Doors wont lock or unlock with fob or switch?

The front driver will not lock or unlock electronically, with the fob or with the door switches. Also, the rear doors will not lock or unlock in any fashion other than manually. The front passenger door works regardless of any method used. The front driver will lock\unlock with a manual key. Any of the buttons used on any door will lock the passenger door but no other doors. Have replaced the fob battery and also checked EVERY fuse and relay. Have tried resetting the door lock sequence from single door to all doors and back several times with no results. There is not a second fob lost in car.
Experienced mechanics share their insights in answering this question :
Hello. Further testing should be done to help solve your problem. Being that the door unlock reprogramming procedure has already been done and the fuses have been checked there’s not much left it could be. When you hit the unlock button you should hear a little noise in each of the doors. If you hear the noise that means that the motor inside of the door actuator is working therefore it is likely the actuator itself as the problem. Though if you do not hear any noise that means it is likely the motor inside of the actuator. The actuator motors are very common failure on Lexus. The Lexus Community is almost an uproar because the a L in Lexus should also stand for luxury but there have been widespread simple problems reported such as this. A technician such as those we have here at yourmechanic will be able to diagnose your door lock issue for you firsthand. But if you consider following the test I suggested that should help you narrow down to a solution as well.

It may also be a beneficial to take a door panel off and probe a multi meter to the door actuator connectors to ensure they are receiving the proper power and ground when the buttons are pressed. If they are that only leaves two things that can be at fault. The door actuator or the motor inside of the door actuator.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Replace the battery of the key fob. In many cases, this is why the doors of your Lexus refuse to lock or unlock when you press the button. Check the door actuator. This is best done by a professional mechanic because the actuator is located deep inside the doors of your Lexus.
If the battery dies, the fob chip loses power and will not open or close your car doors. To avoid such frustrations, ensure you are stocked with spare batteries or a backup key. Another major issue in the key fob is misaligned buttons and broken contacts. You can open the key fob to check if it has any issues.
A problem with one lock is probably due to the lock actuator or another malfunction inside the mechanism of the door itself. But if none of the power locks work, check the fuse box in your vehicle. A blown fuse can cause the power locks to stop working.
When your car key fob doesn`t unlock the doors, try every other entry mode to determine whether all connections are still intact. This could require the replacement of the entire lock system in certain circumstances, but it might also be as simple as replacing a simple screw.
If your key doesn`t turn in the lock, the problem may just be a poorly cut key. Test the lock with a key that was cut at a different time to be sure. If the key isn`t the problem, try lubricating the lock using powdered graphite or a silicone-based lubricant.
To program your keyless-entry remote, press and hold the “LOCK” and “UNLOCK” buttons on the key fob simultaneously until the locks cycle once more. This could take up to 30 seconds, so be patient.
If I change the battery in either the car or key fob do I have to reprogram the key fobs? No, The key fobs use non-volatile memory, meaning that they will never lose their programming if power to either the key fob itself or the module is lost.
One common reason the car door lock is stuck in the locked position is due to broken connections within the door panel or lock assembly. These include a broken link from either the handle, lock cylinder, or interior locking post/switch to the car door latch.
There are several factors that can cause a door lock actuator to fail. One is corrosion. Over time, moisture, oil, dust, and debris can enter the actuator or the mechanical links. These will react to form rust, which will weaken the mechanical links and can cause failure of the actuator.
The behind-the-scenes mechanism that locks and unlocks your vehicle`s doors with the push of a button is the power door-lock actuator. Mounted inside the door, it includes an electric motor, gears and linkage, or a cable that extends or retracts to operate the lock.
The system or actuator filter is blocked or clogged. The actuator ports are plugged with contaminants. The speed controls are closed. There is too much condensation.
Mode Door Actuators: The mode door actuator controls what vents have air flow, i.e. floor, panel or front, defrost, or any combination of those. Recirculation Door Actuators: The recirculation door actuator controls the intake of air into the system, either bringing outside air in or using inside air in recirculation.
Lock is stiff and difficult to open

Dirt and dust can sometimes find its way into a lock and build up over time. This can clog up the locking mechanism making it difficult to turn. You can apply some graphite spay or silicone based lubricant in the lock, put the key back in and turn it a few times.

A door lock relay can be located in four different places on a vehicle, including: Under the dash on the wall by the brake pedal. Under the dash in the middle of the cab behind the stereo. Under the dash behind the passenger air bag.
Without a programmed transponder key, you won`t be able to start your car. Car key programming is an essential procedure that your key fob needs to go through in order for it to operate and start the vehicle. Key replacement procedure has to be done the right way.
Car key sensor is not working: If the key is not working at all, it may be due to the drained battery, faulty fob, low car battery, or faulty keyless entry system (if applicable). You can try replacing the fob batteries, diagnosing the fob or towing the vehicle to a service centre to fix the issue.
If your key fob isn`t working after replacing the batteries, you may need to reprogram it or check for loose buttons and broken battery terminals. If your remote key fob isn`t working and you`ve already replaced the battery, you may need to reprogram the key.
Actuator failure – signs and symptoms

Complete loss of power, causing the vehicle to enter limp mode. Intermittent low pressure. Low boost. Overboost.

