APP Sensor Tests (2004-2006 2.8L Chevrolet Colorado, GMC Canyon)

TEST 2: APP Sensor 1 Resistance Tests (2 Of 2)

APP Sensor 1 Resistance Tests (2 Of 2). How To Test The APP Sensor Assembly (2004, 2005, 2006 2.8L Chevrolet Colorado, GMC Canyon)

In this test section, you'll test the resistance across terminals 2 and 4 while depressing and then releasing the accelerator pedal.

If all is OK, you should see:

  • The resistance decreases as you depress the accelerator pedal.
  • The resistance increases as you release the accelerator pedal.

NOTE: The easiest way to connect your multimeter's test leads to the male terminals of APP sensor 1 is with jumper wires with alligator clips on both ends.

These are the test steps:

  1. 1

    Disconnect the APP sensor assembly from its electrical connector.

  2. 2

    Place your multimeter in Ohms mode.

  3. 3

    Connect one multimeter test lead to terminal 2.

  4. 4

    Connect the other multimeter test lead to terminal 4.

  5. 5

    Note the Ohms reading on your multimeter.

    At this point you'll see a resistance reading somewhere around 2k to 3K Ohms.

    If you don't, don't worry. Continue on to the next step.

  6. 6

    Slowly depress the pedal by hand till it bottoms out.

  7. 7

    The resistance value should decrease as you depress the pedal.

  8. 8

    Slowly release the accelerator pedal.

  9. 9

    The resistance value should increase back to the original value you saw in step 5.

Let's examine your test results:

CASE 1: The resistance increased/decreased without any gaps. This is the correct test result.

The next step is to test APP sensor 2. Go to: TEST 3: APP Sensor 2 Resistance Tests (1 Of 2).

CASE 2: The resistance DID NOT decrease. This lets you know that APP sensor 1 is bad.

Replace the accelerator pedal assembly.

CASE 3: The resistance DID NOT increase. This lets you know that APP sensor 1 is bad.

Replace the accelerator pedal assembly.

CASE 4: The resistance DID NOT decrease/increase. This lets you know that APP sensor 1 is bad.

Replace the accelerator pedal assembly.

TEST 3: APP Sensor 2 Resistance Tests (1 Of 2)

APP Sensor 2 Resistance Tests (1 Of 2). How To Test The APP Sensor Assembly (2004, 2005, 2006 2.8L Chevrolet Colorado, GMC Canyon)

Now that you've tested and confirmed that APP sensor 1 is OK, it's time to perform the first of the two APP sensor 2 tests.

Specifically, you'll test across terminals 1 and 5 for an open-circuit or a short-circuit problem. If you find no problems, your next step will be TEST 4.

Let's get started:

  1. 1

    Disconnect the APP sensor assembly from its electrical connector.

  2. 2

    Place your multimeter in Ohms mode.

  3. 3

    Connect one multimeter test lead to terminal 1.

  4. 4

    Connect the other test lead to terminal 5.

  5. 5

    Your multimeter should read continuity.

    You'll usually see an Ohms reading somewhere between 2K to 3K Ohms.

Let's examine your test results:

CASE 1: The multimeter registered continuity between terminals 1 and 5. This is the correct test result.

Your next step is to test the resistance of APP sensor 2 while depressing/releasing the accelerator pedal. For this test go to: TEST 4: APP Sensor 2 Resistance Tests (2 Of 2).

CASE 2: The multimeter registered 0 Ohms (or a value very close to it). This test result confirms a short-circuit problem between terminals 1 and 5.

With this test result, you can conclude that the accelerator pedal assembly is defective and needs replacement.

CASE 3: The multimeter reports no continuity (the letters OL are displayed). This test result confirms an open-circuit problem between terminals 1 and 5.

With this test result, you can conclude that the accelerator pedal assembly is defective and needs replacement.

Chevrolet Vehicles:

  • Colorado 2.8L
    • 2004, 2005, 2006

GMC Vehicles:

  • Canyon 2.8L
    • 2004, 2005, 2006