Jump to content
Fraser

Renault trigger signal/polarity issue (now resolved)

Recommended Posts

Can someone confirm that the attached trigger trace is the WRONG polarity?

It goes negative as the tooth approaches which would tell me it's wrong, but if i swap the 2 cores over, it wont start at all.

Is there a way in software to invert it or can anyone explain why it wont fire when its physically swapped?

Sensor is an OE Renault crank sensor and plug.

 

Fraser

trigger.PNG

Share this post


Link to post
Share on other sites

Your crank sensor is definitely incorrect polarity in your scope.  After swapping wires check that there is RPM displayed during cranking.  If there is then as per Cam's comment it is likely just the offset needs calibrating.

If no RPM displayed after swapping wires then give us another scope capture.

Share this post


Link to post
Share on other sites

Gents, thanks for the feedback.

sorry for the delayed reply. Flat battery, frosty weather, kids...etc...

 

just having a go just now. swapped the wires on the pickup and no RPM sig and no noticeable trigger on the pclink scope.

dropped the arming threshold as low as i could and got it to register on the scope - showing a now correct polarity (attached). but i still see no RPM sig.

this is a fully charged battery running at normal crank speed.

for some reason there is a marked loss of power generated from the pickup when the wires are inverted. 

 

what to do now?

cheers,

Fraser

trig wires inverted.PNG

Share this post


Link to post
Share on other sites

What do you have for a cam trigger?

If there is no cam trigger then in you trig 2 settings make sure the sync mode is set as none. 

I'm assuming the ECU has been unlocked also?

 

Share this post


Link to post
Share on other sites

Simon. 

No cam trig used.

Engine ran great for months apart from a wandering idle which i was puting down to the inverted crank signal causing the ecu not trigger on the right edge.

Since ive tried to get it to run 'right' ive ran into these problems.

If i swap it back, it runs fine.

 

Cheers

Fraser

Share this post


Link to post
Share on other sites

Your trigger scope images above do not match the Renualt Clio expected pattern.  With the sensor wired backwards the ECU would see an extra "edge" which would make it a closer match thats why it works when it is connected backwards.

The Renualt Clio has an odd 60 tooth arrangement, with 1 long tooth then 1 missing tooth.  Yours looks like a normal 60-2.

Heres a clio:

295zfol.png

 

Try the attached file, I have changed it to generic 60-2.  You will need to check trigger offset with a timing light but I suspect it will be close enough to start.

281643309_reallygoodkangoo new trigger setup.pclr

Share this post


Link to post
Share on other sites

Adam,

I followed the help note in the Link manual which advised i had to machine off the double high tooth to a conventional 60-2 arrangement. See me do this here..

I really wanted to keep the trigger un touched so i could use the OE ECU.  that's pretty annoying if i didnt have to do that as i cant swap back now without swapping the flywheel...

That aside, if the trig pattern is changed to multi/missing 60-2 i should be ok?

Will try today (UK) and report back

Cheers,

Fraser

Share this post


Link to post
Share on other sites
56 minutes ago, Fraser said:

That aside, if the trig pattern is changed to multi/missing 60-2 i should be ok?

Yes, that is what I have done in the map I attached above.  

 

58 minutes ago, Fraser said:

I followed the help note in the Link manual which advised i had to machine off the double high tooth to a conventional 60-2 arrangement. See me do this here..

That note just says some Clio engines will not run correctly with the Renault Clio triggermode and the solution is to modify it as you have done.  This is an old note from before my time so I dont know the reason for it or what causes some to not work or how common that problem is, so chances are it probably didnt need to be modified but anyway at least you have now eliminated any chance of that problem.  The only thing you missed is that same note also says to use multi-tooth/missing trigger mode with 60-2.

Share this post


Link to post
Share on other sites

Fair point.  I will try the map changes soon and let you know.  Just my luck that it actually ran decent....with wrong polarity, and trigger pattern! or i'd have changed it earlier.

Next time the engine is out i'll swap the flywheels back and try.

 

why is the amplitude so much greater with the reversed polarity?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×