How To Test The Crankshaft Position Sensor (1992-1997 5.2L, 5.9L V8 Dodge Ram Pickup)

TEST 2: Making Sure The CKP Sensor Has Power

Just like any other electrical part on your Dodge Ram pickup, the crankshaft position (CKP) sensor needs both power and Ground to do its job.

In this part of your CKP sensor diagnostic, you'll use your multimeter to make sure it's actually getting power.

To get specific, depending on the year of particular V8 Dodge Ram pickup, the power comes in the form of 8 or 5 Volts DC. This power is sent by the PCM when the key is in the ON position (and, of course, when the engine's cranking or running too).

On the 1992-1995 pickups, the orange (ORG) wire is the power (8 Volt) supply wire.

On the 1996-1997 pickups, the purple with white stripe (PPL/WHT) is the power wire, delivering 5 Volts.

Here's what you need to do:

1. 1

   Unplug the CKP sensor from the engine wiring harness connector.

2. 2

   Attach the black multimeter lead to the battery's negative (-) terminal.

3. 3

   Switch your multimeter to Volts DC mode.

4. 4

   Use the red multimeter lead to probe female terminal 1 of the CKP sensor connector.
   
   Confirm that the terminal actually corresponds to the ORG or VIO/WHT wire.
   
   NOTE: This test is done on the engine wiring harness connector, which has female terminals.

5. 5

   Turn the ignition key to the ON position —no need to crank the engine at all.

6. 6

   You should see between 4.5 and 5 Volts DC on your multimeter if everything's working right and the PCM is sending power down the line.

Alright, here's how to read your results:

CASE 1: You have 4.5 to 5 Volts DC. That confirms the CKP sensor is getting power from the PCM like it should.

But there's still one more thing to check before blaming the CKP sensor —you'll need to test the Ground circuit next. Head over to: TEST 3: Making Sure The CKP Sensor Has Ground.

CASE 2: You don't have 4.5 to 5 Volts DC. Double-check your test setup and run the test again.

If you still don't see 5 Volts, you've confirmed the problem: the CKP sensor isn't working because it's not getting power. Replacing the sensor won't fix it.

Tracking down why those 5 Volts are missing goes beyond the scope of this tutorial, but solving that issue will get your V8 Dodge Ram back to starting again.

TEST 3: Making Sure The CKP Sensor Has Ground

Up to this point, all of your diagnostic testing on the CKP sensor has confirmed the following:

• TEST 1: The CKP sensor isn't producing an ON/OFF voltage signal.
• TEST 2: The power supply wire at the harness connector is supplying 8 or 5 Volts DC to the CKP sensor.

In this final test section, you're gonna check if the sensor's getting Ground —and you'll do it with a simple voltage check using your multimeter.

The CKP sensor gets its Ground through the black with light blue stripe (BLK/LT BLU) wire coming from the fuel injection computer (PCM).

IMPORTANT: Be extra careful here. The BLK/LT BLU wire connects directly to the PCM —don't let this wire touch battery voltage or you'll fry it (the PCM). The test below is a completely safe way to check the BLK/LT BLU wire for Ground.

Here's what to do:

1. 1

   Unplug the CKP sensor from its harness connector.

2. 2

   Connect the red lead of your multimeter to the positive (+) battery terminal.

3. 3

   Set the multimeter to Volts DC mode.

4. 4

   Touch the black multimeter lead to the female terminal marked number 2 of the CKP sensor connector.
   
   Make sure the terminal connects to the BLK/LT BLU wire.

5. 5

   Turn the key to the ON position. No need to crank the engine.

6. 6

   You should see a reading between 10 and 12 Volts DC on your multimeter if the PCM is sending Ground like it should.

Now, let's break down your test results:

CASE 1: You got a reading of 10 to 12 Volts DC. That tells you the BLK/LT BLU wire is delivering Ground to the CKP sensor like it's supposed to.

At this point, if you've confirmed all three tests:

• TEST 1: The CKP sensor isn't sending an ON/OFF 5-Volt signal.
• TEST 2: It's getting power (5 or 8 Volts) just fine.
• This test: It's also getting a good Ground.

Then the CKP sensor is definitely bad and needs to be replaced.

CASE 2: You did NOT get a reading of 10 to 12 Volts DC. Double-check your setup and test again to be sure.

If there's still no 12 Volts, it means the BLK/LT BLU wire isn't providing Ground. In this case, the CKP sensor isn't the root cause of your no-start problem —the missing Ground is. Fixing that missing Ground will be your next step to get the engine running again.

More 5.2L, 5.9L V8 Dodge Ram Pickup Tutorials

You can find a complete list of wiring diagrams and diagnostic tutorials for the V8 Dodge Ram pickup here:

• 5.2L, 5.9L V8 Dodge Ram Index Of Articles.

Here's a sample of the tutorials you'll find in the old index:

• How To Test The Intake Air Temp (IAT) Sensor (1992-1997 5.2L, 5.9L V8 Dodge Ram Pickup).
• How To Test The MAP Sensor (1992-1996 5.2L, 5.9L V8 Dodge Ram Pickup).
• How To Test The Fuel Pump (1992-2003 5.2L, 5.9L V8 Dodge Ram Pickup).
• Testing The Oxygen Sensors (1996-2003 5.2L, 5.9L V8 Dodge Ram Pickup).