Front doors not locking with fob.

I have two things wrong with my car. First off, when I press the fob I can hear the rear doors locks, but not the front doors. From the front door arm controls, the back door locks work but not the front doors. I have to manually lock the passenger's side door and use the key to lock the driver's side front door. Second, I have two warning lights on the dashboard: Check Tire Pressure and the Air Bag light.
Experienced mechanics share their insights in answering this question :
The front door lock actuators are controlled by the their respective door switch units. The rear lock actuators are controlled by the Body Control Module. When the key fob is pressed to lock or unlock. The Body Control Module receives the request and then locks/unlocks rear doors and sends a signal to both the drivers door and passenger front door switch assemblies over a computer data line to lock/unlock front doors. Since the rear door locks are operating, one of two things is happening, either the door lock/unlock request is being interrupted on the computer data line or the Body Control Module is not sending the request to lock/unlock doors to the data line. One way to see if the problem lies with the data line or the Body Control Module is to try to lock or unlock all doors from the driver’s door switch. If the rear doors do not lock/unlock then the data line to the Body Control Module is open and will need to be traced to locate the open circuit and repaired. You may want to enlist the help of a mechanic, like one from YourMechanic who can scope out the data line to see if the signal is being interrupted and to locate and repair the open circuit.

How to Identify and Fix Common car Problems ?

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

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.
In many cases, when a door doesn`t lock, it`s due to the door latch rather than the lock itself. This is usually because the latch is not aligning with the hole in the strike plate. While this can be easily fixed, it`s always best to call a professional locksmith rather than attempting to repair it yourself.
A blown fuse is the common hurdle in locking doors properly. Car doors rely on this fuse`s command to lock or unlock. The fuse is usually located under the glove box (passenger`s side) and can get blown due to high voltage. The fuse is cheaper and can be easily replaced at home.
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.
Check and replace the key fob battery as needed. Take the key fob apart and check for broken contacts or misaligned buttons. Reprogram your remote yourself or have a professional do it. Replace your remote if necessary.
Believe it or not, a small bottle of alcohol-based hand sanitizer is all you need to open a frozen lock. Hand sanitizers work because the alcohol in them melts the ice that has made the lock seize up. Simply pour it on the key and wiggle the key in and out of the lock for a moment to loosen it up.
A door locking motor is fitted to each door and connected to a control box located under the fascia in front of the steering wheel. A 20 amp fuse is incorporated to protect the System, see figure 1.
As the battery wears out however, the range and signal strength of the fob transmitter will be reduced. If you notice that your key remote does not unlock your car, lock your car, or start the engine for those with the automatic start button as early as it should, it`s probably time to replace the battery.
How Do I Know That My Door Lock Relay Is Malfunctioning? If the doors refuse to lock when you press the lock button but unlocks when you press unlock button.
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.
If your key fob still isn`t functioning after you`ve replaced the batteries, the problem may be with the internal contacts, such as the buttons or the battery connector terminals. It`s also possible that your car and remote unpaired from each other after you took the batteries out.
Typically, a car fob battery should last between three and four years. Additionally, there are a number of signs that will tell you when your fob battery is dying. The first sign is reduced signal strength. Most modern fobs can send a signal to your vehicle from up to 50 feet away.
If your key fob still isn`t functioning after you`ve replaced the batteries, the problem may be with the internal contacts, such as the buttons or the battery connector terminals. It`s also possible that your car and remote unpaired from each other after you took the batteries out.
Typically, a car fob battery should last between three and four years. Additionally, there are a number of signs that will tell you when your fob battery is dying. The first sign is reduced signal strength. Most modern fobs can send a signal to your vehicle from up to 50 feet away.

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.

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.

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.

Front doors not locking with fob.
ANSWER : The front door lock actuators are controlled by the their respective door switch units. The rear lock actuators are controlled by the Body Control Module. When the key fob is pressed to lock or unlock. The Body Control Module receives the request and then locks/unlocks rear doors and sends a signal to both the drivers door and passenger front door switch assemblies over a computer data line to lock/unlock front doors. Since the rear door locks are operating, one of two things is happening, either the door lock/unlock request is being interrupted on the computer data line or the Body Control Module is not sending the request to lock/unlock doors to the data line. One way to see if the problem lies with the data line or the Body Control Module is to try to lock or unlock all doors from the driver’s door switch. If the rear doors do not lock/unlock then the data line to the Body Control Module is open and will need to be traced to locate the open circuit and repaired. You may want to enlist the help of a mechanic, like one from YourMechanic who can scope out the data line to see if the signal is being interrupted and to locate and repair the open circuit.

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.

Front Passenger Lock sometimes does not lock with a remote control or by locking button located on either doors.
ANSWER : The solenoid is on the door latch and is most likely the cause of the problem for your 2005 Toyota Tacoma. If you want to have this inspected and repaired, a certified technician from YourMechanic can come to your home or office to diagnose your door lock and perform the correct replacement.

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.

Door lock switch or actuator failure?
ANSWER : The only way to know exactly what is going on with your door locks is with a diagnosis. This should be done with a test light and a wiring diagram. Since the door locks failed in a progression of one or two followed by another, the most likely cause for this would be the actuators in the doors. Door lock actuators is one of the higher failure rate items on Honda’s. Even so, I would have a solid diagnosis done before I replaced them. This will be complicated by the fact that there are so many parts of this system that has failed.

The key fob is likely a problem with the fob itself. It could be a BCM (body control module) problem, but this will require testing to be sure. The fact that you hear a noise when you push the interior switch suggests the switch is working. It is very common for the door lock actuators to freeze up mechanically and still attempt to activate with the electrical portion of the system. The outside door lock can also be stuck as a result of the drivers door actuator becoming completely frozen. It could of course be the lock cylinder itself. The only way to know, again, is to remove the door panels and check for power and ground at the actuators. This will test the master window switch and confirm there is power and ground at the actuators.

Most likely all the door panels will need to be removed, but it is important to point out, this diagnosis will require some for thought before doing any disassembly in order to insure more labor that necessary isn’t done. You most likely have three failures, depending on how you look at it. The door lock actuators, the key fob or BCM and possible a lock cylinder issue. Again, this will require a well thought out plan in order not to confuse what is going on. This is the nature of diagnosing multiple problems with a single system.

If you require assistance with this, I recommend the following inspection. Electrical components aren’t working Be sure to send a note to the technician as to what your exact problem is.

Good luck!