How To Test a Ford Ranger Crank Sensor

When your Ford truck won’t start or has problems starting, it could be a sign that your Ranger crank sensor has failed. This is a two pin sensor that’s mounted to the front of your 3.0 liter engine, and is a reluctor style unit. This sensor reads the 35 tooth trigger wheel on your crank, and provides the real time positioning and speed of your crank to your engine computer.

As you turn the ignition of your Ranger, the starter will turn the engine. The Ranger crank sensor reads the teeth on your crank plate, and activates the Ignition Control Module or ICM. Based on this signal your engine computer knows how to deliver just the right amount of fuel, and when to active the spark plugs for optimum performance.

If this two pin sensor starts to fail on you, your 3.0 liter Ford Ranger will exhibit some symptoms. Some of the more common Ford Ranger problems include problems with your Ranger having a hard time starting. Today I’ll be showing you how to check a Ford Ranger crank angle sensor in a 2006 with the 3.0 liter engine in it.

One of the more obvious signs of trouble is your check engine light turning on. When you see your Ranger check engine light trigger on, you’ll need a OBDII scan tool to pull out the trouble code.

Codes such as P0320 for Erratic Profile Ignition Pickup or crank angle sensor failure are sure signs that your two pin unit has gone bad. When the Ranger crank sensor in your Ford truck is going out, it can create a dangerous driving condition. When your Ford engine computer sees a lack of signal, it will shut off the engine. If this happens while you are driving you are left without power steering or brake assist. Here’s a few other common Ford Ranger issues when it comes to a failed crank angle sensor.

Signs of a bad Ranger Crank Sensor

• Ranger won’t start
• Long cranking time
• Engine shuts off unexpectedly
• Ignition misfire
• Check Engine Light ON

Your Ford Ranger wont start or shuts off intermittently because there’s no signal from your crank sensor. As the 3.0 liter engine turns, the trigger wheel’s teeth spin past the reluctor style crank angle sensor. This generates a signal through AC voltage that’s used to drive and activate the coil packs and Ranger fuel injectors.

To test your Ford Ranger crank sensor, we’ll be measuring for the internal resistance at the two wires. But in order to do this you will need to locate the sensor, which is mounted to the front of your engine and the wiring loom that connects to it.

Testing your Ranger Crank Sensor

When you need to test your Ranger crank angle sensor, you’ll need to find the wiring connector that leads down to the front of your engine. There are two wires going to the crank angle sensor, and you’ll be using a digital multimeter to test the signal.

Now take your multimeter leads and pierce the crank angle sensor wires. You will need to carefully cut away electrical sheathing or remove electrical tape to get at the wires.

You don’t need to worry about which lead goes to what. Because this Ranger crank sensor is a reluctor type, there’s no preference as to which wire should be pierced by which multimeter lead.

Once you’ve got both of your multimeter leads pierced into both crank angle sensor wires, you can begin the test. Make sure to pierce the section of wire that is furthest away from your 3.0 liter Ford engine. Keep your hands, tools and clothing free and clear from your engine bay as much as possible and make especially sure to avoid the cooling fans and drive belts.

Now that you are free and safe from your engine, have a friend make sure that your transmission is in neutral or park, and that your parking brake is engaged.

Now turn the dial of your digital multimeter to read in AC voltage. Have your friend crank the engine while you observe the voltage at the Ranger crank sensor.

If your Ranger crank sensor is still working correctly, you should see your multimeter jump in voltage between .5 to 1 Volt AC.

It should not read a solid value but instead oscillate between .5 Volts AC to 1 Volt AC as the sensor reads the teeth on your crankshaft pickup plate. This means that your crank angle sensor is working correctly.

If your crank angle sensor issues, or your Ford Ranger truck seems to turn off when the engine is hot this is a common issue. Turn on your engine and allow it to warm up, or until your cooling fans trigger on. At this point you can recheck the crank angle sensor using our test.

When your Ford Ranger crank angle sensor does not respond in the right manner, it’s a clear sign that the unit has died. Remove the bad sensor and install a replacement, and don’t forget to use your OBDII scan tool to clear any lingering check engine lights.

Have any questions about this Ford Ranger crank sensor tutorial? Leave us a comment below and let us know!