Crank Sensor Polarity....

Discuss which Sensors work best with these ECUs and share how you are using inputs and outputs
Post Reply
SeniorGT
Posts: 19
Joined: Mon Oct 24, 2011 5:44 pm

Crank Sensor Polarity....

Post by SeniorGT »

Right guys, bit of a head scratcher. Ive got to throw this out there as its confused me for the last few days.

Basically over a year ago i took my Citroen c2 off the road for a few weeks to do a few repairs, and fit some new parts. At that time it had been running on a P8 for well over 6 months without any issues. I changed quite a few parts but the main thing of importance is the clutch, nothing was fitted that affected the DTA either.

When all was done i came to fire the car up to find it wouldnt start, went through all the usual tests, everything was working fine, in fact i thought to myself the symptoms it was displaying screamed that the c/s was wired the wrong way, but i foolishly dismissed it, as it had been fine before it came off the road. After a couple of more days i thought sod it ill swap the pins on the c/s plug, and hey presto it fired straight up. I scratched my head for a few days over it but in the end thought it didnt matter and was a freak occurance.

Untill the other day when we did a clutch on a turbo'd saxo weve built, and it happened again, this time on a S40 that had been on the car for 2 months. didnt change the c/s, same flywheel, no other work done other than the clutch itself.
Spotted it as soon as i ran a crank scope test, so a much quicker fix than last time.

So my question is...... what the hell could cause it??

Cheers, James.
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Crank Sensor Polarity....

Post by stevieturbo »

Both French cars.....they're renowned for wonderful wiring lol

But aside from that, cant really understand how such a problem could ever occur.
SeniorGT
Posts: 19
Joined: Mon Oct 24, 2011 5:44 pm

Re: Crank Sensor Polarity....

Post by SeniorGT »

stevieturbo wrote:Both French cars.....they're renowned for wonderful wiring lol

I had that coming, lol.
Like youve said though, i cant understand how or why theyve done it.
welshpug
Posts: 130
Joined: Tue Sep 06, 2011 4:53 am
ECU Model: S40 Pro

Re: Crank Sensor Polarity....

Post by welshpug »

french cars with german components :p

2 wre or 3 wire sensors?
huwjones
Posts: 5
Joined: Tue Feb 07, 2012 3:41 am
ECU Model: S40 Pro

Re: Crank Sensor Polarity....

Post by huwjones »

Did you change the clutches for exactly the same ones?

The only thing I can think of is that the new clutches are having an affect on the 'background' magnetism. I'd be surprised if they made that much difference though...
SeniorGT
Posts: 19
Joined: Mon Oct 24, 2011 5:44 pm

Re: Crank Sensor Polarity....

Post by SeniorGT »

Theyre both on 2 wire sensors, One clutch was changed for a valeo direct replacement and the other had a cerametallic paddle clutch fitted.

Spoke to a few people over the last few days, got nothing but odd looks. lol
Post Reply