When the camshaft position (CMP) sensor fails, it'll usually trigger a DTC P0340 on your 2.4L Dodge or Plymouth minivan.
If you're dealing with a CMP sensor problem or a P0340 code, let me tell you —confirming whether the sensor is actually working or not isn't that hard.
Also, you don't need a scan tool to test it (though if you have one, great —it's a must-have tool). But I'm gonna show you how to check the CMP sensor's output using just a basic multimeter.
And if you'd rather skip the testing and go ahead and slap on a new one, no problem —I'll show you where to get it at a good price.
Contents of this tutorial:
- Common Symptoms Of A Bad CMP Sensor (P0340).
- How The CMP Sensor Works.
- 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: Checking The CMP Signal With A Multimeter.
- TEST 2: Making Sure The CMP Sensor Is Getting 8 Volts.
- TEST 3: Making Sure The CMP Sensor Is Getting Ground.
- More 2.4L Chrysler, Dodge, And Plymouth Minivan Tutorials.
APPLIES TO: This tutorial applies to the following vehicles:
- 2.4L Chrysler Voyager: 2001, 2002.
- 2.4L Dodge Caravan: 2001, 2002.
WIRING DIAGRAMS:
IGNITION SYSTEM TESTS:
- Testing The Crankshaft Position Sensor (1996-2002 2.4L Caravan, Grand Caravan, Voyager, Grand Voyager).
- How To Test The Ignition Coil (1996-2007 2.4L Caravan, Grand Caravan, Voyager, Grand Voyager).
OTHER CMP SENSOR TESTS:
- How To Test The CMP Sensor -P0340 (1996-2000 2.4L Dodge And Plymouth Minivan).
- How To Test The CMP Sensor -P0340 (2003-2007 2.4L Chrysler And Dodge Minivan).
Common Symptoms Of A Bad CMP Sensor (P0340)
When the camshaft position (CMP) sensor on your 2001–2002 2.4L Caravan or Voyager completely kicks the bucket, these are the two things you'll see:
- Engine won't start: No matter how long you crank it, the engine just won't fire up.
- Trouble code P0340: With the sensor dead, the PCM isn't detecting a camshaft signal, so it sets this code and stores it in memory.
Now if the sensor is just starting to fail —not completely dead yet— the symptoms can come and go. Here's what you might notice:
- Engine starts then stalls: The engine may start up normally, then shut off right away. That usually points to a signal that's cutting in and out.
- Check engine light (CEL) illuminated: A failing CMP sensor will cause the CEL to turn on and set a diagnostic trouble code (DTC):
- P0340: No Cam Signal At PCM.
- Erratic Engine Behavior: Things like rough idle, hesitation, random misfires, or poor throttle response (lack of power) are common when the CMP sensor is glitching.
How The CMP Sensor Works
The camshaft position sensor (CMP) on your 2.4L Caravan or Voyager is a Hall-Effect type sensor that needs both power and Ground to operate.
Power comes in the form of 8 Volts DC, and both the power and Ground are supplied directly by the PCM (Powertrain Control Module).
As the camshaft spins (as the engine is cranking or running), the CMP sensor begins generating a pulsed DC voltage signal.
This signal toggles between high (ON) and low (OFF) voltage, and it's one of the key signals the PCM uses to control ignition timing and fuel injection.
- ON: The sensor outputs about 5 Volts.
- OFF: Voltage drops to around 0.3–0.5 Volts.
This ON/OFF voltage pattern helps the PCM track the precise position of the camshaft. Combined with the crankshaft position (CKP) sensor signal, it ensures that spark and fuel are delivered at the exact right time.
When this signal drops out, it's what causes a no-start condition and sets code P0340 in the PCM's memory.
Should I Just Replace The CMP Sensor Without Testing It?
I'll be straight with you —when code P0340 shows up in the PCM's memory, most folks (and even a lot of repair shops) don't bother testing the camshaft position sensor. They just swap it out.
And honestly, that's not a bad move. In the majority of cases, replacing the CMP sensor takes care of the issue —no extra troubleshooting required.
So if you're leaning toward replacing it without doing any tests, that's totally valid. I've added links below where you can buy a replacement CMP sensor from well-known brands —no knockoff stuff— and they'll save you some cash, too.
But... If you're the kind of person who likes to confirm before replacing parts, I've got your back. In this tutorial, I'll show you exactly how to test the sensor with a multimeter and verify whether it's truly causing P0340 or not.
Where To Buy The CMP Sensor And Save
Camshaft Position Sensor Connector Pinout
| CMP Sensor Circuits | ||
|---|---|---|
| Terminal | Wire | Description |
| 1 | Orange (ORG) | 8 Volts DC |
| 2 | Black with light blue stripe (BLK/LT BLU) | Ground |
| 3 | Tan with yellow stripe (TAN/YEL) | CMP Sensor Signal |
TEST 1: Checking The CMP Signal With A Multimeter
To get started, we're gonna check if the camshaft position (CMP) sensor is sending out its expected ON/OFF voltage signal as we turn the engine over manually with a 1/2 inch ratchet and socket on the crankshaft pulley bolt.
Why not use the starter motor? Because the only way to catch the ON/OFF voltage change with a multimeter, is to slowly rotate the engine by hand.
If we use the starter motor, the engine will spin too fast and the signal will flash too quickly for for the multimeter to register it.
If you don't have a multimeter, or thinking about upgrading, here's the one I personally use and recommend: Tekpower TP8268 AC/DC Auto/Manual Range Digital Multimeter (via Amazon).
CAUTION: If you're raising your minivan's front end to reach the crank pulley bolt, always use jack stands. Never trust the jack by itself.
NOTE: Leave the sensor plugged in during the test. To access the signal wire, use either a back probe at the connector or a wire piercing probe directly on the wire. You can see what that tool looks like here: Wire Piercing Probe.
Here's how to check the CKP signal output:
- 1
Disconnect the ignition coil pack from its electrical connector.
IMPORTANT: This step is important as it guarantees the engine doesn't accidentally start during the test. - 2
Set your multimeter to DC Volts mode.
- 3
Connect the black multimeter lead to the battery's negative (-) terminal.
- 4
Probe the TAN/YEL wire at the CMP connector using the red lead.
You can either back probe the connector or use a wire piercing tool on the wire itself. - 5
Slowly rotate the crankshaft pulley clockwise while watching the multimeter.
IMPORTANT: Do not use the starter to crank the engine. You must rotate it by hand to catch the ON/OFF signal with a multimeter. - 6
The voltage should switch between 5V and 0V.
ON is around 5 Volts DC; OFF drops to roughly 0.3–0.5 Volts (which we'll treat as 0V for this test).
IMPORTANT: Rotate the crankshaft pulley at least two full turns to be sure you're capturing the full signal cycle.
Now let's break down what your results mean:
CASE 1: Your multimeter displayed a clear ON/OFF signal. Great news. That confirms the CMP sensor is working and providing a usable signal to the PCM.
This also proves the sensor is getting both power and Ground —without those, there'd be no signal. So if you're chasing code P0340 and you see this signal, the sensor likely isn't the issue.
CASE 2: No ON/OFF voltage showed up at all. Double-check your test setup: lead connections, wire probe contact, etc.
If the signal still doesn't show, then the next step is to verify that the CMP sensor is receiving power. Head over to: TEST 2: Making Sure The CMP Sensor Is Getting 8 Volts.