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Hadn't used he car for 6 weeks and the battery is totally dead. Can't open the doors with the key fob to open the hood. Is there any way to open the door?
Mine is a 2018 RX350, same GEN 4 as yours. You are correct with the fact that you can use the key and turn it twice to unlock all the doors IF the battery is good. I mentioned that I could actually hear the door lock solenoids fire when I used the key with the battery connected. With the battery disconnected that didn't happen. With the battery disconnected, turning the key in the door lock cylinder only raised the door lock button and unlocked the drivers door. I'll post a link to the video. I uploaded it to YouTube.
The 'Like' button is insufficient. Trying things on our own vehicles to answer forum questions is a good way to give back to the community. Disconnecting the battery and trying what you did in the stinking cold weather is above and beyond - and deserving of the Distinguished Service Medal. Well done, and thank you.
Now that I realize I cannot depend on the "mechanical key" to open the vehicle in case someone accidentally leaves the headlights on, or the main battery dies for some other reason with the doors locked, I decided to install a hidden backup hood release. Lexus conveniently provided a second set of cable mount fittings on the latch, I assume to accommodate right-hand-drive models. I already had a spare bicycle brake cable that had been gathering dust for probably 25 years, so this was a no-cost project that only required 30 minutes of time. The operating end is hidden from view by the casual observer, and works perfectly.
Details in attached images.
Image 1: Hood latch. Extra fittings for a right side release cable are circled (assumed to be a provision for right-hand-drive models).
Image 2: Bicycle brake cable installed. Yellow material is a liberal application of lithium grease.
Image 3: Cable routing along the front apron.
Image 4: Cable routing along the right fender. From there, it passes under the washer fluid filler and then down toward the right fog light. A piece of plastic wiring harness loom was added to protect the cable.
Image 5: Remove these 4 10mm screws to lower the front right valence section. Reach in and position the cable in the desired location.
Image 6: I chose to have the cable exit at the edge of the lower engine cover. It tucks up on top of the cover and is not visible.
Image 7: A short piece of shrink tubing, heated only at the tip, serves as a protective weather sheath. The exposed end of the cable is liberally greased as well, with waterproof grease. The sheath slides off easily in order to operate the emergency hood release.
Now that I realize I cannot depend on the "mechanical key" to open the vehicle in case someone accidentally leaves the headlights on, or the main battery dies for some other reason with the doors locked, I decided to install a hidden backup hood release. Lexus conveniently provided a second set of cable mount fittings on the latch, I assume to accommodate right-hand-drive models. I already had a spare bicycle brake cable that had been gathering dust for probably 25 years, so this was a no-cost project that only required 30 minutes of time. The operating end is hidden from view by the casual observer, and works perfectly.
Details in attached images.
Image 1: Hood latch. Extra fittings for a right side release cable are circled (assumed to be a provision for right-hand-drive models).
Image 2: Bicycle brake cable installed. Yellow material is a liberal application of lithium grease.
Image 3: Cable routing along the front apron.
Image 4: Cable routing along the right fender. From there, it passes under the washer fluid filler and then down toward the right fog light. A piece of plastic wiring harness loom was added to protect the cable.
Image 5: Remove these 4 10mm screws to lower the front right valence section. Reach in and position the cable in the desired location.
Image 6: I chose to have the cable exit at the edge of the lower engine cover. It tucks up on top of the cover and is not visible.
Image 7: A short piece of shrink tubing, heated only at the tip, serves as a protective weather sheath. The exposed end of the cable is liberally greased as well, with waterproof grease. The sheath slides off easily in order to operate the emergency hood release.
Use
Even with a dead battery you can use the mechanical key that is inside your key fob to open the driver side door.
Now that I realize I cannot depend on the "mechanical key" to open the vehicle in case someone accidentally leaves the headlights on, or the main battery dies for some other reason with the doors locked, I decided to install a hidden backup hood release. Lexus conveniently provided a second set of cable mount fittings on the latch, I assume to accommodate right-hand-drive models. I already had a spare bicycle brake cable that had been gathering dust for probably 25 years, so this was a no-cost project that only required 30 minutes of time. The operating end is hidden from view by the casual observer, and works perfectly.
Details in attached images.
Image 1: Hood latch. Extra fittings for a right side release cable are circled (assumed to be a provision for right-hand-drive models).
Image 2: Bicycle brake cable installed. Yellow material is a liberal application of lithium grease.
Image 3: Cable routing along the front apron.
Image 4: Cable routing along the right fender. From there, it passes under the washer fluid filler and then down toward the right fog light. A piece of plastic wiring harness loom was added to protect the cable.
Image 5: Remove these 4 10mm screws to lower the front right valence section. Reach in and position the cable in the desired location.
Image 6: I chose to have the cable exit at the edge of the lower engine cover. It tucks up on top of the cover and is not visible.
Image 7: A short piece of shrink tubing, heated only at the tip, serves as a protective weather sheath. The exposed end of the cable is liberally greased as well, with waterproof grease. The sheath slides off easily in order to operate the emergency hood release.
Use
Even with a dead battery you can use the mechanical key that is inside your key fob to open the driver side door.
I have a 2017 RX350 and I am unable to open the car or hood. The car battery is dead, and the mechanical key will not work (I have a suspicion that the mechanical key is not a truly "mechanical" key but need the car battery to open the door with an electrical coil).
I have a 2017 RX350 and I am unable to open the car or hood. The car battery is dead, and the mechanical key will not work (I have a suspicion that the mechanical key is not a truly "mechanical" key but need the car battery to open the door with an electrical coil).
The manual says to use the mechanical key if "the battery is depleted". The procedure consists of 3 steps and is shown on page 662 of your owners manual.
Driver door has a lock cylinder. Pull the physical key out from the fob and pull the driver door handle and look in the gap between the door handle and door panel. I believe the cylinder is pointing down.
The manual on page 662 says that the mechanical key can be used to open the door when "the electronic key cannot be used because the battery is depleted", they mean the electronic key battery. In my case, the electronic key battery is fine, but the car battery is not.
I am pretty sure this is what is meant because it says on the same page that "turning the key again unlocks the other doors". The only way this could be done is that the car battery is used to activate the solenoids of the other doors (not mechanically).
The manual on page 662 says that the mechanical key can be used to open the door when "the electronic key cannot be used because the battery is depleted", they mean the electronic key battery. In my case, the electronic key battery is fine, but the car battery is not.
I am pretty sure this is what is meant because it says on the same page that "turning the key again unlocks the other doors". The only way this could be done is that the car battery is used to activate the solenoids of the other doors (not mechanically).
Did you try the mechanical key procedure? I'm curious myself now. We have a 17 and I just replaced the battery knowing it was almost five years old.
Yes, I have tried the mechanical key. It turns but does not open the door which is solenoid operated and needs the car battery to activate it even with the mechanical key, I understand that earlier RX350's could be opened mechanically with the mechanical key even with a dead car battery but this is no longer the case for the 4th generation RX350.
The mechanical key would therefore work for the 4th generation in the case of the electronic key battery depleted but with a good car battery.
06-06-19 | 06:12 AM
Dead Batttery
