Help! Non-starter after Gearbox Change

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Hi all

I've just gone through the pain of swapping the gearbox on my Trophy.
The thing now won't start.

It cranks for a few seconds on most tries of the key (sometimes you get nothing, but most times you get a few seconds) but never fires.
It ran fine before the work started. The work has carried on over about 6 weeks so reasonably long time without a battery.
I have put a new battery in to be sure its not that (no change)

Details I have ascertained so far:

1) The immobiliser light is solid red. I think this means functioning correctly? I have also tried both keys.
2) The fuel pump does not prime. If I bridge the terminals in the relay under the bonnet it primes but it never does it on its own. Also, never 12v at the signal of this relay so the relay "switch" is not being demanded (from the ECU?). Also, when this relay is bridged, there is no change in behaviour. It still cranks but does not fire.

My thoughts are that maybe the crank sensor somehow got damaged? Is this something that can happen? Its bolted back in place and there is no adjustment on it so I assume it just sort of works. I also don't see why this would prevent the fuel pump from priming but maybe the priming is triggered from RPM?

Or could it be the ECU? Has that gone pop?

Or is it the dreaded immobiliser?

Any thoughts from those more experienced gratefully received!
 

Oracle

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To clarify point #1 - the solid light NEVER extinguishes

Mick from Diamond words.

The light staying on solid is saying the immobiliser has been disarmed but there is a wiring fault which is stopping an important item from reporting in and so starting the car is prohibited.

Chances are the UCH itself is fine.
 

Oracle

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Check 5 Amp fuse 3

CLIO ENGINE BAY FUSEBOX.jpg

Swap relay J with aircon fan relay E to eliminate the relay.

CLIO ENGINE BAY RELAY DIAGRAM.jpg

Check continuity from fuse 3 to relay J, if good and fuse or relay are not at fault, check continuity of white wire from relay J to ECU

pin 10



CLIO ENGINE BAY ECU 90 PIN CONNECTOR.jpg

PH2 172 & 182  ECU 12V SUPPLY WIRE a.jpg

Is the wavy orange electrical fault light in the centre of the instrument display illuminated?

Moving the engine loom about removing the box has probably separated a corroding wire.

As you can see from the last picture, I have had this occur.

Good luck.
 
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