If it`s possible to lock out the actuator electrically so there is no current, it may be possible to perform the repairs on-site. For example, if you need a new motor or contactor, a technician will often be able to replace the parts without shutting down the whole line.
The average cost for a Door Lock Actuator Replacement is between $297 and $346. Labor costs are estimated between $95 and $120 while parts are priced between $202 and $226.
The door control module (DCM), also called a door control unit (DCU), is a type of automotive electronic that provides intelligent control for vehicle doors, and their peripheral electric parts and components, that enable features such as power windows, anti-pinch technology, central door locking, rearview mirror …

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Doors wont lock or unlock with fob or switch?
ANSWER : Hello. Further testing should be done to help solve your problem. Being that the door unlock reprogramming procedure has already been done and the fuses have been checked there’s not much left it could be. When you hit the unlock button you should hear a little noise in each of the doors. If you hear the noise that means that the motor inside of the door actuator is working therefore it is likely the actuator itself as the problem. Though if you do not hear any noise that means it is likely the motor inside of the actuator. The actuator motors are very common failure on Lexus. The Lexus Community is almost an uproar because the a L in Lexus should also stand for luxury but there have been widespread simple problems reported such as this. A technician such as those we have here at yourmechanic will be able to diagnose your door lock issue for you firsthand. But if you consider following the test I suggested that should help you narrow down to a solution as well.

It may also be a beneficial to take a door panel off and probe a multi meter to the door actuator connectors to ensure they are receiving the proper power and ground when the buttons are pressed. If they are that only leaves two things that can be at fault. The door actuator or the motor inside of the door actuator.

all doors lock only by inserting key in passenger side door and locking
ANSWER : Your central locking system may have been designed with a control module in the circuit. This is a small computer that is responsible for controlling the different functions of a particular system. It is possible that the module for your central locking system may have shorted out internally preventing particular functions from working properly. I would recommend having a certified technician test your central locking module to determine if all of its functions are working properly.

Driver and Passenger doors won’t lock, but I hear them click and see the locks twitch.
ANSWER : If the same problem is happening even when you use the inside door lock switch then the most likely cause of the locks not moving is going to be weak actuators. You should replace the drivers lock actuator first since it is used the most and you will see it fixes the problem. Then you can replace the other doors as needed.

Having problems with door locks on 08 Cadillac CTS. Driver side door especially and will not lock or unlock with key. Others loc
ANSWER : This is often related to a malfunctioning door lock actuator, a blown fuse or a faulty power door lock switch. When you use the door lock switch in the car it sends a signal to a relay which then activates an actuator inside the door. The actuator is the final step in the process in that it is a small motor with a set of gears that actually locks and unlocks the latch mechanism inside the door allowing the door to open. When this motor is bad, the latch mechanism will fail to operate and cause the door not to unlock as it is designed to. In the case of a bad door lock relay, the power, normally needed to send the signal from the switch when you activate it to the actuator motor is not there. This means the relay is not allowing the circuit to be completed and the actuator motor is not activated. Any of the above may cause your power door lock switches not to work properly and should be diagnosed by a qualified mechanic. I would suggest having a professional from YourMechanic come to your location to take a look at the door locks in your vehicle.

Doors lock and Unlock when vehicle is off and parked!
ANSWER : Hello, thank you for writing in. The vehicle may be having an issue with its body control module. Due to the locks doing this on their own, and the issue with the key-less entry (which works on its own circuitry), the issue is likely the components they have in common. This will include the body control module, fuse systems, or a short somewhere. Testing will need to be done when the system is experiencing the symptoms, and you may need to replicate them at the needed time. Due to the timing in which this happens, you will want to locate where the extra supply of power to the locks are coming from. Find this, and you likely will find your issue. For more help resolving the issue, contact our service department to schedule an appointment.

Driver side door lock button not working, and passenger side sliding door makes a buzzing noise
ANSWER : Hi there. These door issues are common on this vehicle. Most of the time the main issue is the master door lock switch on the driver door. It sounds like you already replaced that. As for the sliding door problem, most of the time, this is a failure within the door module or it can be a connection issue.

I typically take the door apart and check the connections on the module and inside of the door just to make sure that there is nothing apparent in there. If the connections and the wiring are fine, then I use a scan tool to check the module to see what the inputs and outputs are doing. If you need to have this looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your door problem and recommend a repair.

Door lock problems
ANSWER : Hi there. There is a resistor for the door locks that keep a voltage on the driver door lock cylinder to activate the secondary door locks electronically. If the resistor is leaking (losing power) it tends to cause the door locks to not work. You can try unlocking the driver door, then open the driver door and use the key to unlock the other doors. This will supply power directly to the driver door lock cylinder and bypass the resistor. If the other doors unlock, then the resistor needs replaced. If the doors do not unlock with the key and the driver door open, then the door lock cylinder on the driver door will need replaced. If you need further assistance with your doors not unlocking when turning the key twice, then seek out a professional, such as one from Your Mechanic, to help you.

Key fob won’t unlock or lock doors
ANSWER : I believe you should have a technician use a capable scan tool to test the immobilizer and security system of the vehicle. There are likely codes present that will lead you directly to the issue. Also have them test the EVTS because it is possibly interfering with the factory immobilizer system.

I’d recommend getting some help from a certified mechanic who has the tools and capability to diagnose the issue with your doors. Once this is done, an accurate repair can be made.