I have a 2004 Toyota Estima Hybrid and it has a single-button key-fob to lock/unlock doors. It started struggling to work awhile back and I thought it might be the keyfob-battery so I replaced it, but no joy. Now it almost never locks or unlocks remotely.
Central locking using the key works fine: if I unlock the driver door, all doors unlock. The keyfob signal is getting received - I can hear the solenoids energizing and watch the lock-levers in the doors vibrate. It's as if it was somehow too "weak" to lock or unlock the car. Perhaps one or more locks or solenoids need lubrication? Does using the mechanical lock generate a bigger pulse to the solenoids than when the keyfob is pressed? It doesn't seem particularly difficult to lock/unlock using the key. Just wondering if anyone has experienced a similar problem and found a solution.