You don't need a scan tool or fancy equipment to test the camshaft position (CMP) sensor — it's actually a straightforward process.
Armed with a basic multimeter and this step-by-step tutorial, you'll be able to easily and quickly find out if your sensor's working or not.
Whether you're a seasoned DIYer or the weekend warrior-wrenching type, I’ll guide you through how to test the CMP sensor the right way —with clear, easy-to-follow steps.
Contents of this tutorial:
- Symptoms Of A Bad CMP Sensor.
- How The CMP Sensor Functions.
- Should I Just Replace The CMP Sensor Without Testing It?
- Where To Buy The CMP Sensor And Save.
- Camshaft Position Sensor Connector Pinout.
- TEST 1: Testing The CMP Signal With A Multimeter.
- TEST 2: Making Sure The CMP Sensor Is Getting 5 Volts.
- TEST 3: Making Sure The CMP Sensor Is Getting Ground.
- Installing The CMP Sensor: Air Gap Clearance.
- More 3.3L V6 Chrysler, Dodge, And Plymouth Minivan Tutorials.
APPLIES TO: This tutorial applies to the following vehicles:
- 3.3L V6 Chrysler Town & Country: 2004, 2005, 2006, 2007.
- 3.3L V6 Dodge Caravan: 2004, 2005, 2006, 2007.
- 3.3L V6 Dodge Grand Caravan: 2004, 2005, 2006, 2007.
IGNITION SYSTEM TESTS:
- How To Test The CKP Sensor (2004-2007 3.3L V6 Chrysler And Dodge Minivan).
- How To Test The Coil Pack (2001-2008 Chrysler 3.3L, 3.8L) (at: easyautodiagnostics.com).
WIRING DIAGRAM:
OTHER CMP SENSOR TEST TUTORIALS:
- How To Test The CMP Sensor (1990-1993 3.3L V6 Chrysler, Dodge, And Plymouth Minivan).
- How To Test The CMP Sensor (1994-1997 3.3L V6 Chrysler, Dodge, And Plymouth Minivan).
- How To Test The CMP Sensor (1998-2000 3.3L V6 Chrysler, Dodge, And Plymouth Minivan).
- How To Test The CMP Sensor (2001-2003 3.3L V6 Chrysler And Dodge Minivan).
Symptoms Of A Bad CMP Sensor
When the camshaft position (CMP) sensor fails on your 2004–2007 3.3L V6 Chrysler or Dodge minivan, it can trigger the check engine light (CEL) and cause noticeable driveability issues.
Here are the most common signs of a failing CMP sensor:
- Engine cranks but won't start: The engine turns over, but never actually starts and runs.
- Hard to start: It may take longer than usual to get the engine started and running.
- Engine stalls: The engine might die unexpectedly after starting or after it's been running a while.
- Rough or unstable idle: You might notice inconsistent idle speeds or occasional misfiring.
- Lack of power: The engine can feel sluggish or unresponsive under acceleration.
- Diagnostic Trouble Code P0340: This code shows up when the PCM detects a missing or faulty camshaft signal.
How The CMP Sensor Functions
The camshaft position (CMP) sensor used on this engine is a Hall-Effect sensor —which is why its connector has three wires.
It receives an 5-Volt power feed and Ground from the PCM, which are necessary for it to generate its CMP signal.
As the engine rotates, the sensor outputs a digital square wave that switches between 5 Volts and about 0.3–0.5 Volts. This ON/OFF pattern signals the camshaft's position to the PCM.
The PCM depends on this signal pulse to accurately manage ignition timing and fuel injection events. Throughout this tutorial, I'll refer to it as the pulsed or ON/OFF CMP voltage signal.
Should I Just Replace The CMP Sensor Without Testing It?
It's pretty common for both DIYers and even repair shops to go ahead and replace the cam sensor right away —and honestly, that fix works more often than not.
Because the CMP sensor doesn't cost an arm and a leg and quick to change out, swapping it first can sometimes save you the hassle of running tests.
If you're leaning toward replacing it, check the links below for some budget-friendly options —and don't miss:
On the other hand, if you want to be sure the sensor's actually the issue before buying a new one, this tutorial will walk you through the testing process step-by-step.
Where To Buy The CMP Sensor And Save
The following links will help you comparison shop for the camshaft position sensor:
CMP Spacer: Air Gap Spacer
NOTE: If you're installing a new sensor or removing and reinstalling the same one, see: Installing The CMP Sensor: Air Gap Clearance.
Camshaft Position Sensor Connector Pinout
| CMP Sensor Circuits | ||
|---|---|---|
| Terminal | Wire | Description |
| 1 | Pink with yellow stripe (PNK/YEL) | 5 Volts DC |
| 2 | Dark blue with dark green stripe (DK BLU/DK GRN) | Ground |
| 3 | Dark blue with grey stripe (DK BLU/GRY) | CMP Sensor Signal |
TEST 1: Testing The CMP Signal With A Multimeter
We'll kick off our camshaft position sensor check with a basic signal test that'll require turning the engine by hand (not using the starter motor).
This test will let us see whether the CMP sensor is putting out the ON/OFF voltage pulse the PCM needs to control ignition and fuel timing.
Here's the key thing to look for:
- ON: Signal line reads 5 Volts.
- OFF: Signal drops to around 0 Volts.
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 motor during this test — it spins the engine too quickly for your multimeter to pick up the ON/OFF voltage pattern from the sensor.
CAUTION: You might need to lift the minivan to reach the crankshaft pulley bolt. If so, always use jack stands to secure the vehicle — never rely on the jack by itself.
IMPORTANT: The CMP sensor must remain connected to the engine wiring harness connector during this test. You'll need to access the signal wire by back-probing the connector or using a wire-piercing tool. You can check out an example of that tool (and where to buy it) here: Wire Piercing Probe.
Here's are the test steps:
- 1
Unplug the ignition coil pack connector.
IMPORTANT: Always do this first to make sure the engine doesn't accidentally start while you're testing. - 2
Set your multimeter to DC Volts mode.
- 3
Attach the black multimeter lead to the battery's negative (-) terminal.
- 4
Back-probe the dark blue with gray stripe (DK BLU/GRY) wire at the CMP sensor connector or pierce it carefully with a probe tool.
NOTE: The sensor must stay plugged into its engine wiring harness connector while testing the signal. - 5
Turn the key to the ON position (engine off).
- 6
Manually rotate the crankshaft.
Use a socket and ratchet to slowly turn the crankshaft pulley clockwise. - 7
Watch for a clean switch between 5 Volts and around 0.3–0.5 Volts as you turn the pulley.
Here's what those results mean:
CASE 1: You see the ON/OFF voltage switching. That's great —it means the sensor is working like it should.
This confirms the CMP sensor is alive, generating a readable signal, and receiving both its power and Ground. No need for further testing unless another problem is present.
CASE 2: No switching voltage at all. Double-check your connections and verify you're probing the correct wire.
If there's still no signal, the next step is to make sure the sensor is getting its 5 Volt supply from the PCM. Continue to: TEST 2: Making Sure The CMP Sensor Is Getting 5 Volts.