This is a diy on removing replacing and testing the blower motor on a 1995 bmw 740il. it takes about 2 hours to remove test and put it back together.
Tools you will need:
13mm socket
10mm socket
ratchet
t10 torx
t20 torx
t25 torx
flat screwdriver
phillips screwdriver
19mm socket
pliers
volt meter
1) remove the 4--13mm bolts on each end of the dash
2) remove the 4 screws in the top side of the glove box
3) remove the 6 plastic nuts from the trim above the glove box
4) remove the trim on the a pillars
5) remove the 4 t20 screws from the dash there is one on each side of the radio and one on each a pillar
6) pry the passenger side airbag cover and unbolt the passenger side air bag 4--10mm nuts
7) remove the gauge cluster there is 2--t10 screws on the top of it that hold it in
8) remove the headlight and fog light switch pull the knobs off and there is a 19mm plastic nut to remove
you can now take the top of the dash out of the car.
9) there is 2 plastic arms that you have to take off. the top arm unclips from the vent box on both sides. the lower arm pulls out of the vent box on the left side and unclips on the right side.
10) unplug the blower motor and remove the 4--t20 screws from the cover over the blower motor
11) remove the blower motor. there is 3--t25 screws that hold the blower motor in.
if the blower motor is good you should have 1.8 ohm's between the hot and neutral wires ( red and blue). you can also test for voltage at these wires you should have 3.8v when it is starting. the voltage will rise with fan speed. the 3.8 volts is only to start the blower motor.
you can check the resistance on the blower motor resistor also. you should have 1.4ohm's on the hot and neutral pins. you can test the voltage going in to the resistor should be 12 volts. to can test this on the 2 big wires on the plug ( brown is neutral and yellow red is hot) the key must be on and battery connected.
if both check out good (witch this was the problem on mine) you can try to lube the bearings on the blower motor it self.
luge the bearings using a drop of oil or lithium grease. do not over oil the bearing's or you may burn out the blower motor. then test the blower motor before you reinstall it.
you can test it by attaching a wires to the hot and neutral ( red and blue) to a car battery. the red one is the positive and the blue is the negative. you will know right away if it is good or bad.
installation is reverse of the removal. the only problem i had was getting the dash pad back in the foam kept getting in my way.
this saved me some money and glad i did not have to replace either parts. any other question's just ask. this is my first time posting a Diy so let me know if i need to change or add something.
Question
Jeff
This is a diy on removing replacing and testing the blower motor on a 1995 bmw 740il. it takes about 2 hours to remove test and put it back together.
Tools you will need:
13mm socket
10mm socket
ratchet
t10 torx
t20 torx
t25 torx
flat screwdriver
phillips screwdriver
19mm socket
pliers
volt meter
1) remove the 4--13mm bolts on each end of the dash
2) remove the 4 screws in the top side of the glove box
3) remove the 6 plastic nuts from the trim above the glove box
4) remove the trim on the a pillars
5) remove the 4 t20 screws from the dash there is one on each side of the radio and one on each a pillar
6) pry the passenger side airbag cover and unbolt the passenger side air bag 4--10mm nuts
7) remove the gauge cluster there is 2--t10 screws on the top of it that hold it in
8) remove the headlight and fog light switch pull the knobs off and there is a 19mm plastic nut to remove
you can now take the top of the dash out of the car.
9) there is 2 plastic arms that you have to take off. the top arm unclips from the vent box on both sides. the lower arm pulls out of the vent box on the left side and unclips on the right side.
10) unplug the blower motor and remove the 4--t20 screws from the cover over the blower motor
11) remove the blower motor. there is 3--t25 screws that hold the blower motor in.
if the blower motor is good you should have 1.8 ohm's between the hot and neutral wires ( red and blue). you can also test for voltage at these wires you should have 3.8v when it is starting. the voltage will rise with fan speed. the 3.8 volts is only to start the blower motor.
you can check the resistance on the blower motor resistor also. you should have 1.4ohm's on the hot and neutral pins. you can test the voltage going in to the resistor should be 12 volts. to can test this on the 2 big wires on the plug ( brown is neutral and yellow red is hot) the key must be on and battery connected.
if both check out good (witch this was the problem on mine) you can try to lube the bearings on the blower motor it self.
luge the bearings using a drop of oil or lithium grease. do not over oil the bearing's or you may burn out the blower motor. then test the blower motor before you reinstall it.
you can test it by attaching a wires to the hot and neutral ( red and blue) to a car battery. the red one is the positive and the blue is the negative. you will know right away if it is good or bad.
installation is reverse of the removal. the only problem i had was getting the dash pad back in the foam kept getting in my way.
this saved me some money and glad i did not have to replace either parts. any other question's just ask. this is my first time posting a Diy so let me know if i need to change or add something.
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