How To Test The TPS (1993-1996 2.2L Buick Century, Oldsmobile Cutlass Ciera)

TEST 2: Making Sure The TPS Is Receiving 5 Volts

Like any other electrical component, the throttle position sensor needs power to function.

This power is in the form of 5 Volts DC and are supplied by your vehicle's fuel injection computer.

The wire that delivers these 5 Volts to the TPS is the gray (GRY) wire of the sensor's 3-wire connector.

In the photo above, I've labeled the GRY wire with the letter A.

These are the test steps:

1. 1

   Select Volts DC mode on your multimeter.

2. 2

   Disconnect the TP sensor from its connector.

3. 3

   Probe the grey (GRY) wire with the red multimeter test lead and an appropriate tool.
   
   The GRY wire is labeled with the letter A in the photo above.
   
   NOTE: Be careful not to damage the female terminal.

4. 4

   Connect the black multimeter test lead to the negative (-) battery terminal.

5. 5

   When everything is set up, have a helper rotate the key to its ON position but don't start the engine.

6. 6

   The multimeter should report 4.5 to 5 Volts DC.

Let's interpret your test results:

CASE 1: The GRY wire is delivering 4.5 to 5 Volts. This is the correct and expected test result and lets you know the TPS is getting power.

Your next and last step is to make sure the TPS is getting Ground. Go to: TEST 3: Making Sure The TPS Is Receiving Ground.

CASE 2: The GRY wire IS NOT delivering 4.5 to 5 Volts. Double check your connections and make sure you're testing the correct wire.

If the GRY wire is still not delivering 5 Volts DC, you can conclude that the TPS is not creating its signal due to a lack of power.

The most likely cause of this missing voltage is an open-circuit problem in the GRY wire. Your next step is to find out why this voltage is missing and restore it.

TEST 3: Making Sure The TPS Is Receiving Ground

So far, your test results have confirmed:

• The TPS voltage signal does not increase/decrease as you open/close the throttle plate (TEST 1).
• The GRY wire is delivering 5 Volts to the TP sensor (TEST 2).

In this last test section, you'll make sure that the black (BLK) wire of the sensor's 3-wire connector is delivering Ground.

You'll confirm the presence of Ground in the BLK wire with a simple multimeter voltage test.

Let's get started:

1. 1

   Select Volts DC mode on your multimeter.

2. 2

   Disconnect the TP sensor from its connector.

3. 3

   Probe the black (BLK) wire with the black multimeter test lead and an appropriate tool.
   
   The BLK wire is labeled with the letter B in the photo above.
   
   NOTE: Be careful not to damage the female terminal.

4. 4

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

5. 5

   When everything is set up, have a helper rotate the key to its ON position but don't start the engine.

6. 6

   The multimeter should display 10 to 12 Volts DC.

Let's interpret your test results:

CASE 1: Your multimeter registered 10 to 12 Volts. This is the correct and expected test result and confirms the TPS is getting Ground.

You can conclude that the TPS is bad and needs replacement if you have:

• Confirmed that the TP sensor is not producing a voltage signal that increases/decreases when you open/close the throttle plate (TEST 1).
• Confirmed that the TP sensor is receiving 4.5 to 5 Volts (TEST 2).
• Confirmed that the TP sensor is receiving Ground (this test section).

CASE 2: Your multimeter DID NOT register 10 to 12 Volts. Double check your connections and make sure you're testing the correct wire.

If the BLK wire is still not delivering Ground, you can conclude that the TPS is not creating its signal due to a lack of Ground.

The most likely cause of this missing Ground is an open-circuit problem in the BLK wire. Your next step is to find out why this Ground is missing and restore it.

More 2.2L Buick Century And Oldsmobile Cutlass Ciera Test Tutorials

If this tutorial was helpful, be sure and take a look at all of the 2.2L Buick Century and Oldsmobile Cutlass Ciera diagnostic tutorials in this index:

• GM 2.2L Index Of Articles.

Here's a sample of the tutorials you'll find there:

• How To Test The Fuel Pump (1993-1996 2.2L Buick Century, Oldsmobile Cutlass Ciera).
• How To Test The EGR Valve (1993-1995 2.2L Buick Century, Oldsmobile Cutlass Ciera).
• How To Test Engine Compression (1993-1996 2.2L Buick Century, Oldsmobile Cutlass Ciera).
• How To Test The MAP Sensor (1993-1996 2.2L Buick Century, Oldsmobile Cutlass Ciera).