Keyless entry problems

rodenal · 10 Jan 2018 at 17:26

Bit of an odd issue developed with my keyless entry on the focus.

In the last couple of days none of the door sensors will lock or unlock the car - but oddly the boot will still open without being unlocked first.

I initially thought it was potentially just the sensors playing up in the cold but it's too consistent an issue to be that now.

Pretty much ruled out individual sensors as all four doors worked fine, now none do. All fuses that I can see relating to the system are fine. Don't think any of the relays do much for it.

Scanned with forscan (on my phone, will check using a laptop too) and can't find any error codes relating to the keyless system at all. Expected to find some sort of communication error or an outright fault with the bcm or similar.

Also sure it isn't the batteries in the keys as neither work on the doors but both open the boot. Car locks/unlocks fine with the fob

Only things left that I can think of are the battery nearing the end of its life or an antenna issue (but again would expect a code). Will stick a voltmeter over battery at the weekend but I'd expect to find more issues than just keyless funnyness if this was my issue.

I'm otherwise pretty much stumped and it'll need to go to ford - any other ideas first?

Raymond Lin · 10 Jan 2018 at 17:30

Try the spare key.

rodenal · 10 Jan 2018 at 17:31

See above. Both work to remotely open, Neither trigger the keyless system

Raymond Lin · 10 Jan 2018 at 17:32

Try new battery then next?

I found that the battery in my old Yaris with Keyless, its lifespan of it is about 2 years. When did you last change it?

rodenal · 10 Jan 2018 at 17:34

The batteries are only a few months old (with Duracell batteries so not as if it's no name rubbish in them) and the car whinges for a long time as they start to die.

Plus it has no problem detecting when the keys are inside the car

Howard · 10 Jan 2018 at 18:25

Have you tried disconnecting the car battery for a little while to “reboot” everything? This cured a problem with my electric memory seat.

rodenal · 10 Jan 2018 at 18:33

No but it's a fair point I'll give it a try when I'm checking the main battery

rodenal · 12 Jan 2018 at 16:51

Checked battery today and disconnected for a while as a last ditch attempt. Last night I forced the bcm to reset itself too through Forscan but none have had any impact.

Needs a dealer visit I think - my level of confidence in them not to waste time and potentially my money when the car isn't throwing up codes isn't high unfortunately

Dangerous Dave · 12 Jan 2018 at 16:57

Some RSs are having this problem, the cold weather was freezing moisture in the mechanism in the door handle and damaging it. New door handles sorted it.

rodenal · 12 Jan 2018 at 17:02

Would happen to every single handle though (or at least not all at the same time) would it? 4 handles failing at the same time seems pretty unlikely

Dangerous Dave · 12 Jan 2018 at 19:38

rodenal said:
Would happen to every single handle though (or at least not all at the same time) would it? 4 handles failing at the same time seems pretty unlikely

Not sure some were having multiple handles replaced others started working after the temperature had risen. I will try and find the thread I can't remember where I was reading about it.

rodenal · 13 Jan 2018 at 16:09

I reckon you're on to something - just cleaned then warmed them up with near boiling water and they now work again (albeit don't react as quickly as they probably should)

Been hunting around and it seems ford initially started taking the handles apart, cleaning them out and putting on a temporary protection of sorts.