Car does not start with button BUT...

[qwertymk4]

Hello All

 

New to this forum and to FORD 

Have this very interesting problem with my Ford Mondeo MK4 2009 2.0TDCI Manual Titanium with Button start.

It had a small crash to front passenger side (UK model so left) knee airbag deployed along with both front seat belts. I have replaced Airbag and Seatbelts, cleared codes but did not replace Airbag ECU as was able to delete crash data (there was an option on diagnostic device I was using) and that worked. No airbag light no problems with that. 

BUT The car will not start if I press the start button. (bought car after crash so don't know if its linked with crash)

I have checked all fuses. (clear)

Checked Starter( works)

Thing we found is that Starter relay receives signal when button pressed, Clutch pressed it sends signal to engine ECU but earth does not come from ECU.

If you give earth directly to starter Relay and push button car starts. SO engine ECU does not give EARTH to Starter Relay. 

I have also checked the wire that goes from relay to ecu and it is not damaged. 

 

Any smart people out there that know anything about it?

 

Any questions i will answer asap 

 

Could it be linked to the crash? but never heard of that before as we did have other cars that start and drive after crash with airbags deployed.