How To Test The Throttle Position Sensor (1992-1996 2.2L Toyota Camry)

The throttle position sensor, on the 2.2L Toyota Camry, is two sensors in one assembly. One part of the TPS assembly is an idle switch and the other is the actual throttle position sensor.

In this tutorial, I'll show you how to test the TPS part of the assembly in a step-by-step way.

ES You can find this tutorial in Spanish here: Cómo Probar El Sensor TPS (1992-1996 2.2L Toyota Camry) (at: autotecnico-online.com).

APPLIES TO: This tutorial applies to the following vehicles:

• 2.2L Toyota Camry: 1992, 1993, 1994, 1995, 1996.

NOTE: If you need to test the idle switch portion of the TPS or if you need to adjust the TPS, take a look at this tutorial:

• TPS Idle Switch Multimeter Test (1992-1996 2.2L Toyota Camry).

Symptoms Of A Bad Throttle Position Sensor

The throttle plate opens and closes, to let more or less air into the engine, when you step on or off the accelerator pedal. It's the TP sensor's job to measure how much it opens and report this throttle angle to your Toyota Camry's fuel injection computer.

Since the TPS is such a critical role in your 2.2L Camry's engine management system, when it fails, you'll see or more of the following symptoms:

• If your 2.2L Toyota is OBD II equipped (1996+), you'll see one of the following trouble codes:
  • P0120: Throttle Position Sensor Circuit.
  • P0121: Throttle Position Sensor Circuit.
• If your 2.2L Toyota is OBD I equipped, you'll see one of the following trouble codes:
  • 41: Throttle Position Sensor Signal.
• Hesitation when accelerating the engine.
• Lack of power.
• Bad gas mileage.

Circuit Descriptions Of The TPS

The table below has a brief description of the 4 wires that make up the TPS connector.

TPS Circuits (1992-1996 2.2L Toyota Camry)
Terminal	Wire	Description
1	BRN	Sensor Ground
2	BLU	Idle Switch Signal
3	BLK	TPS Signal
4	RED	5 Volts

NOTE: The above circuit descriptions apply only to the 1992-1996 2.2L Toyota Camry throttle position sensor.

Where To Buy The TPS And Save

Probably, the best place to save on the purchase of a new TPS, for your 2.2L Toyota Camry, is online. Check out the following links. I think they'll save you a few bucks:

Not sure if the above TPS fits your particular 2.2L Toyota Camry? Don't worry, once you get to the site they'll make sure it fits by asking you the specifics of your particular Toyota vehicle. If it doesn't fit, they'll find you the right one.

TEST 1: Testing The TPS Voltage Signal

The very first thing that we'll do, to find out if the TPS has failed or not on your Camry, is to check the throttle angle voltage signal with a multimeter connected to the sensor's black (BLK) wire.

If the TPS is good, then the voltage signal that your multimeter reports should increase as you manually open the throttle plate. This voltage signal should then decrease as you close the throttle plate.

If the TPS is bad, your multimeter will report a single value that won't increase/decrease as you open/close the throttle plate.

IMPORTANT: You don't need to remove the TPS to bench test it, since the instructions below are for an on-car test. Since the TPS needs to remain connected to its connector, you'll need to use a back-probe or a wire-piercing probe to measure the TP signal voltage.

NOTE: Don't have a multimeter or you need to upgrade yours, this is the one that I use and recommend: Tekpower TP8268 AC/DC Auto/Manual Range Digital Multimeter (Amazon affiliate link).

Here are the steps:

1. 1

   Place your multimeter in Volts DC mode.

2. 2

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

3. 3

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

4. 4

   Probe the BLK wire of the TPS connector with the red multimeter test lead.
   
   The BLK wire is labeled with the number 3 in the photo above.

5. 5

   Your multimeter should report a voltage between 0.2 to 0.9 Volts DC with the throttle plate closed.
   
   If your multimeter doesn't, don't worry about it just yet, continue with the other steps.

6. 6

   Slowly open the throttle (by hand and from the engine compartment).
   
   The voltage numbers should increase as the throttle plate opens.
   
   This increase in voltage should be smooth and without any gaps or skips. Once the throttle is wide open, your multimeter should read somewhere between 3.5 to 4.5 Volts DC.

7. 7

   Slowly close the throttle.
   
   As the throttle is closing, you should see the voltage decrease smoothly and without any gaps or skips, to the exact same voltage you noticed in step 5.

8. 8

   Lightly tap on the throttle position sensor with the handle of a screw-driver (or something similar, and I want to emphasize the words ‘lightly tap’) as you slowly open and close the throttle and observe the multimeter.
   
   If the TPS is bad, the tapping will cause the voltage numbers to skip or go blank. If the TPS is OK, the tapping will have no effect on the voltage numbers.

9. 9

   Repeat step 8 several times to make sure of your multimeter test results.

Let's take a look at your test results:

CASE 1: The throttle angle voltage increased and decreased as you opened and closed the throttle plate. This test result confirms that the TP sensor is OK and not defective.

