Finding Faulty Silverado Tps Monitors: A Step-By-Step Guide

The Chevy Silverado is a popular pickup truck known for its impressive towing capacity, toughness, and technology. One of the many features of this truck is the TPMS (Tire Pressure Monitoring System), which monitors the tire pressure and temperature, alerting drivers to any issues before they become serious. However, a faulty tire pressure sensor can cause the TPMS to malfunction, resulting in a Service Tire Pressure Monitoring System warning. This article will discuss the common causes of this issue and guide you through the process of identifying and resolving the problem.

Check for inconsistent power

To check for inconsistent power in your Chevy Silverado, you can perform the following steps:

Step 1: Check for Error Codes

Locate any error codes that may be triggering the inconsistent power issue. This can be done by connecting a good scanner that can read engine, transmission, body, and chassis systems. Check for error codes related to the throttle position sensor (TPS), such as P0122 or P0124, which indicate issues with the TPS sensor circuit.

Step 2: Inspect the Throttle Position Sensor (TPS)

The TPS is responsible for measuring how much you push down on the gas pedal and relaying that information to the throttle valve, which adjusts the acceleration accordingly. Inspect the TPS for any signs of damage or wear. The TPS is mounted on the throttle body, which is located on the driver's side of the engine.

Step 3: Test the TPS with a Multimeter

Turn the ignition to the "ON" position to power up the sensors. Locate the TPS sensor and disconnect it by lifting the harness locking tab. Identify the wire leading to PIN C, which should be gray or gray with a red stripe. Test this wire with a voltmeter and ensure you read 5 volts. Next, check the wire leading to PIN B, which is the low reference signal or ground. Switch the multimeter leads and touch the red lead to the positive terminal of the battery, then gently touch the black lead to PIN B (black or black with a pink stripe).

Step 4: Measure the TPS Signal

If you have a trouble code related to the TPS being out of range, or if you are installing a replacement TPS, you will need to backpin the wire at terminal A. With the throttle plate closed, measure the voltage at this terminal, which should be between 0.5 to 0.9 Volt DC. Keep the ignition on and manually open the throttle body to the Wide Open Throttle (WOT) position. At WOT, the TPS sensor should transmit between 4.5 to 4.9 Volts of DC power. If the sensor does not respond with these values, it may need to be replaced.

Step 5: Check Other Potential Causes

Inconsistent power can also be caused by issues with the fuel system, such as clogged fuel filters or injectors, a malfunctioning fuel pump, or a faulty fuel pressure regulator. Additionally, problems with the ignition coil, spark plugs, air filter, mass air flow sensor, catalytic converter, or exhaust gas recirculation (EGR) valve can contribute to inconsistent power.

Check engine light is on

If the check engine light is on, this could be due to a faulty throttle position sensor (TPS). The TPS measures the position of the throttle blade and sends this data to the powertrain control module (PCM), which adjusts the amount of fuel delivered to the engine accordingly.

A faulty TPS can cause a range of issues, including:

• Lack of acceleration
• Automatic transmission performance issues
• The vehicle being stuck in limp mode

To diagnose a bad TPS, you can use a digital multimeter to check if the sensor is functioning. Here are the steps you can take:

• Check for diagnostic trouble codes (DTCs): If there is a DTC for the TP sensor stored, there is likely a problem with the sensor or its circuit.
• Perform a visual inspection: Look for issues such as damaged wires and poor connections.
• Test the TP sensor circuit: With the ignition switch turned on, test for power (reference voltage) going to the sensor. You should see around 5 volts. Then, with the ignition off, test the ground side of the circuit. A reading other than "out of limits" indicates a functioning ground side.
• Test the TP sensor: With the ignition on and the throttle closed, you should get a reading of around 0.5 volts. Manually open the throttle and check for a smooth increase in voltage to around 4.5 volts. Then, slowly close the throttle and look for a corresponding decrease in voltage. A good sensor will produce a smooth voltage change without any dropout spots.

If your Chevy Silverado is equipped with a Tire Pressure Monitoring System (TPMS), a "Service Tire Monitor System" warning may also illuminate the check engine light. This indicates that the TPMS is not working properly, or you may have under-inflated tires. In this case, check the tire pressure for all four tires and fill them back up to the recommended PSI if needed. If the tires are not losing air pressure, take your Silverado to a Chevy dealer or qualified mechanic to replace the tire pressure sensor.

Poor engine performance

A bad throttle position (TP) sensor can cause poor engine performance. The TP sensor is an input to the PCM for fuel delivery, ignition timing, and other outputs. Therefore, problems with the TP sensor can easily lead to engine performance problems, such as a lack of acceleration.

