Testing the crankshaft position (CKP) sensor on your 3.0L V6 Chrysler, Dodge, or Plymouth minivan is something that you can do with a simple multimeter. Not only that, this multimeter test is a very accurate test that'll tell you if the crankshaft position sensor is bad or not.
In this tutorial, I'll explain the 3 different tests in a step-by-step manner so that you can find out if the crankshaft sensor is behind your mini-vans no start problem
Contents of this tutorial at a quick glance:
- Symptoms Of A Bad Crankshaft Position Sensor.
- Circuit Descriptions Of The Crankshaft Position Sensor.
- TEST 1: Testing The Crankshaft Position Signal.
- TEST 2: Making Sure The Crank Sensor Has Power And Ground.
- Where To Buy The Crankshaft Position Sensor.
Symptoms Of A Bad Crankshaft Position Sensor
The crankshaft position sensor is located on the transmission bell housing and when it fails, your mini-van will crank but not start.
Unfortunately, the crankshaft position sensor can fail intermittently. In these cases, it works most of the time but will fail every now and then and cause the engine to not start.
The focus of this tutorial is diagnosing and testing a CKP sensor that has failed completely.
Circuit Descriptions Of The Crankshaft Position Sensor
The crank sensor is 3-wire Hall Effect sensor. Below is a brief description of the three wires that connect to the crankshaft position sensor.
|Crankshaft Position Sensor Connector|
|1||Orange||Power (5 or 8 Volts DC)|
|2||Black with light blue stripe||Sensor ground|
|3||Gray with black stripe||Crank Position Signal|
TEST 1: Testing The Crankshaft Position Signal
The very first thing that we're going to do is to connect our multimeter to the crankshaft position sensor signal wire. Then we're going to manually crank the engine using 1/2" ratchet and appropriate socket on the crankshaft pulley.
As the engine turns, we'll see if the sensor is creating an ON/OFF signal. ON is when it outputs 5 Volts DC and OFF is when it outputs 0 Volts DC.
If the crankshaft position sensor is bad, then your multimeter will stay stuck reading a single voltage of value as you turn the engine.
IMPORTANT: The crankshaft position sensor must be connected to its engine harness connector for this test to work. You'll need to connect your multimeter test lead to a back probe or a wire piercing probe to read the crank signal. You can see an example of a wire piercing probe here: Wire Piercing Probe Review (Power Probe PWPPPPP01) (at: easyautodiagnostics.com).
These are the test steps:
Place your multimeter in Volts DC mode and re-connect the distributor to its electrical connector.
Disconnect the ignition coil from its electrical connector. This is an important safety precaution!
With the red multimeter lead, probe the GRY/BLK wire of the crank sensor connector.
The gray with black stripe (GRY/BLK) wire connects to the female terminal labeled with the number 3 in the illustration above.
Connect the black multimeter lead directly on the battery negative (-) terminal.
Turn the ignition key to the ON position and turn the engine by hand using the 1/2" ratchet wrench and appropriate socket on the crankshaft pulley. For the accuracy of the test, do not use the starter motor.
Your multimeter will read an ON/OFF voltage of 5 Volts and 0 Volts (if the crankshaft position sensor is functioning correctly).
ON is when the multimeter reads 5 Volts DC and OFF is when it reads 0 Volts DC.
Let's take a look at what your test results mean:
CASE 1: The multimeter read the indicated ON/OFF DC voltage. This is the correct and expected test result and tells you that the crankshaft position sensor is functioning correctly.
The 'cranks but does not start' condition on your 3.0L V6 mini-van is not due to a defective crankshaft position sensor.
CASE 2: The multimeter DID NOT read the indicated ON/OFF DC voltage. This test result tells you that the crank sensor is defective. Before you replace it, make sure it's getting power and ground. For this test go to: TEST 2: Making Sure The Crank Sensor Has Power And Ground.