ahead and back probed it
As mentioned in the inductive cam sensor video
If you do not at first get a signal on one of the wires
Go ahead and switch to the other wire and see if your signal is there
One of these wires will be signal return
One of them will be return to ground
On this vehicle I am hooked into the crankshaft sensor using the TA012 adaptor that Pico makes
So you can just unplug the sensor
This is a jumper harness that is going to give us two banana jacks
Be mindful of the belt you do not want to be getting these wires tangled up in the belt
I have gone ahead and probed one side of that crank signal
They are going to make a mirror image of each other so
It is not 100% necessary which one you grab
Unless you are comparing it to a know good
A lot of people like to use the main signal as opposed to the sub signal
And then I have both grounds hooked to the battery negative
Here is a picture of that TA012 connector that we will be using on this vehicle
If you are curious about that
We will go back to our scope there is a sample waveform already there for us
We will hit the space bar to get this rolling and start the car up
ENGINE STARTS
We will stop that and shut the car off
Just be sure that if you are gathering this for a cam crank correlation comparison
We will slow this down a bit and get a bigger capture
Now we will stop that there
That is a fantastic looking wave form
There is a little bit of noise there on the cam signal
That is easy enough to clean up by adding a little bit of filtering to that
That is way too much
That looks good now
We can zoom right in on this baby
We have captured it on a little bit longer time basis
So we can zoom out on that a little bit
And see how the cam signal is in relationship to the crank signal
If you suspect you have a timing issue
This is the test you are going to want to use
As I have mentioned in other videos
Always save your waveforms you never know when you are going to need them
we are going to select our vehicle and add in our channel notes
Then click save and share so we can add it to the Pico library
Alight guys that is it a simple test to do
It is a very valuable test to do particularly if you suspect there is a cam
Crank correlation problem for example
Has the timing belt slipped has the timing chain slipped
What is going on there if you have this waveform
If you have a known good waveform to compare your car to you can
Make a definitive answer make the call
And never get your hands dirty
So that is it guys thanks for watching