Is the ecu buggered?

[fearless]

French electrics. What a prick.

So yesterday night had to get the RAC out as the 172 wouldn't start. Long story short turns out the injector locking relay in the engine bay wasn't switching. Swapped relays around and still no good so ruled out a dodgy relay. Bridged the circuit in the end and its all good, starts runs everything.

Got home today and consulted the wiring diagrams and it looks like the ecu controls the switching earth on the relay. Feed comes of the feed that was bridged so cant be that.

So either leaves either the ecu has apparently fucked up in a very specific way or there must be a break in a wire somewhere. Problem is I drove it Friday night, parked up and Saturday it just wouldn't start. So something has spontaneously fucked up, which seems unlikely to be a wire break.

So thoughts? Anyone every had a very specific ecu fault? or is a wire tracing game?

Cheers

 

[MikeClio172SPT]

You need to see if the above mentioned relay is getting all its feeds, including its earth's. Also probe that feed from the ECU, if u can find what wire, & see if its triggering.

 

[fraz101]

There is a green wire from the injection locking relay which goes to the injection ecu that is notorious for corroding, do a continuity test between the realy terminal and the ecu...

 

[fearless]

aha, that is exactly my next plan. Just need to get hold of a tester though.

If it is that one, is it a case of splicing in a new wire?

 

[fraz101]

Yeah cut out the corroded wire and add a new piece of cable

 

[fearless]

There is a green wire from the injection locking relay which goes to the injection ecu that is notorious for corroding, do a continuity test between the realy terminal and the ecu...

Give that man a potato.

Its a white wire that runs to pin 10 on the ecu. Continuity test gave a big fat zero so spliced in a rough new wire just now in the dark and all is back to normal. Will crack out the soldering iron at the weekend and make a more professional job of it but I'm a happy man.

How in the hell do you get the ecu cover back on though? I'm tempted to take a hammer to it.

 

[fraz101]

Give that man a potato.

Its a white wire that runs to pin 10 on the ecu. Continuity test gave a big fat zero so spliced in a rough new wire just now in the dark and all is back to normal. Will crack out the soldering iron at the weekend and make a more professional job of it but I'm a happy man.

How in the hell do you get the ecu cover back on though? I'm tempted to take a hammer to it.

It's getting them off thats normally difficult.....!

Glad u got it sorted mate.