Help with crank sensor signal

Bazgreener · Post by **Bazgreener** » Tue Aug 10, 2021 6:06 pm

Hi all,
not had my pico long and trying to start using it more as it's an expensive doorstop

I have a 2006 caddy van with a 1.9TDi which isn't seeing a crank sensor signal, the engine will start after prolonged cranking but is showing a crank sensor fault code and also the torsion value shows 0deg and rev counter not working. I have checked the wiring from the ecu down to the sensor and i have continuity on all three wires. I have a black/red with 5v which i assume is the supply and also a purple wire and a brown/blue. As the sensor plug is inaccessible i have back probed the ecu plug but i'm not really understanding the waveforms i am seeing.
The first image is from the purple wire which i originally used the guided test settings but it was showing voltage out of range so i had to adjust to 100v
The second image is the brown blue wire.

thanks in advance
Barrie

liviu2004 · Post by **liviu2004** » Tue Aug 10, 2021 8:32 pm

Sure aren’t some plugs mixed up? Like with a knock sensor or something?

ronw38 · Post by **ronw38** » Tue Aug 10, 2021 9:08 pm

Looks like the purple wire is an injector or solenoid control; wrong hook up? Cheers Ron W

Bazgreener · Post by **Bazgreener** » Wed Aug 11, 2021 5:52 pm

Not sure what happened with the last waveforms as after i restarted my laptop it gave a completely different waveform.
What are your thoughts on this?
It's a hall sensor so should be switching between 0v & 5v?

thanks

ronw38 · Post by **ronw38** » Wed Aug 11, 2021 8:53 pm

That could be an earth signal, if it is the crank sensor signal wire the sensor is faulty? you should be seeing a 5v square wave a clean sharp edged digital signal. Cheers Ron W

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