Lexus Troubleshooting Questions? Ask a Lexus Expert
Can you please clarify what is going on with the rear hatch? Are you saying that when you close the hatch it will lock the motor will draw the door down partially then it comes back up about an inch and the door adjar light comes on?
If you shut the power door function off so that the door has to close manually will it close draw the door tight and stay that way or does the still pop back slightly?
If you push the door down manually and continue to apply pressure to it or push on the door will it remain latched or does it not matter how much pressure you hold on the door to try and keep it closed and it still pops back open slightly? In other words will it still pop back open slightly even if your putting continual pressure on it while it tries to draw the latch tight?
You really only have two possible options here. Either the microswitch in the door latch itself is not detecting that the door is completely closed therefore it pops it back open or the initialization on the door has been lost. Normally though if you shut the power door feature switch off and close the door manually it will stay completely closed if it's initialization issue and not a switch. What you can try and do is a hard reset on the system by that I mean try first to have the hatch all the way open remove both battery cable ends isolate them from the battery then place a jumper wire across the two cable ends to dissipate all the capacitors and memories in the computers. Then after about 10 minutes remove the jumper wire reinstall the battery cable ends to the battery. Turn the power switch on for the rear door and see if it will close by pushing the button on the remote and see if the latch stays latched. If it does not and pops back open slightly then repeat the process but only with the door in the closed position. If that does not work either then you're probably looking at a bad latch assembly in the rear door. Without a scan tool that will read body codes from the body ECU it is difficult to say for sure if there was a switch malfunction usually it will set a code in the body ECU. Most generic code readers will not read the body ECU system.
On your last reply I had ask you to turn the switch off for the power rear door. There should be a switch on the instrument panel as I recall on this year that allows you to turn the power door system off so that the door has to be closed manually. This is what I needed you to try and do to see if the latch would stay closed if you manually close the rear hatch. Do you have the owners manual? There should be a location of the switch in the owners manual.
I just looked up this particular year and the override switch is inside the glove box. Turn the rear power door off and try the closed feature again and see if it stays closed. If it does then do the hard reset on the system with it totally in the latched or closed position.
Unfortunately there is no way to turn off that warning buzzer. As long as the body ECU does not see those close latch signal inputs it will keep beeping the buzzer for safety reasons. Let me know how it goes. And if you need any other input feel free to reply and I will get back to you. Please do not forget to rate the assistance that I provided to you at three or higher.
Unfortunately there's not much more that I can do in this type of format. You will need a scan tool that will access the body ECU so we can see what the position of the switches are and what's going on with the latch when it goes to the closed position. One of the limit switches is either bad or the latch itself is broken so that is not staying latched when it's pulled shut. If you live where rust and corrosion are an issue it's possible it could be corrosion in the latch not allowing it to stay shut.