DTC P0101. Chevrolet Chevy K Silverado

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2003 🢒 Chevy K Silverado - 4WD 🢒 DTC 🢒 DTC P0101

Circuit Description

The mass air flow (MAF) sensor is an air flow meter that measures the amount of air entering the engine. The engine control module (ECM) uses the MAF sensor voltage signal to provide the correct fuel delivery for a reduction in emissions. The ECM uses the MAF sensor signal to control fuel delivery until a calibrated amount of engine air flow is attained. The MAF sensor has an ignition 1 voltage circuit, a signal circuit and a low reference circuit. The MAF sensor produces an output voltage based on the inlet air flow through the air induction system. This output voltage will display on the scan tool as a grams per second (g/s) value. The ECM will calculate a predicted MAF value. The ECM compares the actual MAF sensor voltage signal to the predicted MAF value. This comparison will determine if the signal is stuck, or is too low or too high for a given operating condition. If the ECM detects that the actual MAF sensor voltage signal is not within a predetermined range of the calculated MAF value DTC P0101 sets.

Conditions for Running the DTC

•	DTC P0016, P0102, P0103, P0112, P0113, P0234, P0236, P0237, P0238, P0335, P0336, P2227, P2228, P2229 are not set.

•	The ignition 1 signal is between 9-18 volts.

•	The engine speed is less than 2,500 RPM.

•	The engine speed is steady within a range of 50 RPM.

•	The accelerator pedal position (APP) indicated angle is less than 50 percent.

•	The above conditions are met for more than 2 seconds.

Conditions for Setting the DTC

The ECM detects that the actual MAF sensor voltage signal is not within a predetermined range of the calculated MAF value for more than 2 seconds.

Action Taken When the DTC Sets - California

•	The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.

•

The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Action Taken When the DTC Sets - Federal

•	The control module stores the DTC information into memory when the diagnostic runs and fails.

•	The MIL will not illuminate.

•	The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.

•	The driver information center, if equipped, may display a message.

Conditions for Clearing the MIL/DTC - California

•	The control module turns OFF the MIL after 3 consecutive ignition cycles that the diagnostic runs and does not fail.

•	A current DTC, Last Test Failed, clears when the diagnostic runs and passes.

•	A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.

•	Use a scan tool in order to clear the MIL and the DTC.

Conditions for Clearing the DTC - Federal

•	A current DTC, Last Test Failed, clears when the diagnostic runs and passes.

•	A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.

•	Use a scan tool in order to clear the MIL and the DTC.

Diagnostic Aids

Inspect for the following conditions:

•	Any unmetered air--Any unmetered air that enters the engine downstream of the MAF sensor may cause this DTC to set.

•	A sluggish or unresponsive MAF sensor--A short between the signal circuit of the MAF sensor and the signal circuit of the intake air temperature (IAT) sensor. This will cause the MAF sensor to have a very limited output voltage range.

•	A malfunctioning MAF sensor can cause excessive engine emissions.

•	An open on the 5-volt reference circuit of the barometric pressure (BARO) sensor may cause this DTC to set.

•	A short to ground on the signal circuit of the BARO sensor may cause this DTC to set.

•	The signal circuit of the BARO sensor shorted to 5 volts may cause this DTC to set.

•	An open signal circuit of the BARO sensor may cause this DTC to set.

•	The MAF display should increase from 42-50 g/s at idle to 420 g/s or more at the 2-3 shift during a wide-open throttle (WOT) acceleration. If not, inspect for a restriction in the induction system or the exhaust system.

•	If the vehicle condition is intermittent, refer to Intermittent Conditions .

Step

Action

Values

Yes

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views

Did you perform the Diagnostic System Check - Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

Start the engine
Monitor the Diagnostic Trouble Code (DTC) Information using the scan tool.

Does the scan tool display any other DTCs set?

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

Observe the Freeze Frame/Failure Records for this DTC.
Turn OFF the ignition for 30 seconds.
Start the engine.
Operate the vehicle within the Conditions for Running the DTC . You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

Go to Step 4

Go to Diagnostic Aids

Inspect the fuse in the ignition 1 voltage circuit of the mass air flow (MAF) sensor.

Is the fuse open?

