Another poor Clio owner with starting problems!

[popes]

Long story short I've got that starting gremlin problem. No Fuel pump or Spark on key on.
Immobiliser light stays solid on key on, starter motor running for 3 seconds then goes out, I've changed the crank shaft sensor still not starting, RAC checked all electrical relay connections and battery ect.. and swapped the three black relays still nothing and was unable to connect to the ECU. I have checked and found supply from fuse 5A to terminal 38 ECU ok and returns 3, 28, 33 & 67 ok, 30A supply ok to the fuel pump and injection locking relay, 15A fuse feeding fuel pump control and terminal 29 ECU ok, cables to the TDC sensor 54 & 24 ECU ok I bypassed the B2 terminal down to ground on the fuel pump relay, pump runs but still not starting, opened up the ECU all looks ok. The drawing im working on shows terminal B2 (fuel pump relay) return going to ter 9 ECU but when I checked there is no cable in term 9 ECU getting dark so will have to check that tomorrow, but in the mean time any technical advice would be greatfuly received.

 

[MicKPM]

I sound like a broken record today with this... needs proper diagnostics mate.

The red light staying on indicates there is a connection problem somewhere on the car and its not necesarily on the ECM circuit (Confirmed by the UCH allowing the starter to run for 3 secs). It could be a wiring fault or a silly piece of hardware just given up but what i'm getting at is you will need to look at all the systems power/earths and then the CAN Bus network to see whats actually stopping the system from authorising the running.

Mick

 

[poriordan]

hi thought id throw this out there the little red switch hasnt popped has it

 

[popes]

Yay found the fault!!!! I got hold of a diagnostic box (Mac Tools) plugged it in and it would not communicate. So I thought I'll have one more wiring continuity check, this time with the ECU disconnected and the key in aux position, as I was checking for voltage Terminal 30 ECU plug was showing low volts so I run in another cable from fuse3 cut and crimped onto the terminal 30 and reconnected the ECU, guess what I now fires up:clap: also with no fault codes.
So if you have this problem try connecting to the ECU with a diagnostic box if you find you are unable to connect check feed from fuse3 (5A) to terminal 30 ECU and auxilary fuse 5 15A (which also feeds the fuel pump relay) to terminal 29 ECU if they are ok check returns 3,28 & 33. Hope you find this useful.

 

[popes]

Also I found that you don't need the ECM plugged in to turn over the engine, the starter motor is wired independently to the ECM. The ECM controls the Fuel pump relay and Injection locking relay ect....