Immobiliser with keypad on XUD

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Re: Immobiliser with keypad on XUD

Post by wennbom »

I have ordered a new sensor.
The one on the car measures 100 Ohm

Are these sensors passive units?
Measuring the harness side with engine running I have 0 volts.
I have traced the wires back to their sources
Black - GND
Red - goes to "SENAL RPM" rpm signal
Grey Yellow - goes to?
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white exec
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Re: Immobiliser with keypad on XUD

Post by white exec »

100R sounds about right. I think the one here (also XUD9) was 71R.
Sensor is passive, and not powered.
It generates a tiny tiny impulse voltage each rotation of the flywheel.

Tip needs to be 1mm from the flywheel periphery; new ones have a small plastic spigot on the end, which should be fitted actually touching the flywheel. This decapitates itself as soon as the engine is started, leaving the required 1mm gap.

Cable to the sensor is uaually 2-core + a screen. Screen should be grounded, at one end or the other. Oddly, on ours, the 2+screen cable leading away from the sensor gave way to a 2-way connector about 0.5m away.

Important to get the correct sensor. IIRC the diesel sensors are different from some petrol ones.