How To Test The Camshaft Position Sensor (1996-1997 5.2L, 5.9L V8 Dodge Ram Van)

TEST 2: Making Sure The CMP Sensor Has 5 Volts

If you've made it this far, that means the CMP sensor didn't switch between 5 Volts and 0 Volts during TEST 1.

In some cases, the sensor isn't sending out its ON/OFF signal because it's not getting power from the fuel injection computer.

So in this part, we're gonna check if the violet with white stripe (VIO/WHT) with is delivering 5 Volts DC to the CMP sensor.

If the VIO/WHT wire is supplying 5 Volts, then the next step will be to make sure the sensor's also getting a solid Ground.

Here's what to do:

1. 1

   Unplug the CMP sensor from its connector.

2. 2

   Connect the black lead of your multimeter to the battery's negative (-) post.

3. 3

   Set your multimeter to measure DC Volts.

4. 4

   Turn the key to the ON position —but don't start or crank the engine.

5. 5

   Now, use the red lead to probe the front of the female terminal on the engine harness connector going to the VIO/WHT wire.
   
   NOTE: This step is done at the engine wiring harness connector —the one with the female terminals.

6. 6

   Your multimeter should show somewhere between 4.5 and 5 Volts.

Time to look at what your test result means:

CASE 1: The VIO/WHT wire is supplying 4.5 to 5 Volts. Perfect —that's what we want.

Your next move is to check for Ground at the black with light blue stripe wire. Head to: TEST 3: Making Sure The CMP Sensor Has Ground.

CASE 2: The VIO/WHT wire IS NOT supplying 4.5 to 5 Volts. Without those 5 Volts, the CMP sensor won't be able to send out its signal.

The usual suspect here is an open-circuit in the VIO/WHT wire —somewhere between the CMP sensor's connector and the fuel injection computer's connector.

Tracking down and fixing that power loss is your next step. It's outside the scope of this guide, but that missing voltage needs to be found and restored.

TEST 3: Making Sure The CMP Sensor Has Ground

Alright, the previous two tests have confirmed:

• The CMP signal doesn't switch between 0 and 5 Volts (TEST 1).
• The VIO/WHT wire is supplying 4.5 to 5 Volts (TEST 2).

So in this final section, we're gonna test the black with light blue stripe (BLK/LT BLU) wire to make sure it's delivering Ground to the CMP sensor.

IMPORTANT: The Ground for the CMP sensor comes from the fuel injection computer. Whatever you do, don't short the BLK/LT BLU wire to 12 Volts —you'll end up frying the computer. The multimeter method below is both safe and accurate.

Here's how to run the test:

1. 1

   Unplug the CMP sensor from its connector.

2. 2

   Hook up the red multimeter lead to the battery's positive (+) terminal.

3. 3

   Switch your multimeter to Volts DC mode.

4. 4

   Turn the ignition key to ON —don't start or crank the engine.

5. 5

   Touch the black multimeter lead to the female terminal connected to the BLK/LT BLU wire.
   
   NOTE: This step is done at the engine wiring harness connector —the one with the female terminals.

6. 6

   Your meter should show somewhere between 10 and 12 Volts if the Ground is there.

Here's what the results mean:

CASE 1: Ground is present at the BLK/LT BLU wire. That confirms the CMP sensor is getting the Ground it needs.

If there's still no signal coming from the sensor, it's time to replace it —but only if all these are true:

• The CMP signal doesn't switch between 0 and 5 Volts during TEST 1.
• 5 Volts are showing up on the VIO/WHT wire from TEST 2.
• Ground is confirmed on the BLK/LT BLU wire in this test.

CASE 2: Ground is missing at the BLK/LT BLU wire. Without that Ground, the CMP sensor can't generate a signal.

This usually points to a break somewhere in the BLK/LT BLU wire —between the sensor's connector and the fuel injection computer.

Chasing down the missing Ground is outside the scope of this guide, but the next step is to trace the wiring and fix the break.

More 5.2L, 5.9L V8 Dodge Ram Van Diagnostic Tutorials

I've written quite a few tutorials that may help you troubleshoot the issues on your V8 Dodge Ram van. You can find them in this index:

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

Here's a small sample of the articles/tutorials you'll find in the index:

• How To Test The Intake Air Temp (IAT) Sensor (1992-1997 5.2L, 5.9L V8 Dodge Ram Van).
• Testing The Front Oxygen Sensors (1996-2003 5.2L, 5.9L V8 Dodge Ram Van).
• How To Test The TPS (1992-1997 5.2L, 5.9L V8 Dodge Ram Van).
• How To Test For A Blown Head Gasket (1989-2003 5.2L, 5.9L V8 Dodge Ram Van).