The crankshaft position (CKP) sensor plays a crucial role in keeping your engine running —and the good news is, you can test it yourself using a basic multimeter.
No scan tool required, no need to haul your minivan to a shop. In this tutorial, I'll show you how to diagnose the CKP sensor step by step.
It's quick, easy, and totally doable whether you're a pro wrencher or just diving into DIY repairs.
If you're planning to replace the sensor anyway, I'll also show you where to get a solid deal on a new one.
Contents of this tutorial:
- Symptoms Of A Bad CKP Sensor.
- How The CKP Sensor Functions.
- Should I Just Replace The CKP Sensor Without Testing It?
- Where To Buy The CKP Sensor And Save.
- Crankshaft Position Sensor Connector Pinout.
- TEST 1: Testing The CKP Signal With A Multimeter.
- TEST 2: Making Sure The CKP Sensor Is Getting 8 Volts.
- TEST 3: Making Sure The CKP Sensor Is Getting Ground.
- 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: 2001, 2002, 2003.
- 3.3L V6 Chrysler Voyager: 2001, 2002, 2003.
- 3.3L V6 Dodge Caravan: 2001, 2002, 2003.
- 3.3L V6 Dodge Grand Caravan: 2001, 2002, 2003.
WIRING DIAGRAMS:
- Ignition System Wiring Diagram (2001-2003 3.3L Chrysler And Dodge Minivan).
- Ignition System Wiring Diagram (2004-2007 3.3L V6 Chrysler And Dodge Minivan).
IGNITION SYSTEM TESTS:
- How To Test The CMP Sensor (2001-2003 3.3L V6 Chrysler And Dodge Minivan).
- 1999-2001 Coil Pack Diagnostic Tests (Chrysler 3.3L) (at: easyautodiagnostics.com).
- How To Test The Coil Pack (2001-2008 Chrysler 3.3L, 3.8L) (at: easyautodiagnostics.com).
OTHER CKP SENSOR TEST TUTORIALS:
- How To Test The CKP Sensor (1990-1993 3.3L V6 Chrysler, Dodge, And Plymouth Minivan).
- How To Test The CKP Sensor (1994-1997 3.3L V6 Chrysler, Dodge, And Plymouth Minivan).
- How To Test The CKP Sensor (1998-2000 3.3L V6 Chrysler, Dodge, And Plymouth Minivan).
- How To Test The CKP Sensor (2004-2007 3.3L V6 Chrysler And Dodge Minivan).
Symptoms Of A Bad CKP Sensor
The CKP sensor, along with the CMP sensor, is a key component of the ignition system that's needed by the PCM to start and keep the engine running.
When it fails, you'll see one or more of the following issues:
- Engine no-start condition: The engine cranks normally but never starts.
- Hard start: You've got to crank the engine a long time before it fires up.
- Random engine shutdowns: The engine stalls out of nowhere.
- Unstable idle: Surging, stumbling, or occasional misfires at idle.
- Lack of power: The engine may hesitate or feel like it's got no power.
- CKP sensor diagnostic trouble code (DTC): When the crank signal is lost, you may see this code registered in the PCM's memory:
- P0320: No Crank Reference Signal At PCM.
How The CKP Sensor Functions
The CKP sensor on your minivan is a 3-wire type —which tells us it's a Hall-Effect sensor that needs both power and Ground to produce its signal.
On the 2001–2003 models, it gets a steady 8-volt supply. On the 2004–2007 models, that voltage drops to 5 Volts instead.
Along with that power supply, it also gets a Ground —both are delivered straight from the PCM.
Here are a couple of things to keep in mind:
- The CKP signal is only produced when the engine is spinning —either during cranking or while it's running.
- It does this by detecting the slots machined into the flywheel as they move past 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.
- That switching between 5 and 0 Volts is what lets the PCM "see" the crankshaft's movement and position.
- The ON/OFF CKP signal works alongside the CMP sensor signal, giving the PCM the info it needs to control spark and fuel timing precisely to start and keep the engine running.
You'll find the CKP sensor mounted on the transmission bellhousing —right where it bolts to the engine block, on the backside near the firewall.
Should I Just Replace The CKP Sensor Without Testing It?
