The distributor pickup coil (also known as the camshaft position sensor) can easily be tested with a multimeter on the 1993-1997 5.2L V8 Jeep Cherokee.
In 3 tests you can easily find out if it's bad (or not) and in this tutorial I'll explain how to do them.
I'll also show you where you can buy it and save a bucks on its purchase.
NOTE: The camshaft position sensor is also known as the distributor pickup coil.
Contents of this tutorial:
- Symptoms Of A Bad Camshaft Position (CMP) Sensor.
- Circuit Descriptions Of The Camshaft Position Sensor.
- TEST 1: Testing The Camshaft Position Signal.
- TEST 2: Making Sure The CMP Sensor Has Power.
- TEST 3: Making Sure The CMP Sensor Has Ground.
- Where To Buy The Camshaft Position Sensor.
- More 5.2L Jeep Grand Cherokee Tutorials.
APPLIES TO: This tutorial applies to the following vehicles since they use the exact same camshaft position (CMP) sensor:
- 5.2L V8 Jeep Cherokee: 1993, 1994, 1995, 1995, 1996, 1997.
IGNITION COIL TEST: The following tutorial will help you test the ignition coil: How To Test The Ignition System (1993-1998 5.2L Grand Cherokee).
WIRING DIAGRAM: You can find the ignition system wiring diagrams here:
- Ignition System Wiring Diagram (1993-1995 5.2L Jeep Grand Cherokee).
- Ignition System Wiring Diagram (1996-1998 5.2L Jeep Grand Cherokee).
Symptoms Of A Bad Camshaft Position (CMP) Sensor
The fuel injection computer uses the camshaft position sensor and the crankshaft position sensor to start activating the ignition coil and the fuel injectors.
A camshaft position sensor failure usually causes the engine to not start due to a lack of spark and fuel injection.
On the 1996-1997 5.2L Jeep Grand Cherokee, which is OBD II equipped, you may see the following trouble code stored in the computer's memory:
- P0340: No Camshaft Signal At PCM.
On the 1993-1995 OBD I equipped 5.2L Jeep Grand Cherokee, you may see the following trouble code stored in the computer's memory:
- Code 54: No Cam Sync Signal Detected.
Circuit Descriptions Of The Camshaft Position Sensor
The camshaft position sensor needs power and Ground to activate and produce its signal. As such, it has 3 wires coming out of its electrical connector.
In the table below you'll find a short description of each of the 3 wires:
| 1993-1995 Camshaft Position Sensor Connector | ||
|---|---|---|
| Pin | Wire Color | Description |
| 1 | White with black stripe (WHT/BLK) | Power (8 Volts DC) |
| 2 | Black with light blue stripe (BLK/LT BLU) | Sensor Ground |
| 3 | Gray with black stripe (GRY/BLK) | CMP Signal |
| 1996-1997 Camshaft Position Sensor Connector | ||
|---|---|---|
| Pin | Wire Color | Description |
| 1 | White with black stripe (WHT/BLK) | Power (5 Volts DC) |
| 2 | Black with light blue stripe (BLK/LT BLU) | Sensor Ground |
| 3 | Gray with black stripe (GRY/BLK) | CMP Signal |
The following ignition system wiring diagrams will further help you identify the camshaft position sensor circuits:
- Ignition System Wiring Diagram (1993-1995 5.2L Jeep Grand Cherokee).
- Ignition System Wiring Diagram (1996-1998 5.2L Jeep Grand Cherokee).
The camshaft position sensor creates an ON/OFF voltage signal as the engine turns. ON is when the CMP signal is at 5 Volts DC. OFF is when the CMP signal is at 0 Volts.
The cool thing is that we can see this ON/OFF voltage with a multimeter, and this is how we're gonna' test it.
TEST 1: Testing The Camshaft Position Signal
The first thing that we're gonna' do is to see if the camshaft position (CMP) sensor is producing an ON/OFF voltage signal. As mentioned before, ON is when the CMP signal is 5 Volts DC and OFF is when it's 0 Volts.
The wire that carries the camshaft position signal, to your 5.2L V8 Jeep Cherokee's fuel injection computer, is the gray with black stripe (GRY/BLK) wire.
The GRY/BLK wire is the wire labeled with the number 3 in the photo above.
The CMP sensor's connector and the CKP sensor's connector are located near each other. To find the correct connector keep in mind that the camshaft position (CMP) sensor is located in the distributor and the crankshaft position (CKP) sensor is bolted onto the transmission bell housing.
IMPORTANT: The camshaft position sensor must be connected to its engine harness connector for this test to work. You'll need to use a back probe or a wire piercing probe to read the CMP voltage signal within the wire. You can see an example of a wire piercing probe here: Wire Piercing Probe Review (Power Probe PWPPPPP01).
NOTE: Don't have a multimeter or need to upgrade yours? Check out my recommendation: Buying A Digital Multimeter For Automotive Diagnostic Testing (at: easyautodiagnostics.com).
These are the test steps:
- 1
Place your multimeter in Volts DC mode.
- 2
Disconnect the ignition coil from its electrical connector. This is an important safety precaution!
NOTE: Don't remove the distributor cap from the distributor. The distributor cap must be in place to hold down the camshaft position sensor. - 3
With the red multimeter test lead, probe the gray with black stripe (GRY/BLK) wire of the cam sensor connector.
NOTE: The camshaft position sensor must remain connected to its engine wiring harness connector to be able to read its signal. - 4
Connect the black multimeter test lead directly on the battery negative (-) terminal.
- 5
Have your helper crank the engine for a few seconds once the multimeter test lead connections are set up.
- 6
Your multimeter should see the voltage switch between 5 Volts and 0 Volts DC as the engine is cranking.
Let's examine your CMP signal test result:
CASE 1: The multimeter read the indicated ON/OFF DC voltage. This is the correct and expected test result and tells you that the camshaft position sensor is functioning correctly.
Since the camshaft position sensor IS NOT defective, something else is causing your 5.2L V8 Jeep Grand Cherokee to not start.
CASE 2: The multimeter DID NOT read the indicated ON/OFF DC voltage. This test result usually means that the camshaft position sensor is defective.
Before you replace it, make sure it's getting power and Ground. For the next test go to: TEST 2: Making Sure The CMP Sensor Has Power.
