How To Test The CKP Sensor (1998-2000 3.3L V6 Chrysler, Dodge, And Plymouth Minivan)

The crankshaft position (CKP) sensor can be tested to see if it's actually generating a signal —you don't have to guess or assume it's bad just because a CKP diagnostic trouble code (DTC) has been set.

The test is simple and only requires a multimeter and a bit of your time —no need for high-end diagnostic tools.

In this tutorial, I'll walk you through each step clearly and simply, so whether you're a seasoned tech or just wrenching on weekends, you'll know exactly what to do and how to interpret your results.

And if you'd rather skip straight to replacing the sensor, no problem —I'll also show you where to grab a new one without overpaying for it.

APPLIES TO: This tutorial applies to the following vehicles:

• 3.3L V6 Chrysler Town & Country: 1998, 1999, 2000.
• 3.3L V6 Chrysler Voyager: 2000.
• 3.3L V6 Dodge Caravan: 1998, 1999, 2000.
• 3.3L V6 Dodge Grand Caravan: 1998, 1999, 2000.
• 3.3L V6 Plymouth Voyager: 1998, 1999, 2000.
• 3.3L V6 Plymouth Grand Voyager: 1998, 1999, 2000.

WIRING DIAGRAMS:

• Ignition System Wiring Diagram (1998-1999 3.3L Chrysler, Dodge, And Plymouth Minivan).
• Ignition System Wiring Diagram (2000 3.3L Chrysler, Dodge, And Plymouth Minivan).

IGNITION SYSTEM TESTS:

• How To Test The CMP Sensor (1998-2000 3.3L V6 Chrysler, Dodge, And Plymouth Minivan).
• How To Test The Coil Pack (1990-1998 Chrysler 3.3L, 3.8L) (at: easyautodiagnostics.com).
• 1999-2001 Coil Pack Diagnostic Tests (Chrysler 3.3L) (at: easyautodiagnostics.com).

Symptoms Of A Bad CKP Sensor

On the 3.3L V6 engines used in the Dodge, Chrysler, and Plymouth minivans, the crankshaft position (CKP) sensor (along with the CMP sensor) is used to get the engine started and to keep it running.

So, when it fails, you're gonna see one or more of the following issues:

• Engine won't start: The starter motor cranks the engine, but it doesn't actually start and run.
• Hard start: The engine may take several seconds before it starts (extended engine cranking).
• Sudden stalling: The engine might quit unexpectedly, either at idle or while driving.
• Unstable idle: Idle speed may surge or drop without warning.
• Lack of power: A CKP sensor that is failing, but hasn't completed died yet, will cause reduced engine power or sluggish performance.
• CKP sensor diagnostic trouble code (DTC): The PCM will usually store the following DTC:
  • Code P0320: PCM Not Receiving Crankshaft Signal.

How The CKP Sensor Functions

As you probably already know, the CKP sensor is a 3-wire sensor. This makes it a Hall-Effect type, which requires both power (8 Volts) and Ground to generate its signal.

These are the key points to keep in mind:

• The sensor only produces this ON/OFF voltage pulse when the engine is rotating —like when you're cranking it or the engine is running.
• It creates this pulse by reading the slots cut into the flywheel as they pass in front of the sensor.
• The flywheel has 12 of these slots, so during one full turn of the crankshaft, the sensor will produce 12 ON (5V) pulses and 12 OFF (0V) dips.
  • This voltage pulse flips between 5 Volts and about 0 Volts is what signals the PCM the crankshaft's position.
• This ON/OFF signal works together with the CMP signal from the camshaft position sensor to help the PCM control spark timing and fuel injection to get the engine started and running.

In case you're wondering, the CKP sensor is mounted on the transaxle's bellhousing —right where the bellhousing meets the engine block on the rear side of the transmission (the side facing the firewall).

Should I Just Replace The CKP Sensor Without Testing It?

I think the most common approach to resolving a CKP sensor issue or diagnostic trouble code is to simply swap it out for a new one without doing any testing.

And I tell you what —in most cases, this solves the issue and the minivan's back on the road easy-peasy.