Go to Step 17

Go to Step 5

Turn OFF the ignition.
Inspect for air leaks in the following components:

•	A damaged MAF Sensor housing

•	The air induction system and the turbocharger system

•	The charge air cooler with a J 46091 Charge Air Cooler Tester

•	The MAF sensor O-ring seal

•	The boost pressure sensor seal

•	The exhaust gas recirculation (EGR) throttle valve solenoid , diaphragm, or vacuum hose

•	The EGR valve solenoid valve diaphragm, or vacuum hose

•	The EGR vent solenoid or vacuum hose

Inspect for the following conditions:

•	Any kinks or restrictions in any of the EGR solenoid vacuum hoses

•	An obstructed intake air duct or a dirty air filter element

•	Any debris that is blocking the air sensing filaments of the MAF sensor

•	Any water intrusion in the air induction system

•	A MAF sensor that is installed backwards

•	A restricted exhaust system--Refer to Restricted Exhaust in Engine Exhaust.

Did you find and correct the condition?

Go to Step 26

Go to Step 6

Turn ON the ignition, with the engine OFF.
Observe both the BARO kPa and the boost pressure sensor kPa with a scan tool.

Is the difference between the sensors equal to or less than the specified value?

4 kPa

Go to Step 7

Go to DTC P2227

Start the engine and allow the engine to idle.
Observe the MAF Sensor g/s with a scan tool.
Move the harness and the connector of the MAF sensor.

Does the movement of the harness or the connector affect the MAF sensor g/s?

Go to Step 21

Go to Step 8

Observe the MAF Sensor parameter with a scan tool.

Is the MAF Sensor parameter less than the specified value?

16 g/s

Go to Step 11

Go to Step 9

Observe the MAF Sensor parameter with a scan tool.

Is the MAF Sensor parameter more than the specified value?

445 g/s

Go to Step 10

Go to Step 11

Disconnect the harness connector of the MAF sensor.

Is the MAF Sensor parameter more than the specified value?

445 g/s

Go to Step 15

Go to Step 11

Turn OFF the engine.
Turn ON the ignition, with the engine OFF.
Disconnect the harness connector of the MAF sensor.
Connect a test lamp between the ignition 1 voltage circuit of the MAF sensor and a good ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

Go to Step 12

Go to Step 17

Important: All electrical components and accessories must be turned OFF.

Turn OFF the ignition for 60 seconds to allow the control modules to power down.
Measure the resistance from the ground circuit of the MAF sensor to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems.

Is the resistance less than the specified value?

5 ohms

Go to Step 13

Go to Step 18

Turn ON the ignition, with the engine OFF.
Connect a 3-amp fused jumper wire between the signal circuit of the intake air temperature (IAT) sensor and the signal circuit of the MAF sensor.
Observe the MAF sensor parameter with a scan tool.

Is the MAF sensor value more than the specified value?

445 g/s

Go to Step 22

Go to Step 14

Turn OFF the ignition.
Disconnect the fused jumper wire.
Disconnect the engine control module (ECM).
Test the signal circuit between the ECM and the MAF sensor for the following conditions:

•	A high resistance or an open

•	A short to ground

•	A short to the low reference circuit of the MAF sensor or IAT sensor--Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 26

Go to Step 16

Important:: Disconnecting the ECM connectors may eliminate the short to voltage if the signal circuit is shorted to another ECM circuit.

Turn OFF the ignition.
Disconnect the ECM.
Turn ON the ignition, with the engine OFF.
Measure the voltage from the signal circuit of the MAF sensor to a good ground. Refer to Circuit Testing in Wiring Systems.

Is the voltage near the specified value?

0 V

Go to Step 16

Go to Step 19

Test for continuity at the harness connector of the ECM from the signal circuit of the MAF sensor to all other circuits at both ECM connectors with a DMM. Refer to Circuit Testing in Wiring Systems.

Does the DMM indicate continuity between any other circuit?

Go to Step 20

Go to Step 23

Repair the short to ground or an open in the ignition 1 voltage circuit of the MAF sensor. Refer to Wiring Repairs in Wiring Systems.
Replace the fuse if necessary.

Did you complete the repair?

Go to Step 26

Go to Step 24

Repair the high resistance or an open in the low reference circuit of the MAF sensor. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 26

Go to Step 23

Repair the short to voltage in the signal circuit of the MAF sensor. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 26

Repair the circuits that are shorted together. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 26

Repair the harness or the connections as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 26

Inspect for poor connections at the harness connector of the MAF sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 26

Go to Step 24

Inspect for poor connections at the harness connector of the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 26

Go to Step 25

Replace the MAF/IAT sensor. Refer to Mass Airflow Sensor/Intake Air Temperature Sensor Replacement .

Did you complete the Replacement?

Go to Step 26

Replace the ECM. Refer to Engine Control Module Replacement .

Did you complete the Replacement?

Go to Step 26

With a scan tool clear the DTCs.
Turn OFF the ignition for 30 seconds.
Start the engine.
Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

Go to Step 2

Go to Step 27

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK