How To Test The Crank Sensor (Chrysler 2.0L, 2.4L)

This tutorial will help you to test the crankshaft position sensor on the Chrysler, Dodge, Eagle, Plymouth, 2.0L (SOHC and DOHC) and 2.4L (DOHC) 4 cylinder equipped cars and mini-vans.

This article covers vehicles from Chrysler, Dodge, Eagle, Mitsubishi and Plymouth. To see if this article applies to your specific vehicle, look for the box (on the column on the right) titled ‘Applies To:’, and click on the ‘next >>’ link to scroll.

Now, since the crankshaft position (CKP) sensor can not be tested by a simple resistance test (multimeter in Ohms mode) off of the car, I'm gonna' show you how to test it dynamically (in action) and on the car. This is a simple multimeter test done in Volts DC mode and I'll walk you thru' the whole thing step by step.

You can find this tutorial in Spanish here: Cómo Probar El Sensor De La Posición Del Cigüeñal (Chrysler 2.0L, 2.4L) (at: autotecnico-online.com).

Symptoms Of A Bad Crank Sensor

When the crankshaft position sensor (CKP sensor) goes bad on your Chrysler 2.0L, 2.4L -the most obvious symptoms will be that your car is not gonna' start. It will crank but not start.

Here are some more specific symptoms of a bad crankshaft position sensor:

1. The Auto Shutdown Relay does not activate and thus does not provide power to:
   • The fuel injectors.
   • The ignition coil pack.
   • The fuel pump relay and thus the fuel pump.
2. No spark firing from all of the spark plugs.
3. Fuel pump does not activate during cranking.
4. The PCM (Powertrain Control Module = Fuel Injection Computer) does not activate the fuel injectors.

The two most important symptoms to look for are no spark from all of the spark plug wires and no fuel injector pulses from all of the fuel injector connectors (as tested by a Noid light).

If you have spark, even if it's just from one spark plug wire or fuel injector pulses, the crankshaft position sensor is not bad.

Tools You'll Need To Test The 2.0L, 2.4L Crank Sensor

You don't need any expensive tools to test the crankshaft position sensor on your 2.0L, 2.4L engine. As a matter of fact, you don't even need a scan tool to test it.

Tools you'll need to test the crankshaft position sensor on your car (or mini-van):

1. Multimeter.
   • You can use a digital multimeter or an analog multimeter although the digital one is the preferred one.
   • If you don't have a multimeter or need to upgrade yours, check out my recommendation here: Buying A Digital Multimeter For Automotive Diagnostic Testing (at: easyautodiagnostics.com).
2. Jack
3. Jack stands
4. 1/2 inch ratchet wrench and the necessary sockets to turn the crank pulley.

As you see, the tools you'll need won't break the bank and more than likely you already own most of them.

How The Crank Sensor Works

The crankshaft position sensor, on your Chrysler 2.0L/2.4L equipped car or mini-van, is a Hall-Effect three wire crankshaft position sensor.

Since the crankshaft position sensor is a Hall Effect type sensor, it produces an ON/OFF DC voltage signal that can be easily measured with:

• A multimeter.
• An oscilloscope.
• Or an LED Light.

This also means that there is no crankshaft position sensor resistance test to see if the crankshaft position sensor is bad or not. Only the 2 wire reluctor type crankshaft position sensor can be resistance tested.

As you turn the key and crank the engine, each one of the three wires that connect to the crankshaft position sensor have a specific job to do:

1. One delivers power in the form of 5 or 8 Volts from the PCM.
   • This thru' the wire labeled with the number 3.
2. Another delivers Ground. This Ground is provided inside the PCM, too.
   • This thru' the wire labeled with the number 2.
3. The last remaining, delivers the signal, that the CKP sensor creates, to the PCM.
   • This thru' the wire labeled with the number 1.
4. The PCM uses the crank signal to activate the Auto Shut Down (ASD) Relay.
5. The Auto Shut Down (ASD) Relay activates:
   • The fuel pump relay and thus the fuel pump.
   • The fuel injectors.
   • The ignition coil pack and thus spark to each engine cylinder.
6. Therefore, the crankshaft position sensor (and its signal) is critical for the engine to start.

The most important thing to know, is that if the crankshaft position sensor goes bad, your Chrysler (or Dodge or Plymouth or Eagle) vehicle will crank but not start due to a lack of spark and fuel injection.