You can test the blower motor on your Ford vehicle by applying power and Ground to it with jumper wires.
In this tutorial, I'll explain how to do this and find out if the blower motor is bad (or not).
NOTE: Although this tutorial is geared towards certain Ford 4.9L, 5.0L, 5.8L vehicles (see the box titled ‘Applies To:’ on the right column), the test procedure (described here) applies to any type of 2 wire blower motor.
Contents of this tutorial:
You can find this tutorial in Spanish here: Cómo Probar El Motor Soplador del AC (4.9L, 5.0L, 5.8L Ford) (at: autotecnico-online.com).
TEST 1: Applying Power To The Blower Motor
The blower motor covered by this tutorial is a two wire motor.
What I mean is that the blower motor connector has 2 wires. One wire feeds it battery power. The other feeds it ground.
In a nutshell and without getting too technical, the battery power the blower motor receives comes from either the blower resistor or directly from the blower switch.
Diagnosing a blower motor problem usually starts by testing the blower motor first and that's the focus of this tutorial.
NOTE: As a safety precaution you should use a fused jumper wire or a power probe to apply battery power to the blower motor. You can make your own fused jumper wire by using an inline fuse holder that you can buy at your local auto parts store and insert a 30 amp fuse into it.
Alright, these are the test steps:
Disconnect the blower motor from its 2-wire electrical connector.
You'll notice that the 2 wires of the engine wiring harness connector (that connects to the blower motor) are an orange with a black stripe (ORG/BLK) wire and a black (BLK) wire.
Connect one end of the fused jumper wire to the blower motor male spade terminal that connects to the ORG/BLK wire of the connector.
Connect the other end of the fused jumper wire to your Ford's car battery positive terminal.
Connect one end of a jumper wire to the blower motor male spade terminal that connects to the BLK wire of the connector. Connect the other end to your Ford's battery negative terminal.
The blower motor should run as you soon as you connect the other end of this jumper wire to your vehicle's car battery negative terminal.
Let's take a look at what your test results mean:
CASE 1: The blower motor ran when you applied battery power and Ground with the jumper wires. This is the correct and expected test result and tells you that your Ford's blower motor is good.
If you're having issues with the blower motor not working it's possible that the blower resistor is bad and needs to be tested. Although it's beyond the scope of this tutorial to test the blower resistor, you have at least eliminated the blower motor as bad.
CASE 2: The blower motor DID NOT run when you applied battery power and Ground with the jumper wires. This test result tells you that the blower motor is bad and needs to be replaced.
The next subheading will show you where you can buy the blower motor and save a few bucks.
Where To Buy The Blower Motor And Save
There's a good chance that you can buy the original Motorcraft blower motor online for a whole lot cheaper than somewhere local.
The following links will help you comparison shop for the blower motor:
Not sure if the blower motors above fit your specific Ford? No problem, the folks at the website will make sure for the parts fits by asking you the specifics of your particular Ford vehicle. If the part doesn't fit, they'll find you the right part.
More Ford 4.9L, 5.0L, 5.8L Tutorials
You can find a complete list of tutorials for 4.9L, 5.0L or 5.8L equipped Fords here: Ford 4.9L, 5.0L, 5.9L Index Of Articles.
Here's a small sample of the tutorials you'll find:
- Manifold Absolute Pressure MAP Sensor Test (Ford 4.9L, 5.0L, 5.8L).
- Ignition Coil Test -No Spark No Start Tests (Ford 4.9L, 5.0L, 5.8L).
- How To Troubleshoot A No Start (Ford 4.9L, 5.0L, 5.8L).
- Testing A Blown Head Gasket (Ford 4.9L, 5.0L, 5.8L).
- How To Test Engine Compression (4.9L, 5.0L, 5.8L).
- How To Test The Ford Mass Air Flow (MAF) Sensor (at: easyautodiagnostics.com).
If this info saved the day, buy me a beer!