The crankshaft position (CKP) sensor, which is located near the crankshaft pulley, can be tested with a multimeter. No scan tool needed, and in this article, I'll show you how to do it.
When the crank sensor fails on your Ford Escort (Focus, or Mercury Tracer), the car will crank but not but not start. Along with not starting, you won't see any spark at all from any of the spark plug wires and no fuel injector activation pulses (as checked with a Noid light).
Since quite a few things can cause your Ford vehicle to not start (such as a bad fuel pump, broken timing belt, etc.), it's always a good idea to test the components before replacing them.
Contents of this tutorial:
Important Tips And Suggestions
TIP 1: The crank sensor is located right behind the crankshaft pulley, since the crank sensor's reluctor wheel is behind (and part of) the crank pulley.
TIP 2: The battery in your Ford Escort (Focus, Tracer) must be fully charged. This is important because you'll be measuring the crank sensor's signal while the engine is cranking. A low battery will cause the engine to crank slower than normal and you're not gonna' see a good crank sensor signal result on your multimeter.
TIP 3: You'll need to jack up the vehicle to gain access to the crank sensor. Use a jack stand to hold the car up in the air. Do not trust the jack! Use safety glasses also. Think safety all of the time (your safety is your responsibility).
TIP 4: The first thing you should do, before testing the crank sensor is checking for spark at all four spark plug wires (high tension cables). Why? Well if even just one spark plug cable has spark, this tells you that the crank sensor is OK.
In other words, when the crankshaft position sensor goes bad, you'll get a no-spark no-start condition. So, if you're getting spark, even if in just one cylinder, the crank sensor is good and this test will not help you.
TIP 5: This article does not cover any remove and replace instruction for accesing or replacing the crank sensor. You'll need a repair manual for them (or Google).
Symptoms Of A Bad Ford Crank Sensor
To help you further confirm that the crank sensor is bad, here are couple of things that accompany a bad crank sensor on your Ford 1.9L or 2.0L vehicle:
- Your 1.9L or 2.0L car will crank but not start.
- So if your car starts, the crank sensor is working.
- The PCM (Powertrain Control Module= Fuel Injection Computer) will not pulse any of the 4 fuel injectors.
- No spark coming out of any of the 4 spark plug wires.
- The PCM will not send a switching signal to the coil pack or to all the Coil-On-Plug ignition coils.
TEST 1: Verifying The CKP Signal
The crankshaft position (CKP) sensor test itself is pretty easy, since the sensor is a two-wire type reluctor type.
What is a bit complicated is getting to it, since you'll have to jack up the vehicle (and place it on jack stands) and remove the passenger side wheel to access the sensor.
The following test instructions assume you have already done all of this leg work.
One last thing before we start: If you've got spark coming out of at least one spark plug wire, this tells you that the crank sensor is producing a signal and functioning correctly and this test will not help you.
CAUTION: You'll need to raise the vehicle to access the crankshaft position sensor. After jacking it up, be sure and place it on jack stands. Never trust the jack alone to keep the vehicle up.
NOTE: To connect your multimeter test leads to the CKP sensor's two wires, you're going to need a wire piercing probe. If you don't have one, this is the one that I use and recommend: Goupchn 4mm Banana to Banana Plug Test Leads Kit (Amazon affiliate link).
IMPORTANT: Before you begin, disconnect the ignition coil pack from its connector, or if your vehicle is equipped with individual ignition coils, disconnect all four. This is an important precaution to keep the engine from accidentally starting while performing the CKP sensor test.
OK, this is what you need to do:
- 1
Unplug the crank sensor from its electrical connector and remove some of the plastic wire loom protector and/or the black electrical tape that shields/protects the two wires of the CKP sensor.
- 2
Connect one multimeter test lead to one of the CKP sensor's wires.
It doesn't matter which multimeter test lead (red or black) goes where, since the polarity of the leads doesn't matter. - 3
Connect the other multimeter test lead to the remaining CKP sensor wire.
- 4
Reconnect the connector to the crank sensor.
IMPORTANT: Make sure your multimeter test leads (and wire piercing probes) will not interfere with the crank pulley or the serpentine drive belt, since you'll be cranking the engine. - 5
Set your multimeter to Volts AC mode.
- 6
At this point, with the engine not cranking, you should see 0 Volts AC displayed on your multimeter.
- 7
Have your helper crank the engine (as you observe the multimeter).
- 8
You should see a voltage constantly jumping between 0.5 to 1 Volt AC while the engine is cranking.
To be a bit more specific: your multimeter will not register a steady AC voltage. Instead, the reading will jump between 0.5 Volts AC to 1 Volt AC continually as the engine is cranking and only when the engine is cranking.
OK, let's interpret the multimeter test results you just obtained:
Alright, let's find out if you have a bad CKP sensor on your hands or not. Choose from the CASES below that best match your specific results:
CASE 1: The multimeter registered the indicated AC voltage with the engine cranking. This result indicates that the CKP sensor is creating a good CKP signal and is working fine.
CASE 2: The multimeter DID NOT register the indicated AC voltage with the engine cranking: This confirms that the crank sensor is fried and is the cause of your Ford's 'cranks but does not start condition'.
Where To Buy The Crank Sensor And Save
You can find the crank sensor just about in anywhere. The best place to buy it is is online.
The following links will help you comparison shop for the crank sensor:
Disclosure: As an Amazon Associate, I earn from qualifying purchases. If my tutorials help you, using these links is an easy way to support the site at no extra cost to you. Thank you!
Not sure if the crank sensor fits your particular Ford/Mercury? 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 crank sensor.
Related Articles
You can all of the 1.9L, 2.0L Ford tutorials here: Ford 1.9L, 2.0L Index Of Articles.
Here's a sample of the tutorials you'll find in the index:
- How To Test: Throttle Position Sensor (Ford 1.9L, 2.0L).
- How To Test Engine Compression (Ford 1.9L, 2.0L).
- How To Test Coil Packs (at: easyautodiagnostics.com).
- MAF Sensor Test (in Round Air Filter Canister) (at: easyautodiagnostics.com).
- MAF Sensor Test (at: easyautodiagnostics.com).
If this info saved the day, buy me a beer!