CASE 2: The throttle angle voltage DID NOT increase (and/or decrease) as you opened and closed the throttle plate. This test result confirms the throttle position sensor trouble code lighting up the check engine light on your 2.2L Toyota Camry.

If I where in your shoes and to be sure that the TPS has truly failed, I would still make sure that the TP sensor is getting both power and Ground. To check for power, go to: TEST 2: Making Sure The TPS Is Getting 5 Volts.

CASE 3: The multimeter DID NOT register any voltage. This test result doesn't condemn the TP sensor as bad just yet.

Why? Because the TP sensor may be missing either power or Ground. So the next step is to check that the TP sensor is getting power, go to: TEST 2: Making Sure The TPS Is Getting 5 Volts.

TEST 2: Making Sure The TPS Is Getting 5 Volts

If in TEST 1, your 2.2L Toyota Camry did not pass the test, you need to make sure it's getting both power and Ground (before condemning it as bad).

In this test section, we're gonna make sure the red (RED) wire, of the TP sensor's connector is supplying 5 Volts.

Once we've confirmed that the TP sensor is getting power, we'll move on to TEST 3 and make sure the sensor is getting Ground.

Let's begin:

1. 1

   Place your multimeter in Volts DC mode.

2. 2

   Disconnect the TPS from its connector.

3. 3

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

4. 4

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

5. 5

   Probe the female terminal that corresponds to the red wire of the TPS connector.

6. 6

   Your multimeter should read 4.5 to 5 Volts DC.

Let's interpret your test results:

CASE 1: 4.5 to 5 Volts are present. This is the correct and expected test result.

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

CASE 2: 4.5 to 5 Volts are not present. Take a look at your test connections and make sure that you're testing the correct terminal.

If power is not present, then you can conclude that there's an open-circuit problem in the wire between the TP sensor harness connector and the PCM's harness connector. In the extreme of cases, the PCM has an internal problem (although this is very rare).

Although testing this issue is beyond the scope of this tutorial, you have now eliminated the throttle position sensor (TPS) on your 2.2L Toyota Camry as being the cause of the problem and/or the TP sensor diagnostic trouble code (DTC) lighting up the check engine light (CEL).

TEST 3: Making Sure The TPS Is Getting Ground

So far, you have confirmed:

• The TPS is not creating a voltage signal that increases/decreases (TEST 1).
• The TPS is getting 4.5 to 5 Volts DC (TEST 2.)

In this last test section, we're gonna make sure the brown (BRN) wire, of the TP sensor's connector is supplying Ground.

IMPORTANT: The PCM is the one that feeds this Ground to the throttle position sensor (TPS). Be careful and don't short/connect this wire to battery voltage or you'll fry the PCM.

This is what you need to do:

1. 1

   Place your multimeter in Volts DC mode.

2. 2

   Disconnect the TPS from its connector.

3. 3

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

4. 4

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

5. 5

   Probe the female terminal that corresponds to the brown wire of the TPS connector.

6. 6

   Your multimeter should read 10 to 12 Volts DC if Ground is present in the BRN wire.

Let's take a look at what your test results mean:

CASE 1: Ground is present. This is the correct and expected test result.

You can conclude that the TPS is bad only if all tests have confirmed that:

1. The TP sensor IS NOT producing a varying voltage signal when manually opening/closing the throttle plate (TEST 1).
2. The TP sensor is receiving 4.5 to 5 Volts DC (TEST 2).
3. The TP sensor is getting Ground (this test section).

You'll need to adjust the TPS assembly if you replace it. The following heading will help you with this procedure: Adjusting The Throttle Position Sensor Assembly (this heading is found in the tutorial: TPS Idle Switch Multimeter Test (1992-1996 2.2L Toyota Camry)).

CASE 2: Ground is not present. Take a look at your test connections and make sure that you're testing the correct terminal.

If Ground is still missing, then you can conclude that there's an open-circuit in the wire between the TP sensor harness connector and the PCM's harness connector. In the extreme of cases, the PCM has an internal problem (although this is very rare).

Although testing this issue is beyond the scope of this tutorial, you have now eliminated the throttle position sensor (TPS) on your 2.2L Toyota Camry as being the cause of the problem and/or the TP sensor diagnostic trouble code (DTC) lighting up the check engine light (CEL).

More 2.2L Toyota Camry Tutorials

You can find a complete list of 2.2L Toyota Camry tutorials and wiring diagrams in this index:

• 2.2L Toyota Camry And Celica Index of Articles.

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

• How To Test Engine Compression (1990-2001 2.2L Toyota Camry, Celica).
• How To Test The TPS With A Multimeter (1997-2001 2.2L Toyota Camry).
• How To Test For A Blown Head Gasket (1990-2001 2.2L Toyota Camry, Celica).
• How To Test The MAP Sensor (1997-2001 2.2L Toyota Camry).