marylandlp

i'm having a problem trying to troubleshoot the warning buzzer circuit .Normally,the warning buzzer beeps twice when the trunk begins to open .It will also beep twice when you press the button to close the trunk.Yesterday I noticed that the warning no longer sounds when i open the trunk,but still beeps when i close the trunk.I examined he trunk closer ,but couldn't find the buzzer or an activator for the beep generator.The service manual was worthless.Has anyone had a similar problem and,if so, how was it repaired.? tx

Dema

In my case it may beep or not when I open, but always beeps during closing. My car is new and it was from beginning, so perhaps it is normal to do not beep consistently at open?

marylandlp

I have had similar intermittent problems when opening the trunk.I would appreciate any feedback from other members on the operation of the warning buzzer when the trunk is opening tx.

jmcraney

I don't think either of you have a problem with your car - it's more of a problem of knowing what is normal.

If the trunk is open, for whatever reason, if you press the "close" button on the lower lip of the trunk, a buzzer, located in the trunk area will beep twice as the trunk closes.

If you open the trunk using the dash button, located near the drivers left knee, there is no beep.

If you open the trunk, by pressing the "open" button that is located under the center line of the lip of the trunk you will get one beep. This beeper is the same beeper that signals operation of the door locks via the wireless remote key. The beep you hear in this operation signals a transponder response from the remote key that you are carrying. It is possible to silence or control the volume of this beep by adjusting the volume control under the dash.

marylandlp

jmcraney:
thanks for your reply.i tried to verify if a problem really existed as you suggested in your responce.i didn't get the buzzer when i opened the trunk from the outside button on the trunk,nor did i get it when i locked or unlocked the doors,or opened the trunk with the remote.i was pretty sure it was the buzzer above the wheel well,so i pulled it and put 12 volts across the terminals.i heard a slight tweet .i tried it several times all with the same result.i was pretty sure the buzzer was bad so i bought a new buzzer and installed it.same result in all four tests.i put 12v.on the terminals of the new buzzer.again,slight tweet onlly.i then decided to measure the voltage at the connector to the buzzer.nothing.there was no voltage at the connector going to the volume adjustment **** under the dash.everything works fine except the buzzer circuit.has anyone ever put 12 v.on the buzzer.i don't think the buzzer is my problem,but i would like to know whether the new buzzer is defective.

jmcraney

The Volume control **** can be seen in this picture, directly above the accelerator pedal, just to the right of the TPMS Set button.

Lextrician

wow never really looked down there!!! still learning stuff about this car..

marylandlp

I rotated the volume control **** to see whether it might be in the off position.It wasn't.Does anyone know what component generates the beep when the doors lock/unlock and when the trunk opens.I originally thought it was the external buzzer located in the wheelwell over the left front wheel.Now,i don't believe that its the beeper i'm looking for.I took it to a lexus dealer the other day and he couldn't find the problem and recommended i bring it in and leave it for several days.i'm not impressed.

marylandlp

jmcraney,Where is the transponder that you refer to in your posting located?

jmcraney

marylandlp,

The "sounder" or beeper that signals operation of the wireless key seems to be located in or near the left front wheel-well.

When I used the term "transponder" I am referring to the remote key itself. It acts as a transponder in the operation of the hand operated switch on the trunk.

If you will check Webster for the definition of transponder you will see that it is: a radio or radar set that upon receiving a designated signal emits a radio signal of its own and that is used especially for the detection, identification, and location of objects and in satellites for relaying communications signals

When you press that button under the lip of the trunk, a low power, directional radio frequency transmitter in the car sends a coded signal directed toward the rear of the car. The remote key must be located within about 6 feet of the car and directly behind the car to receive this signal. If the remote key receives and recognizes this signal it will transmit a low power, coded radio frequency signal and if the car recognizes this signal then the car will operate a solenoid to release the trunk lid.

marylandlp

After taking the car to two lexus dealers to repair the problem(neither was able to fix the problem),i finally decided to take a closer look at the wiring.When i was looking for the turn signal flasher to connect the new mirror turn signal wires to,i removed the bottom panel where the volume contol for the buzzer and the tpm reset button were.On the right side of the panel there are three connectors.One was clearly for the reset button.the other two were similar.i was in a hurry to button up the area and reversed the two other connectors thereby disconnecting the volume controller and opening the circuit to the buzzer.Works fine now.