Hi folks. What would stop both keys from not wanting to sync after a battery disconnect? Both previously working fine and previously synced via door method.

Cheers

Receiver antenna disconnected?

Shouldn’t be. Not been behind that panel for a while

For them to sync it needs both the keyswitch and CDL switch in the latch to be working and the receiver being able to receive the signal from the fob. A failed keyswitch isn't always obvious if you always lock with the fob as it is only used when the key is turned in the lock. So, you may have an iffy keyswitch or it could be an RF problem. If you've got a local source of RF, it may not be something that will cause battery drain but it might be something that desensitises the receiver. The range on my keyfob is much lower at my daughters house than at home as she has a mobile phone site pretty close by. Although the frequencies used are far away from the 433 MHz used by the fob, they are considerably stronger so the receiver is being desensitised so needs to see a stronger signal on the operating frequency. Waving the fob near to the rear window aerial means it works whereas at home I can lock and unlock the car from inside the house.

The latch was replaced last year with Marty’s refurb items. Maybe wiring? I noticed the obd port is dead again.

Struggling to chase this down. Would replacing passenger door latch with another have any relation?

Only if the door ajar switch is faulty and it thinks the passenger, or any, door is open as all doors must be closed for the sync to happen. It also needs the immobiliser to be off, keys won't sync if the alarm has been triggered or the immobiliser is set.

I've known this on another car, a 99 French spec diesel that lives just outside Paris that I look after for the owner. She's got 3 keys and after a set of batteries, all 3 synced no problem. A few months ago, she let the battery go flat by leaving the sidelights on. Took the battery off, charged it and when it was put back on, had to enter the EKA. That worked fine but the keys wouldn't sync, not one of them. Last time I was there I had a go and although all three were working fine, Nanocom reported that all microswitches were fine yet the keys will not sync. Mentioned it to Marty and he's known it in the past on odd occasions but has yet to find out why.

Head doer!!!

I’ve got a few spare latches on my breaker so will try a few combinations, and swap the RF receiver