How to Test the Blower Motor (Ford 4.0L)

Your Ford Explorer's (Aerostar, Ranger, B4000, Mountaineer, Mountaineer) blower motor is a simple 2-wire component that can be easily tested by manually applying battery power and ground to it.

If your 4.0L Ford Explorer (Aerostar, Ranger, B4000, Mountaineer, Mountaineer) is currently experiencing a ‘no blower’ problem, then there's a good chance that the blower motor has fried and needs to be replaced.

In this tutorial I'll show you how to test it and find out for sure.

NOTE: This tutorial covers the vehicles in the box titled ‘Applies To:’ on the right column. But, the test procedure (described here) applies to any type of Ford blower motor that has a two-wire connector.

Here are the contents of this tutorial at a quick glance:

  1. TEST 1: Applying Power and Ground to the Blower Motor.
  2. Where to Buy the Blower Motor and Save.
  3. More Ford 4.0L Diagnostic Tutorials.

En EspaƱol You can find this tutorial in Spanish here: Verificando el Motor del Soplador del Aire Acondicionado (4.0L Ford) (at: autotecnico-online.com).

TEST 1: Applying Power and Ground to the Blower Motor

Applying Power and Ground to the Blower Motor. How to Test the Blower Motor (Ford 4.0L)

The blower motor gets power and ground from the 2 wires that connect to it.

The connector on your Ford's blower motor will have a BRN/ORG wire and a PNK/WHT wire.

What we'll do, to check to see if the blower motor is fried is to unplug the blower motor from its connector and manually apply battery power and ground with jumper wires or a power probe.

By the way, the original blower motor on your 4.0L Ford Explorer (Aerostar, Ranger, B4000, Mountaineer) may not look exactly like the one in the image viewer. Don't worry, since the only difference will be that one has the plug (where the harness connector connects to) right on the body of the motor and the other has the plug on two extended wires.

NOTE: If you use a jumper wire, make your own fused jumper wire to apply battery power to the blower motor (as a safety precaution against shorting the jumper wire to ground). 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:

  1. 1

    Disconnect the blower motor from its two-wire electrical harness connector.

  2. 2

    Connect one end of the fused jumper wire to the blower motor male spade terminal labeled with the number 1 (in the illustration).

    Connect the other end of the fused jumper wire to your Ford's car battery positive terminal.

  3. 3

    Connect one end of a jumper wire to the blower motor male spade terminal labeled with the number 2.

    Connect the other end of the jumper wire 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. This tells you that the blower motor is good and not the cause of the ‘no blower’ problem your Ford Explorer (Aerostar, Ranger, B4000, Mountaineer) is experiencing.

There's a good chance that what's causing the ‘no blower’ problem on your Ford is a bad blower resistor or a bad blower switch. Altho' it's beyond the scope of this tutorial to diagnose these components... 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

You can find the blower motor in any auto parts store. If you're wanting the buy the original Ford Motorcraft blower motor, you can buy it online for a whole lot cheaper than somewhere local.

The following links will help you comparison shop for the Ford Motorcraft and after-market blower motors:

Will the above blower motor fit your particular Ford Explorer (Aerostar, Ranger, B4000, Mountaineer)? Don't worry, once you get to the site they'll make sure it fits (by asking you the specifics of your particular Ford vehicle). If it doesn't fit, they'll find you the right one.

More Ford 4.0L Tutorials

You can find a complete list of 4.0L Ford troubleshooting tutorials here: Ford 4.0L Index of Articles.

Here's a sample of the tutorials you'll find in the index:

  1. How to Test the Fuel Pump (Ford 4.0L Aerostar, Ranger, Explorer).
  2. How to Test Engine Compression (Ford 4.0L).
  3. How to Troubleshoot a No Start (Ford 4.0L).
  4. How to Test the Fuel Injectors (Ford 4.0L).
  5. How to Test the Ford EGR Valve EGR Vacuum Solenoid, DPFE Sensor (at: easyautodiagnostics.com).
  6. How to Test the Coil Pack (Ford 3.0L, 3.8L, 4.0L, 4.2L) (at: easyautodiagnostics.com).