12 replies to this topic

[Ebo100]

I'm still having problems getting my turbo to start. following on from this thread :- http://www.vx220.org...-pump-problems/

I have not been able to get any error codes on my scan gauge so called out a little man to read the codes and maybe reset the transponder or immobiliser that I have read about. When he plugged in his tech2 he could not connect to the ECU or engine but he could see the airbag. What would cause this?

 

To recap I have checked the loom of doom, all the relays and fuses, new battery fitted, I have sparks at all the plugs, the fuel pump is working fine on the bench and I have fuel pressure at the fuel rail with a nice healthy squirt out. I have taken the fuel rail off and I can see that none of the injectors are working.

 

Is this pointing to a fried ECU? If I was to take the plugs off the ECU could I check with a multi meter?

[siztenboots]

when you turn ignition to position II , do you get the click clack sound of throttle body checking itself after a couple of seconds , or is the engine completely quiet?

[Ebo100]

There is a click and then a high pitch whining noise similar to an electric motor turning very fast. The whining can be heard all the time the key is turned.

 

[Andrew aka Stuwy]

that wine is the fuel pump priming, the click is a good sound

[Ebo100]

The whine is from the engine bay around the fuel rail area. I have released the pressure on the fuel rail and now cannot hear the pump prime

[siztenboots]

you should hear the squeel of the stepping motor on the throttle body and hear it click clack

 

the tech2 not talking could be wiring , or you might just need to pull fuse 8 to hard reboot the ecu

[Ebo100]

The ECU reset has helped, and with copious pumping of the throttle I got it to fire but it would not run and died instantly.

I have my scangauge plugged in at it still says 'No Connection'

[Arno]

Sounds like the immobiliser is either dead or lost sync (or got 'de-paired') to the ECU.

 

The data on the OBD K-line from the plug under the dash to the ECU is routed through the immobiliser in the steering column, so if that no longer works you won't be able to talk to the ECU with a scantool anymore.

 

If the immobiliser is dead (or at least non-functional) you do get the effect that the engine starts and runs for 2 to 3 seconds and then the ECU cuts the engine as it did not get the required 'OK' from the immobiliser.

 

Bye, Arno.

[siztenboots]

If these units are becoming trouble I could map out immobiliser.

[Ebo100]

Sounds like the immobiliser is either dead or lost sync (or got 'de-paired') to the ECU.

 

The data on the OBD K-line from the plug under the dash to the ECU is routed through the immobiliser in the steering column, so if that no longer works you won't be able to talk to the ECU with a scantool anymore.

 

If the immobiliser is dead (or at least non-functional) you do get the effect that the engine starts and runs for 2 to 3 seconds and then the ECU cuts the engine as it did not get the required 'OK' from the immobiliser.

 

Bye, Arno.

 

So how do I get round this Arno? new column immobiliser and get it coded/sync to the ECU

[Ebo100]

If these units are becoming trouble I could map out immobiliser.

 

How would this work Steve if there is no connection through the OBD?

[siztenboots]

 

If these units are becoming trouble I could map out immobiliser.

 

How would this work Steve if there is no connection through the OBD?

 

 

bootmode , thats why I said pull the fuse 8

 

its happened to me with a remap and the checksum data was wrong , ecu just goes deadly quiet.

 

I've got some more tools to work with, something which lets me edit and update the 95080 chip (-29F400BB) , without having to unpair it or desolder it.

[Arno]

So how do I get round this Arno? new column immobiliser and get it coded/sync to the ECU

First you may want to check that the wiring is all OK around the coumn and the immobiliser (with it's antenna ring around the ignition barrel) hasn't simply lost power for some reason.

 

Fuse FB7 and FB8 are both OK?

 

http://speedsterclub...Immobiliser.pdf

 

Would be the easiest explanation if there's some issue and the immobiliser is simply not powered up.

 

If it's FUBAR then there may be somewhat of a challenge. Normally the ECU can only be paired to a new immobiliser if the original pairing has been removed/erased with a TECH2 or similar while it is operating normally. This is to stop people just bringing their own immobiliser and transponder and pluggin  these in  to start the car.

 

If the immbobiliser unit has died then you can't cleanly 'un-pair' them anymore and the ECU won't accept a new one. Normally this would mean you'd need a complete replacement set of ECU + immobiliser.

 

However..

 

Hopefully with the way the Motronic ECU's have been cracked on the turbo for some time it may be possible to wire the OBD plug K-line directly to the ECU and tell the ECU to clear it's pairing and then fit a new immobiliser and re-pair these.

 

Or forego the immobiliser completely (insurance may not like this) and have it de-programmed from the ECU and make the OBD bypass permanent. It then just becomes a dead/useless component.

 

Bye, Arno.