Drcoffee

There are so many problems it seems with the electronic door locks on the first gen RX300. I have a '99 worth $4000 I don't need the security system anymore. So here is my issue. When I lock the doors with the key fob, the automatic headlights don't turn off but the doors stay locked. When I unlock the doors with the key fob, the first push no sound, and door unlocks, two pushes on the fob and it beeps to let me know all the doors are unlocked. The drivers door did unlock with the first push, just no beep. If I leave the door open, the car will re-lock in 30 seconds as if it does not know the door is open. Same for the front passenger door. If I open the rear 3 doors, no re-lock. Everything is normal.

I replaced the front left door actuator with an OEM new unit. same problem. I took the door panel off this morning and pulled it out and reconnected the electric plugs and observed the function through all its possible operations. I can't seem to find anything obvious that's causing an issue. Here is where I am at.

I disconnected the latch sensor wire, the smaller, two wire connector on the latch mechanism. So the chime no longer chimes when the door is open. I'm okay with that. The door locks no longer appear to mysteriously re-lock themselves while the door is open.

--->> My question is this. What else than does that latch sensor control? Does it affect the security system or vital computer functions?

JAB

I think it also controls the dome light.

salimshah

DrCoffee;

I generally try to focus on the technical side, but I disagree with your chain of thoughts on loss/safety [You just focused on the loss].

Due to immobilizer you dont have to worry too much on some one stealing the RX. Without the lock your contents more likely to be stolen.

You will compromise the safety by allowing some one to enter unlocked vehicle. <== Please do not overlook that possibility.

Salim

Drcoffee

would it be beneficial to reprogram the key fobs? I wonder if when I disconnected my battery, if that affected the lock system.

salimshah

My comments in orange.

Salim

hypervish

It's my understanding that the RX300 does not have a CBEST option to lock the door locks when the car is in motion.

Drcoffee

I bought a cable and software for the Toyota CBEST system and wouldn't you know, it operates on XP and WIn7 32bit. I have two laptops that both are 64bit

Now what it is doing is when I stop for gas, I get out fill up, get back in, close the door and the door locks cycle with two clicks. I will try re-programming a fob and see what comes of it.

Drcoffee

What would happen if I disconnect the engine hood courtey switch? The switch that knows if the hood is open or closed. Would this defeat the security system? I am tired of chasing ghosts. The doors keep re-locking unless I open the rear doors. If I disconnect the hood switch, I assume the security stystem does not activate. Is that correct?

Reprogramming the fobs made no difference. None of this started until I disconnected the battery. Did I put the system into passive mode and if so, how do I change it back?

Drcoffee

So far so good. I seemed to have stumbled on a way to disable the ridiculous security system with all the issues I have discussed above. The doors relock even when the drivers door is open. The locks cycle lock unlock as I drive off from park. Alarm sounds unless I unlock all doors with the fob with two presses.

What I did was unplug the engine hood courtesy switch on the backside of the hood latch. It needs continuity when the hood is open. Which means I shorted the harness plug by pushing a short wire, bare on both ends into the female plug. I also sealed the end of the plug with hot melt glue to seal it from water and zip tied it out of the way. Now the computer believes the hood is open and the security system will not arm until it knows its closed. At least so far. I tested it two different ways and the doors do not re-lock as they previously did. All lock functions work as they should.

caphook

My driver door will not lock with the key fob. All other doors lock. I can manually lock the door with the inside rocker type ****.
Then the key fob will unlock it but not re lock it.

Any suggestions.


Cap hook

carguy07

It's the actuator: https://www.clublexus.com/forums/rx-...-write-up.html