What most folks usually do when a CKP sensor code pops up is just replace the sensor without doing any testing.
And honestly, that works out just fine in the majority of cases a CKP sensor diagnostic trouble codes (DTC) pops up —the sensor gets swapped, the problem goes away, and the minivan's back on the road like nothing ever happened.
This strategy makes sense for two main reasons:
- The part's not that expensive, and it doesn't take long to install.
- Because of where it’s located —tight spot, limited room— getting your test leads in place can be a pain in the neck. So for a lot of folks, it’s just easier to replace it than mess with testing.
If you're leaning that way, check out the links below —you'll find a good deal and save a few bucks.
But if you'd rather test the sensor first and be sure it's the real problem before buying a new one —no worries. I'll walk you through the step-by-step tests in this guide and show you exactly how to do it.
Where To Buy The CKP Sensor And Save
The following links will help you comparison shop for the crankshaft position sensor:
Crankshaft Position Sensor Connector Pinout
| 2001-2003 CKP Sensor Circuits | ||
|---|---|---|
| Terminal | Wire | Description |
| 1 | Brown with pink stripe (BRN/PNK) | 8 Volts DC |
| 2 | Dark blue with dark green stripe (DK BLU/DK GRN) | Ground |
| 3 | Brown with light blue stripe (BRN/LT BLU) | CKP Sensor Signal |
| 2004-2007 CKP 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 | Brown with light blue stripe (BRN/LT BLU) | CKP Sensor Signal |
TEST 1: Testing The CKP Signal With A Multimeter
We're gonna kick things off by checking if the crankshaft position sensor is putting out its ON/OFF voltage signal —and we'll do this by turning the engine by hand, no-starter motor involved.
Here's what that ON/OFF signal looks like:
- ON: Voltage spikes to 5 Volts.
- OFF: Drops down near 0 Volts.
This switching signal gets sent to the PCM through the brown with light blue stripe (BRN/LT BLU) wire —and that's the wire we'll be tapping into for this test.
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 turn the engine —if you do, it'll spin the engine way 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 rotate the engine by hand and see the ON/OFF voltage pulses clearly.
CAUTION: You may need to raise the front of your minivan to get your ratchet onto the crankshaft pulley bolt. If that's the case, make sure you support it with jack stands —never rely on the jack alone.
IMPORTANT: The CKP sensor has to stay plugged into the engine wiring harness during this test. Tap into the signal wire using a back-probe at the connector or a wire-piercing probe directly on the wire. You can see an example of that tool (and where to pick one up) here: Wire Piercing Probe.
Here's how to check the CKP signal step by step:
- 1
Disconnect the ignition coil pack.
NOTE: This is an important safety step to prevent the engine from accidentally starting. - 2
Set your multimeter to Volts DC mode.
- 3
Hook the black lead to the battery's negative (-) terminal.
- 4
Connect the red lead to the CKP signal wire (BRN/LT BLU), using either a back-probe at the connector or a wire-piercing probe on the wire itself.
NOTE: The CKP sensor must stay plugged in during this test. - 5
Turn the ignition key to the ON position (engine OFF).
- 6
Use your ratchet and socket to slowly turn the crankshaft pulley by hand.
NOTE: Don't use the starter —keep it manual.
IMPORTANT: Make sure to complete at least one full revolution of the crankshaft so the sensor passes by all the flywheel slots. - 7
You should see the voltage toggle between 5V and 0V.
When it drops to around 0.3–0.5V, that counts as 0 Volts.
NOTE: One full turn of the crankshaft should give you 12 ON (5V) pulses and 12 OFF (0V) dips —one for each flywheel slot the sensor reads.
Let's interpret your test result:
CASE 1: You see a clean ON/OFF switching signal. That's exactly what we want —it confirms the CKP sensor is working and sending a proper signal to the PCM.
This also tells us the sensor is getting its 8 Volt power supply and Ground from the PCM. No need for further CKP tests.
CASE 2: No signal switching seen. Double-check your connections and rerun the test.
If there's still no sign of an ON/OFF pulse on your multimeter, go to: TEST 2: Making Sure The CKP Sensor Is Getting 8 Volts.