• Illuminated check engine light: The PCM monitors the TP sensor to ensure it is working properly. If it detects an issue, it will turn on the check engine light.
• Engine performance problems: As mentioned, the TP sensor plays a role in fuel delivery and ignition timing. Issues with the TP sensor can lead to poor engine performance, such as a lack of acceleration or the engine increasing speed on its own.
• Automatic transmission performance issues: The TP sensor is also an input to the control module for automatic transmission functions. A faulty sensor can cause problems such as harsh or delayed shifting.
• Vehicle stuck in "limp mode": Modern vehicles with ETC use TP sensors as a primary input for throttle control. If one of the sensors fails, the control module may put the vehicle in "limp mode" or "reduced power mode" as a safety measure.

If you suspect a bad TP sensor, it is important to perform a proper diagnosis before replacing any parts. This can be done by checking for diagnostic trouble codes, performing a visual inspection, and testing the TP sensor circuit and sensor using a digital multimeter.

Transmission performance issues

The throttle position (TP) sensor in a Chevy Silverado measures the position of the throttle blade. The TP sensor is a critical component as the Powertrain Control Module (PCM) relies on it to determine how far the throttle has opened. The PCM then adjusts how much fuel to deliver to the engine based on the TP sensor signal.

A faulty TP sensor can cause transmission performance issues, such as harsh or delayed shifting. It can also cause the vehicle to be stuck in limp mode.

To diagnose a bad TP sensor, you should first check for diagnostic trouble codes (DTCs). Then, perform a visual inspection for issues such as damaged wires and poor connections. If no issues are found, you can test the TP sensor circuit with a digital multimeter (DMM).

• Put on safety glasses.
• Consult a repair manual to identify the terminals on the throttle position sensor connector.
• Test for power (reference voltage) going to the sensor:

• Remove the electrical connector from the TP sensor.
• Turn the ignition switch ON.
• Set the DMM to the DC volts setting.
• Connect one meter lead to the battery's negative terminal and the other lead to the reference voltage terminal on the harness side of the TP sensor connector.
• If you measure around 5 volts, the reference voltage portion of the circuit is intact.

Test the ground side of the circuit:

• Set the DMM to the ohms setting.
• Connect one meter lead to the battery's negative terminal and the other lead to the ground terminal on the harness side of the motor connector.
• A reading other than "out of limits" (OL) indicates that the ground side of the circuit is functioning correctly.

If the circuit tests show no issues, you can proceed to test the TP sensor itself. Here are the steps to test the TP sensor:

• Turn the ignition switch ON, but leave the engine off.
• Keep the electrical connector connected to the TP sensor.
• Use back probe test leads to connect the DMM between the TP sensor signal wire and the ground wire.
• With the ignition on and the throttle closed, you should measure around 0.5 volts.
• Manually operate the throttle cam and slowly open the throttle.

If the sensor is working properly, the voltage signal will increase smoothly as the throttle opens.

• Once the throttle is fully open, the reading should be approximately 4.5 volts.
• Slowly return the throttle to the closed position while observing a corresponding decrease in voltage from the TP sensor.

A functional sensor will produce a smooth decrease in voltage without any dropout spots.

If the TP sensor does not respond correctly to the above tests, and the circuit tests in Step 3 indicate that the circuit is intact, the sensor is likely faulty and needs to be replaced.

Use a digital multimeter to test the sensor

To test your Chevy Silverado TPS sensor with a digital multimeter, you'll first need to turn the ignition to the "ON" position. This will power up the sensors in your engine bay. Now you can locate the throttle sensor under the hood of your Silverado. It's on the driver side of your throttle body. You can disconnect it by lifting the harness locking tab.

The three wires that make up the TPS connector are power, ground, and signal. The wire you'll be checking is the wire that leads to PIN C. This wire should be grey or grey with a red stripe on the wiring harness. Remember that you are testing the engine harness side of the Silverado TPS sensor. When testing, never force the leads into the metal clips, as this may damage or compromise the contact quality of your TPS sensor.

With the ignition turned to the "ON" position, you should read 5 volts. If you have power at this wire, the next wire to check is the wire that leads to PIN B. This is the low reference signal, or the ground sent by your PCM. To check this, switch your multimeter leads around. Put the red lead to the positive terminal on your battery and gently touch the black lead to PIN B. This wire should be black or black with a pink stripe.

If you have both power and ground at this sensor, the last step is to check the signal wire to make sure it's working correctly. Once you are ready, plug the Silverado TPS sensor harness back into the sensor. You will need to backpin the wire located at terminal A. If you don't have a backpin handy, use the red lead of your multimeter and pierce this wire.

With the throttle plate closed, you should be reading between 0.5 to 0.9-volt DC of the signal. This signal should not fluctuate but hold steady. Keep the ignition turned to the "ON" position and then manually open the throttle body. This position is known as Wide Open Throttle, and at the WOT position, the Silverado TPS Sensor should transmit between 4.5 to 4.9 volts of DC power.

If your Chevy throttle sensor does not respond with these values, it has likely gone out and needs to be replaced.

Frequently asked questions