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VW Touran with BLS engine-code to work on.
Car stores a faul-code for the G28 crankshaft-position-sensor and the car intermittent stutters when it takes a bend / turn.
My idea was to test the cables going to the crankshaft postion sensor.
The problem is:
It´s almost unpossible to unplug the sensor and test voltage + ground directly at the sensor, because it lives behind the oil-cooler in a pocket of the engineblock. My question:
Would it be possible to messure a voltage directly at the connected plug of the enginge computer, at the negative lead, if the sensing wheel at the crankshaft is in a defined position + ignition on? OR
Possible to get voltage at the signal wire when the enginge not runs, ignition on (plug connected to the engine computer) if the sensing wheel at the crankshaft is in a matching position???
I never did such messurements before, because it was always possible to take messurements directly
at the sensor.
In general speaking (i don´t know exactly this one), you can backprobe at PCM connector signal wire.
If you have a scopemeter, you can watch voltage falling and rissing in a square waveform with engine running. With a multimeter, you can see an average voltage with a value between ground and VCC.
You can also watch voltage rissing(VCC) and falling (0V) with key on engine off and spinning slowly the crankshaft.
Bear in mind that this test is not 100% accurate. This test doesn´t stress the sensor (you are not simulating different temps, speeds, interferences). If you check wiring/connector integrity, reluctance Wheel integrity, clear the code, check that sensor is switching as described and code pop up again, you should replace it.
Thanks for answering. I know that I can check the signal coming from the sensor via scope. The question I have is, if it's possible to see voltage on the negative lead back at the engine computer connector. My thought is that the hall element leads voltage through if the sensing wheel is in a defined position?
Yes, you can check crankshaft signal at the pcm connector. In some cases it's the better spot to test from to be sure the signal is making it back to the module.
