Bench-Testing The CMP Sensor (1999-2006 V8 Silverado, Sierra, Suburban, Tahoe, Yukon)

I have found that one of the less complicated ways to test the camshaft position (CMP) sensor, on the 1999-2006 V8 Silverado (Sierra, Suburban, Tahoe, or Yukon), is to remove it and bench-test it.

So, in this tutorial I'm gonna' explain how to bench-test it with a 9 Volt battery and find out if it's really bad or (not).

You can find this tutorial in Spanish here: Cómo Probar El Sensor CMP En Banco (1999-2006 V8 Silverado, Sierra, Suburban, Tahoe, Yukon) (at: autotecnico-online.com).

APPLIES TO: This tutorial applies to the following vehicles:

Chevrolet:

• Silverado (1500, 2500):
  • 4.8L, 5.3L: 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
• Silverado (2500):
  • 6.0L: 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
• Suburban (1500):
  • 5.3L: 2000, 2001, 2002, 2003, 2004, 2005, 2006
• Suburban (2500):
  • 6.0L: 2000, 2001, 2002, 2003, 2004, 2005, 2006
• Tahoe:
  • 4.8L, 5.3L: 2000, 2001, 2002, 2003, 2004, 2005, 2006

GMC:

• Sierra (1500, 2500):
  • 4.8L, 5.3L: 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
• Sierra (2500):
  • 6.0L: 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
• Yukon:
  • 4.8L, 5.3L: 2000, 2001, 2002, 2003, 2004, 2005, 2006
• Yukon XL (1500):
  • 5.3L: 2000, 2001, 2002, 2003, 2004, 2005, 2006
• Yukon XL (2500):
  • 6.0L: 2000, 2001, 2002, 2003, 2004, 2005, 2006

RELATED WIRING DIAGRAMS:

• CMP And CKP Sensor Circuit Diagram (1999-2006 V8 Silverado, Sierra, Suburban, Tahoe, Yukon).
• Ignition Coil Circuit Wiring Diagram (1999-2002 V8 Chevrolet Silverado, GMC Sierra).

RELATED CMP SENSOR TROUBLE CODES:

• P0341 -What Does It Mean? (1999-2006 V8 Silverado, Sierra, Suburban, Tahoe, Yukon).
• P0342 -What Does It Mean? (1999-2006 V8 Silverado, Sierra, Suburban, Tahoe, Yukon).
• P0343 -What Does It Mean? (1999-2006 V8 Silverado, Sierra, Suburban, Tahoe, Yukon).

What Tools Do I Need To Bench Test The CMP Sensor?

The cool thing about bench testing the CMP sensor is that you don't need expensive tools to do it.

Here's what you'll need:

• An LED light.
  • Don't have one, you can buy it here: The LED Light Test Tool And How To Make One.
• Jumper wires with insulated alligator clips.
  • You can buy them here: 10 Pieces and 5 Colors Test Lead Set & Alligator Clips (at: amazon.com).
• Telescoping magnet pick up tool.
  • You can buy one here: SE 30" Telescoping Magnetic Pick-Up Tool (at: amazon.com).

As you can see, nothing that's gonna' break the bank.

Where To Buy The Camshaft Position Sensor And Save

The following links will help you to comparison shop the original AC Delco and the Dorman camshaft position sensor on your Silverado (Sierra, Suburban, Tahoe, or Yukon):

Not sure if the above camshaft position sensor fits your particular GM vehicle? Don't worry, once you click on the links and arrive on the site, they'll make sure it fits! If it doesn't, they'll find you the right one.

CMP Sensor Circuit Descriptions

The following table gives a brief description of what each of the 3 male terminals of the CMP sensor do:

Terminal	Wire	Description
A	Brown With White Stripe (BRN/WHT)	CMP Signal
B	Pink With Black Stripe (PNK/BLK)	Ground
C	Red (RED)	12 Volts

TEST 1: Connecting The Jumper Wires To The CMP Sensor

The male terminals of the CMP sensor are spaced closely together, and this presents a challenge when connecting the jumper wires with insulated alligator clips.

Why? For 2 reasons:

• 3 insulated alligator clips will not fit in the small space of the CMP sensor's connector.
• Non-insulated alligator clips will come in contact with each other (while connected to the sensor's male terminals).

But there's a way around this! What I've always done, is to:

• Use an insulated jumper wire on male terminals C and A only.
• Use a non-insulated jumper wire on male terminal B.
• Use 2 thin pieces of cardboard (or 2 pieces of an index card) to separate the alligator clips.

I've used this method countless times and it works flawlessly and it's how I'm gonna' show you how to bench test the CMP sensor.

You can find the size dimensions of the cardboard seperator here: Cardboard Separator Dimensions.

OK, let's get started:

PART 1: Terminal C

1. 1

   Connect an insulated alligator clip to male terminal C. See photo 1 of 6.
   
   IMPORTANT: Make sure that the rubber insulator is covering the clip and the male terminal.

2. 2

   Connect the other end of the insulated jumper wire to the positive (+) terminal of the 9 Volt battery.

PART 2: Terminal B

1. 3

   Place a thin piece of cardboard (or index card) between the insulated alligator clip and male terminal B. See photo 2 of 6.

2. 4

   Connect a non-insulated alligator clip to male terminal B. See photo 3 of 6.

3. 5

   Connect the other end of the jumper wire to the negative (-) terminal of the 9 Volt battery.

PART 3: Terminal A

1. 6

   Place a thin piece of cardboard (or index card) between the non-insulated alligator clip and male terminal A. See photo 4 of 6.

2. 7

   Connect an insulated alligator clip to male terminal A. See photo 5 of 6.

3. 8

   Connect the other end of the jumper wire to the red wire (lead) of the LED light.
   
   IMPORTANT: The other end of the jumper wire (that connects to terminal A) must be connected to the red lead of the LED light for this test to function.

PART 4: Black Lead Of LED Light

1. 9

   Connect the black lead of the LED light to the negative (-) terminal of the 9 Volt battery. See photo 6 of 6.

2. 10

   Your jumper wire connections should resemble my setup on photo 6 of 6.

Alright, let's see what we've got:

CASE 1: Your jumper wire connections resemble the connections in photo 6 of 6. Awesome!

The next step is to use a magnet to verify that the CMP sensor is creating a CMP signal. Go to: TEST 2: Using A Magnet To Induce The CMP Signal.

CASE 2: Your jumper wire connections DO NOT resemble the connections in photo 6 of 6. Recheck all of your connections.

Once your jumper wire connections are in their correct places, go to: TEST 2: Using A Magnet To Induce The CMP Signal.