My 1999 BMW blower comes on whenever I put keys in the switch and turn the motor on.
My 1999 BMW blower of the AC or heater comes on whenever I put keys in the switch and turn the motor on.
My car has 270000 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hi there, thanks for writing in. If this comes on right when the car is turned on, then most of the time it is caused by a bad blower resistor module. This module fails internally and causes this to occur. I usually test the module first to see if it has failed as it can also be the fan control from the HVAC module. If you want to have this blower motor problem fixed, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
The blower motor controls the airflow for the heating and cooling system; it is one of the main components for the HVAC system to operate properly.
In most cases, a blower motor resistor fails due to corrosion or overheating. Sometimes, the mechanical resistance to the motor rotation causes an excessive electric current that can overheat and prematurely damage the blower motor resistor.
Since it directly contributes to airflow, a bad blower motor resistor will affect your HVAC system`s ability to both heat up AND cool down. If your fan seems to work properly, the speed settings function, and air is moving fine, but it`s just not getting cold, then you may have a bad heater core.
The fan setting on your thermostat controls your HVAC`s system blower. The blower helps circulate hot or cold air throughout your home until the temperature on the thermostat is reached. There are two settings on your thermostat to control the fan – auto or on.
Lack of maintenance: This is probably the most common reason that causes condenser fan motors to overheat and shut off. Proper and regular lubrication of the fan motor is necessary for the motor to run smoothly. Periodically making sure that there`s no debris or dust in or around the fan motor is also a good idea.
You may have a dirty air filter problem. When the air filter restricts airflow, the evaporator coil can become frozen, causing the unit to turn on and off. As a reminder, air filters should be replaced at least once a month. You may do this more often if you are constantly running your air in the summer.
Here`s an easy way to test if the fan`s capacitor is bad.
If the fan takes off and then keeps going on its own, you more than likely have a bad start capacitor. You took over its job of kick-starting the fan by pushing the blades. If the fan doesn`t start running, you may have a bad fan motor.
If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed. The heating and air conditioning systems may still function at one speed, however the resistor will have to be replaced in order for full functionality to be restored.
One of the first symptoms of a problem with the blower motor relay is a blower motor that does not function. As the relay is the switch that supplies current to the blower motor, if it fails internally, then power may be cut off from the blower motor circuit causing the motor to no longer function.
The blower motor resistor is responsible for controlling the blower motor speed. In the past, this was done by varying the voltage supplied to the blower motor. In newer applications, the blower motor resistor is actually a solid state module that sends a varied signal to the blower motor.
The blower motor resistor in your car is the part that is responsible for pushing air through the vents when using the air conditioner or heater.
If little air is coming through the vents (hot or cold), then it could be because the blower motor for the fan or a switch or resistor that controls fan speed isn`t working. Another cause might be that the electronically controlled “blend doors” that direct air flow are stuck or broken.
The fan speed can be changed by switching the blower resistor resistance mechanically, using a rotating lever, or electronically by the air conditioning system. The blower motor resistor is responsible for controlling the blower motor speed.
The green wire underneath your thermostat connects to the fan of your furnace or air handler. It terminates at the air handler or furnace. The green wire connects to terminal G on your thermostat.
The blower motor is an important part of your vehicle`s heat and air conditioning systems. Without it, you can`t control the temperature of your cabin — not a dire consequence, but definitely a major annoyance in extreme heat or cold.
What is a blower motor? This is the part in your air conditioning system that controls the operation of your AC system and regulates the temperature in your vehicle.
Your AC is rendered useless without a functioning fan or furnace blower motor. This could also mean that you need a furnace repair or should start looking at costs for blower motor replacement. In addition, you will either suffer from no air or weak airflow with fan problems.
The blower motor is a component in your HVAC system that blows the conditioned air through the vents in your home. It takes the cool air that your air conditioner makes and circulates it throughout your house. The blower circulates the air to ensure that the temperature reaches the level dictated by your thermostat.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
My 1999 BMW blower comes on whenever I put keys in the switch and turn the motor on.
ANSWER : Hi there, thanks for writing in. If this comes on right when the car is turned on, then most of the time it is caused by a bad blower resistor module. This module fails internally and causes this to occur. I usually test the module first to see if it has failed as it can also be the fan control from the HVAC module. If you want to have this blower motor problem fixed, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.