This strategy makes total sense for two reasons:

1. The CKP sensor is a relatively low-cost part and doesn't take long to change.
2. With the sensor crammed into such a tight space, hooking up the multimeter test leads can be quite the challenge —so for a lot of folks its easier to skip testing it and just swap it out for a new one.

If you're going that route, use the links below to find a good deal —and be sure to check this out as well:

• Installing The CKP Sensor: Setting The Correct Air Gap.

But if you'd rather verify the CKP sensor is the issue before spending money, no worries —the step-by-step tests I'm gonna walk you through in this tutorial will show you how.

Where To Buy The CKP Sensor And Save

The following links will help you comparison shop for the crankshaft position sensor:

CKP Spacer: Air Gap Spacer

NOTE: If you're installing a new sensor or removing and reinstalling the same one, see: Installing The CKP Sensor: Setting The Correct Air Gap.

Crankshaft Position Sensor Connector Pinout

CKP Sensor Circuits
Terminal	Wire	Description
1	Orange (ORG)	8 Volts DC
2	Black with light blue stripe (BLK/LT BLU)	Ground
3	Grey with black stripe (GRY/BLK)	CKP Sensor Signal

TEST 1: Testing The CKP Signal With A Multimeter

We'll start off by checking that the crankshaft position sensor is producing an ON/OFF voltage signal by rotating the engine manually —no-starter motor involved.

Here are the specifics of this ON/OFF signal:

• ON: Signal hits 5 Volts.
• OFF: Drops to 0 Volts.

This ON/OFF voltage signal is sent to the PCM through the grey with black stripe (GRY/BLK) wire and it's the one we'll tap into for the CKP signal check.

If you don't have a multimeter or need to upgrade yours? This is the one I use and recommend: Tekpower TP8268 AC/DC Auto/Manual Range Digital Multimeter (at: amazon.com).

NOTE: Don't use the starter to rotate the engine —it'll spin the engine too fast for your multimeter to catch the signal changes. You'll need to use a ratchet and socket on the crankshaft pulley to slowly turn the engine by hand and see the ON/OFF voltage pulses on the multimeter.

CAUTION: You may need to raise the front of your minivan to reach the crankshaft pulley bolt with your ratchet. If so, use jack stands —don't trust the jack alone.

IMPORTANT: The CKP sensor must stay connected to its engine wiring harness connector during this test. Probe the signal wire using a back-probe (on the connector) or a wire-piercing probe (on the wire). You can check out an example of this tool (and where to buy it) here: Wire Piercing Probe.

These are the CKP signal test steps:

1. 1

   Unplug the ignition coil pack.
   
   NOTE: This is an important safety precaution that'll prevent the engine from accidentally starting up.

2. 2

   Switch the multimeter to Volts DC mode.

3. 3

   Connect the black lead to battery negative (-) post.

4. 4

   Probe the CKP signal wire (GRY/BLK) with the red multimeter lead using either a back probe on the connector or a wiring piercing probe on the wire.
   
   NOTE: Keep the CKP sensor connected to the engine wiring harness connector.

5. 5

   Turn the key to the ON position (but engine OFF).

6. 6

   Slowly turn the crankshaft pulley with a ratchet and socket.
   
   NOTE: Don't use the starter motor.
   
   IMPORTANT: Make sure to complete at least one full revolution of the crankshaft so the sensor passes by all the flywheel slots.

7. 7

   You should see the signal voltage flipping between 5V and 0V.
   
   0.3–0.5V equals 0 Volts.
   
   NOTE: You should see the voltage switch 12 times from 5V to 0V as the crankshaft makes one full rotation.

Let's break down what your test result tells us:

CASE 1: You see a switching ON/OFF signal. This is the correct result and confirms that the CKP sensor is working and sending a proper pulse to the PCM.

This also confirms that the CKP sensor is receiving power (8 Volts) and Ground from the PCM. We don't need to continue with any other CKP sensor test.

CASE 2: No switching seen. Recheck your test connections and repeat the test.

If your multimeter still doesn't see an ON/OFF voltage pulse, we need to move on to: TEST 2: Confirming the 8 Volt Supply to the CKP Sensor.