Not cranking - Focus Mk3 1.0 2014 (intermittent)

[AlSeventyFive]

Hello folks

First post on here - seeking some expertise to bounce ideas around on my 2014 Focus which is beginning to test my normally calm composure! :)

Symptoms:

• Intermittent not cranking
• Audible click from engine, no start, can be multiple failed starts before it finally does
• Sometimes a “lazy” start - JUST like a high resistance current path or faulty battery
• Sometimes springs into life no problem
• Seemingly not temperature related, but seems to start consistently well during start-stop operation in traffic (has failed a couple of times, but nowhere near as common as a failure to key start)
• Ford have checked it and no trouble codes. No MIL light or any other dash warnings.

Have checked

• battery - replaced it with new/genuine as it was the “obvious” place to look. No improvement
• Starter motor current path – voltage drops are minimal and all connections appear in good order (checked when cranking).
• So you would have thought it was the starter solenoid right? Well…
  • Starter solenoid current path – shorting across KL30-KL87 starter relay pins results in a very snappy and responsive crank every time – therefore this wiring is OK and, apparently, the starter motor solenoid is therefore ok…
• So it’s the starter relay right?
  • Moved around the relays in the relay box (swap heated screen for starter: no improvement). Changed for new relay (well, new to me, 2^nd hand) to same spec – no improvement. Take the relay apart and clean the contacts – no improvement.

Given all of that, I’m left with the solenoid (ECM) side of the starter relay being the issue. However as far as I can tell the only thing back here is the ECM, controlling via a digital output. This should either work, or not, which is not compatible with the “audible click” I get from the engine, or the lazy starting I sometimes get.

But I need to stress it cranks responsively every time when I short across the relay KL30 and 87 positions, which indicates it’s not anything attached to the engine.

So I’m thinking that maybe the “click” is a red herring, perhaps some other device is moving on crank, but it sounds just like a starter solenoid to me…and I get no click when the starter relay is out so I doubt my own hypothesis here...

Before I start tearing into the loom, do any of you folks recognise the above symptoms as anything I’ve failed to check? I’ve scoured the forums and whilst there seems to be a few similar issues out there, none have been resolved which doesn’t bode well…

Many thanks in advance for any suggestions...

[AlSeventyFive]

Oh my good grief after struggling with this for weeks I've just checked the relay again and it failed to crank when shorting across the KL30/87 terminals. I must have done this tens of times previously and it cranked every time.

OK I'll get the starter motor changed and let's see where that gets me...

Typical. Apologies for the distraction...

Cheers!

[AlSeventyFive]

I've booked in for a new starter motor in a couple of days but have a few errands to run and I live near a hill, sooo...

Any advice for bump starting these engines? It failed to stop/start today in a queue, but luckily pointing down a hill - I naturally just went to bump start it but despite turning over well with the ignition on and a good battery it would not fire - do I need to move the key to "crank" position to get the ECU to start throwing in fuel and sparks? I did not try this...

Cheers