Put key in ignition. Lights and everything come on for a second, then went off as I turned the key. Now no power, key stuck
ANSWER : Hi, thanks for writing in. This sounds like your battery cable connections are corroded or loose at the battery. Try to see if the battery connections are loose by wiggling them and see if power returns. If power returns, then have the cables removed, cleaned, and reconnected to test the battery. Hope this helps and best of luck!
If I replace the ignition switch, can I use my existing BMW Keys with remote and valet key?
ANSWER : Yes, you can. The ignition switch is separate from the EWS system, so replacing the switch will still allow you to use the current keys you already have. Only if you have to replace a faulty key or EWS module will you have to possibly order all new keys.
One other possibility is there is an EWS issue where the key is not being properly identified not allowing the starting sequence. This would mean ordering an EWS module or keys from the dealer. Try out all keys you have to see if any will commence in the starting sequence. If none of the keys will start the vehicle, faults should be checked to ensure there are no EWS key identification faults. If no faults are present, then most likely the ignition switch is faulty. If there are key identification faults, then it’s either a key, module, or receiver that is the issue. You may want to consult with a mechanic who has the equipment to read out the Powertrain and EWS fault memories before replacing parts.
Front A/C blower motor working incorrectly.
ANSWER : One sure way to rule out the blower motor itself would be to observe voltage while the issue is happening. If the voltage being fed to the blower motor fluctuates, the problem is on the control side of the circuit and possibly the resistor. Hire one of our mobile experts to swing by and test the electrical system and track down this bug.
Why does my brake/abs lights come on when I turn on my blower in my 2006 Chevrolet Silverado
ANSWER : Hello. It sounds like you have a voltage issue. When the power in the vehicle drops below a certain level these lights will come on as a warning. Since they come on when turning on the blower that means that the blower is drawing just enough power to cause a drop which is turning these other warning lights on. It may be due to a failing battery, alternator or maybe a bad connection. These would all have to be tested to find the issue. If you are going to have this electrical issue checked, consider YourMechanic, as a certified mechanic can come to you to [diagnose why the abs and brake lights are coming on] https://www.yourmechanic.com/services/abs-light-is-on-inspection
key in accessory position and can’ turn off or on can’t get key to turn stuck in accessory position
ANSWER : Hi and thanks for contacting YourMechanic. When the key is in the ignition switch, the key should not be able to come out of the switch when it has been turned. When the key is able to come out of the ignition switch in the On position or Accessory position, then the lock inside the tumbler has failed. Try to turn the steering wheel side to side to see if the steering wheel lock is causing your issues. If your steering wheel lock is not the issue, then you will need to have a new ignition switch tumbler installed and you will have to get a new key that matches the vehicle. If your ignition switch is stuck in the accessory position and will not shut off the power to the car, you can put graphite into the tumbler to help with the key; although this will damage the tumbler, you will be able to shut off the power to the vehicle. I recommend replacing the ignition switch and key to solve your stuck-in-accessory position situation. If you need assistance in getting your vehicle’s ignition switch to shut off, you should contact a technician. A YourMechanic certified mechanic can come to your location to perform an Ignition key is stuck and does not turn Inspection on your vehicle and diagnose this issue.
Electrical problems, can’t turn off the vehicle
ANSWER : Hello. From what you describe it would appear that you may have a damaged ignition lock cylinder. Virtually all ignition cylinders are designed to keep prevent you from removing the key if the transmission is not in park. If you were able to remove the key then that may be a sign that the ignition lock cylinder is broken or damaged, which could be why it is loose and making a clicking noise. As the ignition lock cylinder is directly connected to the electronic ignition switch, the component that controls power to the vehicle’s electronics and starting system, an issue with it can result in electrical problems with the vehicle. To restore proper functionality to the vehicle I would recommend a proper diagnosis and replacement of the ignition lock cylinder.
Okay I walked outside to put the key in to turn over the car. All lights come on and off but the brake light stays on and flashes when I turn over
ANSWER : Hello, thanks for writing in. Most of the time this is caused by a bad connection. It can be at the battery, the fuse box, or at the starter. From my experience with this vehicle the most common spot is at the starter. I typically check the connections at all three of these spots first before going any further with the diagnosis as an ignition switch can also cause this. If you are planning on having this starting issue fixed, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.
