Vauxhall Vectra B facelift (1999 - 2002) - 99 2.0 How to test cam sensor?

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Sun 12 Apr 2009 12:21
99 2.0 How to test cam sensor? - kpm197
hi, i'm getting zero volts readings from my cam sensor with ignition on. i have a brown/green, grey/red and grey/black wire, and a screening shield. ive tested all variations of the wires but im getting no reading. i also put the black multimeter probe on negative battery and tried positive probe on all three wires, expecting that at least one of them would give me 12v, but no go. am i doing something wrong? multimeter is set to one of the V readings which gives me 12v from the battery.

should i be using ohms?

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Sun 12 Apr 2009 12:40
99 2.0 How to test cam sensor? - kpm197
the grey/red is the oscillation signal to the sensor so i assume 12v and the grey/black is the signal from the sensor so i assume so i assume a fluctuating 5v? brown/green is brown.
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Sun 12 Apr 2009 12:59
99 2.0 How to test cam sensor? - Hamsafar
Does the sensor need 12v? I wouldn't have thought so. I would expect it to be passive.
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Sun 12 Apr 2009 13:04
99 2.0 How to test cam sensor? - bell boy
check the ohms between pins 1 and 3 on the senser it should read 11 to 15 ohms
pins 2 and 3 as you lok at it face on with the bump for the connecter upwards should read 11 to 15 ohms
these figures approx
stop back probing the wires to the ecu

why not just buy a new senser with the lead attached as if i remember correctly it was the lead picking up interferance from other consumables rather than a faulty senser (they coaxed it i believe)
sorry not a vectra man
so i could be wrong

Edited by bell boy on 12/04/2009 at 13:05

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Sun 12 Apr 2009 21:07
99 2.0 How to test cam sensor? - kpm197
hi, thanks, i get 12.3 and 12.8 ohms so within range. you mention about not back probing the wires on the ecu end, is there anyway i can check continuity in these three wires? i have an eml code 0340 for cam sensor, although it wouldnt surprise me if this is a red herring.

the engine has already had the updated sensor & loom.

edit: you are correct with the sensor, they put a faraday cage on there to protect from inteference.

Edited by kpm197 on 12/04/2009 at 21:08

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Sun 12 Apr 2009 22:31
99 2.0 How to test cam sensor? - SpamCan61 {P}
I've checked the continuity in the past by disconnecting the ECU ( after disconnecting the battery first) and then checking at the end of the loom that connects to the ECU. Beware, there are a lot of pins in there to count!
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Mon 13 Apr 2009 20:44
99 2.0 How to test cam sensor? - kpm197
hi, i checked continuity at ecu and it was a couple of tenths under the reading at the sensor but still within range. i even went one further and removed the three pins from the ecu and tested these with the engine running to see if i got any inteference but good ohm readings so im stumped why i still have a fault code.
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