Engine Control System - 1.8L (Lnk) - DTC P0130-P0455: Overview Pontiac Vibe I рестайлинг

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step verifies whether the malfunction is presently occurring.
3. 3: This step checks whether the malfunction that caused the DTC P0130 is still present. Operating the vehicle in Check Mode enhances the diagnostic capabilities of the PCM. The HO2S 1 diagnostic can be monitored on the scan tool under the I/M System Information selection. When the HO2S test displays a YES status, indicating that the heated oxygen sensor system diagnostic is completed, check for DTC P0130 in the Last Test Failed screen of the scan tool. If there is no DTC P0130 displayed, the HO2S diagnostic has run and passed, indicating that no malfunction was present this time. The DTCs MUST be cleared in order to view the Current Status of the system diagnostics being performed. Do not forget that the I/M System Information tests only indicate that the test has run, not whether the test passed or failed. The Last Test Failed screen must be checked for related DTCs in order to determine the outcome of the diagnostic test involved.
4. 4: In this step the DMM is used as a low current voltage source taking the place of the HO2S. This step verifies whether the PCM is able to receive and process a signal from the HO2S 1.
5. 8: A condition that affects the fuel mixture or combustion event in the engine can impact the operation of the HO2S. This can cause an accurate signal from the HO2S to fail the diagnostic. Performing the tests listed in Diagnostic Aids will eliminate a faulty running condition and prevent the replacement of a good oxygen sensor.

DTC P0130

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step checks whether the malfunction that caused the DTC P0133 is still present. Operating the vehicle in Check Mode enhances the diagnostic capabilities of the PCM. The HO2S 1 diagnostic can be monitored on the scan tool under the I/M System Information. When the HO2S test displays a YES status, indicating that the heated oxygen sensor system diagnostic is completed, check for a DTC P0133 in the Last Test Failed screen of the scan tool. If there is no DTC P0133 displayed the HO2S diagnostic has run and passed, indicating that no malfunction was present this time. The DTCs MUST be cleared in order to view the Current Status of the system diagnostics being performed. Do not forget that the I/M System Information tests only indicate that the test has run, not whether the test passed or failed. The Last Test Failed screen must be checked for related DTCs in order to determine the outcome of the diagnostic test involved.
3. 5: In this step the DMM is used as a low current voltage source taking the place of the HO2S. This step verifies whether the PCM is able to receive and process a signal from the HO2S 1.

DTC P0133

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 3: This step verifies whether the malfunction is presently occurring.
3. 4: This step checks whether the malfunction that caused the DTC P0134 is still present. Operating the vehicle in Check Mode enhances the diagnostic capabilities of the PCM. The HO2S 1 diagnostic can be monitored on the scan tool under the I/M System Information selection. When the HO2S test displays a YES status, indicating that the heated oxygen sensor system diagnostic is completed, check for DTC P0134 in the Last Test Failed screen of the scan tool. If there is no DTC P0134 displayed, the HO2S diagnostic has run and passed, indicating that no malfunction was present this time. The DTCs MUST be cleared in order to view the Current Status of the system diagnostics being performed. Do not forget that the I/M System Information tests only indicate that the test has run, not whether the test passed or failed. The Last Test Failed screen must be checked for related DTCs in order to determine the outcome of the diagnostic test involved.
4. 5: In this step the DMM is used as a low current voltage source taking the place of the HO2S. This step verifies whether the PCM is able to receive and process a signal from the HO2S 1.
5. 9: A condition that affects the fuel mixture or combustion event in the engine can impact the operation of the HO2S. This can cause an accurate signal from the HO2S to fail the diagnostic. Performing the tests listed in Diagnostic Aids will eliminate a faulty running condition and prevent the replacement of a good oxygen sensor.

DTC P0134

The numbers below refer to the step numbers in the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step checks whether the malfunction is a high input condition.
3. 3: This step determines if the DTC P0136 is the result of a hard failure or an intermittent condition.
4. 4: In this step the DMM is used as a low current voltage source taking the place of the HO2S. If the HO2S 2 input circuit and the PCM are good, the scan tool will display approximately 1,275 mV.

DTC P0136

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 3: Visually and physically checking items that may cause a lean condition that may determine the reason that the DTC set.
3. 4: Engine control sensors that are found to be out range (skewed) or fixed, can cause the engine to run lean. Inspect the performance of the MAF sensor. Inspect for air restrictions and air inlet leaks near the MAF sensor. If the HO2S voltage is fixed low, while the fuel trim is constantly high, check the MAF sensor signal circuit for resistance. High circuit resistance can cause the sensor to read a lower volume of air than actual, resulting in a lean fueling condition. Refer to the applicable sensor DTC table for direction in diagnosing any possible sensor error.
4. 6: Contaminants in the fuel, such as alcohol or water, can create a lean condition and set DTC P0171. Small amounts of water delivered to the fuel injectors and cause a lean exhaust indication. A lean exhaust indication can also be caused by too much alcohol in the fuel.

DTC P0171

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 3: A plugged air filter can cause a rich condition and set a DTC P0172.
3. 4: Engine control sensors that are found to be out range (skewed) or fixed, can cause the engine to run rich. Inspect the performance of the MAF sensor. Inspect for air restrictions and air inlet leaks near the MAF sensor. If the HO2S voltage is fixed low, while the fuel trim is constantly high, check the MAF sensor circuits for resistance. High circuit resistance can cause the sensor to read the incorrect volume of air, resulting in the wrong fueling condition. Refer to the applicable sensor DTC table for direction in diagnosing any possible sensor error.

DTC P0172

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 3: This step verifies whether the misfire is present. The scan tool will display increasing counts in the Total Misfire Current Count parameter if a misfire is occurring.
3. 4: This step checks whether the DTC P0300 is the result of a hard failure or an intermittent condition. Operating the vehicle in Check mode enhances the diagnostic capabilities of the PCM. For additional information on Check mode operation, refer to the Powertrain Control Module Diagnosis. The scan tool will display increasing counts in the Total Misfire Current Count parameter if a misfire is occurring.
4. 5: This step tests for adequate secondary ignition voltage. The fuel injectors are disabled in order to prevent unburned fuel from accumulating in the cylinders.
5. 7: This step inspects for a condition that can reduce the secondary ignition voltage to the spark plug. Step 6 verified that the ignition coil output is satisfactory, this step will qualify the remaining secondary ignition system components.
6. 12: Contaminants in the fuel, such as alcohol or water, can create a misfire condition.
7. 13: A vacuum leak can cause a lean misfire condition.

DTC P0300

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step verifies whether the misfire is present. The scan tool will display increasing counts in the Misfire Current Cyl. # parameter of the misfiring cylinder when a misfire is occurring.
3. 3: This step checks whether the MIL is the result of a hard failure or an intermittent condition. Operating the vehicle in check mode enhances the diagnostic capabilities of the PCM. The scan tool will display increasing counts in the Misfire Current Cyl. # data parameter of the cylinder that is experiencing a misfire.
4. 4: Fault not present indicates that the condition that caused the DTC P0301-P0304 to set is intermittent and not currently present. If no other DTCs are stored, refer to Diagnostic Aids for additional information on diagnosing an intermittent DTC P0301-P0304.
5. 5: This step is to verify if the misfire is caused by a fault in the primary circuit of the ignition system.
6. 13: Contaminants in the fuel, such as alcohol or water, can create a misfire condition.
7. 14: A vacuum leak can cause a lean misfire condition.

DTC P0301-P0304

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step verifies whether the DTC P0325 is the result of a hard failure or an intermittent condition. Operating the vehicle in Check Mode enhances the diagnostic capabilities of the PCM.
3. 4: This step verifies the resistance of the KS.
4. 5: This step verifies the knock sensors ability to output the correct frequency signal for a given engine speed.

DTC P0325

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check-Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 3: This step verifies the resistance of the KS.

DTC P0327

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check-Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step verifies whether the DTC P0328 is the result of a hard failure or an intermittent condition. Operating the vehicle in Check Mode enhances the diagnostic capabilities of the PCM.
3. 4: This step verifies the resistance of the KS.
4. 5: This step verifies the knock sensors ability to output the correct frequency signal for a given engine speed.

DTC P0328

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 3: This step determines whether the DTC P0335 is the result of a hard failure or an intermittent condition. If the engine will not start, crank the engine over 3 consecutive ignition cycles (key ON-key OFF).
3. 5: This step verifies the internal resistance of the crankshaft position sensor. A typical value at 23°C (74°F) is 2.1k ohms.
4. 6: This step tests the CKP sensor output signal and electrical circuit to the PCM.
5. 7: This step determines which half of the CKP sensor circuit is faulty.
6. 11: This step inspects for a faulty signal rotor. Visually inspect the teeth of the signal rotor through the CKP sensor aperture for damage, foreign material, and mis-alignment.

