The blower motor on my van is running at 1/2 speed when it is in the 3/4 position. High works as it should. Would this be a sign of a bad switch or resistor, or is there a way to tell? To be more specific. 1/4 speed works as it should, 1/2 is faster than 1/4, and there is no difference between 1/2 and 3/4. Thanks!
Blower motor switch or resistor?
- Thread starter nwjones18
- Start date
- Status
I had the same problem in my Dakota. I had a pretty low output on my high fan speed and really no difference in the amount of air flow between the highest fan speed and the next lowest speed. A new blower motor resistor pack fixed it. I don't know about Fords but blower motor resistor failure is a very common problem on Dodges.
This is difficult to answer without knowing the motor type and drive. I'd think resistors would no longer be used cause there are cheaper more efficient and more reliable ways to vary motor speed than via a switchable resistance in series with motor power. For example, PWM drives are much more robust, when properly designed. If you found a motor spec and a drive ckt schematic we could figure it out.
Originally Posted By: digitalSniperX1
This is difficult to answer without knowing the motor type and drive. I'd think resistors would no longer be used cause there are cheaper more efficient and more reliable ways to vary motor speed than via a switchable resistance in series with motor power. For example, PWM drives are much more robust, when properly designed. If you found a motor spec and a drive ckt schematic we could figure it out.
Sorry. Its a 1999 E150 with the 4.6. Front blower that's having the problem. It has a resistor like this one.
http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Blower-Motor-Resistor-BWD_10017337-P_861_R|GRPSESWAMS_____#
This is difficult to answer without knowing the motor type and drive. I'd think resistors would no longer be used cause there are cheaper more efficient and more reliable ways to vary motor speed than via a switchable resistance in series with motor power. For example, PWM drives are much more robust, when properly designed. If you found a motor spec and a drive ckt schematic we could figure it out.
Sorry. Its a 1999 E150 with the 4.6. Front blower that's having the problem. It has a resistor like this one.
http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Blower-Motor-Resistor-BWD_10017337-P_861_R|GRPSESWAMS_____#
Last edited:
I had a problem like this and I replaced the resistor and the problem was solved.
I bought in Rockauto for about $12 and it took about 30 min to install.
They can be hard to reach but there are usually a couple of screws holding them in or sometime even a snap out.
I bought in Rockauto for about $12 and it took about 30 min to install.
They can be hard to reach but there are usually a couple of screws holding them in or sometime even a snap out.
It sounds like speeds 2 and 3 are shorted together. It could be the resistor the control or a burnt harness. You could test it with a volt meter or test light. The black wire at the resistor goes to chassis ground for low speed, the red/orange wire comes from the second switch position, the blue/orange is the third position, and the orange/black goes to the motor.
the resisters and the plugs that plug into them fail more often than the switch
I had the same problem with my Ranger. The lowest setting didn't work; it just blew the same speed as the next highest setting. A new resistor fixed it.
If a fan goes out, the resistor pack can puke. it over hearts. It needs airflow to keep things right.
But most likely, the resistor pack is bad. It the first thing any mechanic would check. They are usually easily accessible.
But most likely, the resistor pack is bad. It the first thing any mechanic would check. They are usually easily accessible.
- Status
Similar threads
