My otherwise "perfect" Daily driver - '98 Camry V6 has developed a l problem with it's Central Locking system.
At first, I thought it was (my) advancing senility, forgetting to lock the car.... but eventually realized that it was randomly unlocking itself. First it was only doing it overnight, or a long period of standing, but became more brazen and would send an 'UNlock' - ALWAY unlock, never LOCK - pulse to all doors while driving. This was disconcerting but still safe.
Then it started to flash the hazards a couple of times whenever it did this. Usually twice, then occasionally / continuously.... as I drove... Not a great look for other traffic ! Oddly enough, operating a turn signal for a few flashes usually stopped the hazards, as did holding "LOCK" on the dash swich, - mostly. That alone is worrying, as it suggests the same module for DOORS, is affected by turn indicators...
Due to only having one (original, 1998 vintage battery...) remote fob, I've been using the key to lock/unlock, and this is where the first clue hit me over the head. Doing either would sometimes result in a series of pulses - usually UNlocking... which points to the lock-switch as being on the way out. - Very sensitive to the slightest amount of rotation... So yes, the switch felt like the villain. Easy solution; - Use the fob only.
Round One:- , a pair of new GENUINE Toyota remote fobs programmed for Two Stage Unlocking with the surviving original.
Nope, still would totally unlock overnight.
Round Two:- unplugging door-lock switch, fortunately they missed hiding it, so only needed to remove driver's door card.😉 Just done that, so no idea if that will work. Yet.
'Everyone' blames a faulty actuator for weird faults, particularly the Driver's door, but....
EDIT. Anolther evening and morning.... parked all day out in the sun - previously a sure-fire way to generate the fault - and it's behaving itself. I reckon it always was the switch operated by the door key. Interesting, as unlike previous vehicles, turning the key in the lock ONLY turns the switch, not the door locking mechanicals.
- Or to put it another way, my car is now 100% "Keyless Entry" ;))