DTC P0335

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 3: This step determines whether the DTC P0339 is the result of a hard failure or an intermittent condition. If engine will not start, crank the engine over 3 consecutive ignition cycles (key ON-key OFF).
3. 5: This step verifies the internal resistance of the crankshaft position sensor. A typical value at 23°C (74°F) is 2.1K ohms.
4. 6: This step tests the CKP sensor output signal and electrical circuit to the PCM.
5. 7: This step determines which half of the CKP sensor circuit is faulty.
6. 11: This step inspects for a faulty signal rotor. Visually inspect the teeth of the signal rotor through the CKP sensor aperture for damage, foreign material, and mis-alignment.

DTC P0339

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step tests for an open in the ground circuit of the CMP sensor from PCM connector C1 terminal 34 to SP108. The engine will not stay running and DTC P0340 will set if the CMP sensor and CKP sensor ground circuit is open.
3. 3: This step determines if DTC P0340 is the result of a hard failure or an intermittent condition.
4. 5: This step verifies the internal resistance of the camshaft position sensor. A typical value at 23°C (74°F) is 1.1K ohms.
5. 6: This step verifies the CMP sensor output signal. The CMP sensor sends the PCM one electrical pulse for every revolution of the intake camshaft. Therefore, the AC signal generated by the CMP sensor will be numerically analogous to the engine speed. With the engine speed at about 1,200 RPM, the CMP sensor voltage should be around 2.45-2.55 volts AC.
6. 8: This step tests the CMP` input circuit to the PCM. The AC signal generated by the CMP sensor will be numerically analogous to the engine speed. With the engine speed at about 1,200 RPM, the CMP sensor voltage should be around 2.45-2.55 volts AC. The CMP sensor signal wire must be removed from the PCM connector in order to accurately check the sensor output. If the CMP sensor signal wire is backprobed while connected to the PCM, the AC voltage indicated on a DMM will be approximately 15-20 percent lower than the actual engine speed.
7. 12: This step inspects for a faulty signal rotor on the camshaft. Visually inspect the tooth of the signal rotor through the CMP sensor aperture for damage, foreign material, and installation.

DTC P0340

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step tests for an open in the ground circuit of the CMP sensor from PCM connector C1 terminal 34 to SP108. The engine will not stay running and DTC P0341 will set if the CMP sensor and CKP sensor ground circuit is open.
3. 3: This step determines if DTC P0341 is the result of a hard failure or an intermittent condition.
4. 5: This step verifies the internal resistance of the camshaft position sensor. A typical value at 23°C (74°F) is 1.1K ohms.
5. 6: This step verifies the CMP sensor output signal. The CMP sensor sends the PCM one electrical pulse for every revolution of the intake camshaft. Therefore, the AC signal generated by the CMP sensor will be numerically analogous to the engine speed. With the engine speed at about 1,200 RPM, the CMP sensor voltage should be around 2.45-2.55 volts AC.
6. 8: This step tests the CMP input circuit to the PCM. The AC signal generated by the CMP sensor will be numerically analogous to the engine speed. With the engine speed at about 1,200 RPM, the CMP sensor voltage should be around 2.45-2.55 volts AC. The CMP sensor signal wire must be removed from the PCM connector in order to accurately check the sensor output. If the CMP sensor signal wire is backprobed while connected to the PCM, the AC voltage indicated on a DMM will be approximately 15-20 percent lower than the actual engine speed.
7. 12: This step inspects for a faulty signal rotor on the camshaft. Visually inspect the tooth of the signal rotor through the CMP sensor aperture for damage, foreign material, and installation.

DTC P0341

The numbers below refer to the step numbers in the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: If DTCs P0351, P0352, P0353, and P0354 are present, the fault is located in the shared electrical circuits or shared components of the ignition coils.
3. 3: If there is no engine misfire present, there is a fault in the Ignition Fail-Safe Input signal circuit.
4. 4: DTC P0351 indicates a failure in the circuits of ignition coil 1. DTC P0352 indicates a fault with ignition coil 2. DTC P0353 indicates a fault with ignition coil 3. DTC P0354 indicates a fault with ignition coil 4.
5. 5: This step tests for an open or a short in the ignition trigger signal circuit. The voltage on the ignition trigger signal circuit will fluctuate very quickly when starting or running the engine. The DMM voltage reading on the ignition trigger signal circuit should indicate 0.2-1 volt. Using the min/max feature on the DMM may indicate a maximum voltage as high as 3.5 volts.
6. 11: This step tests for a fault in the Ignition Fail-Safe Input circuit. If the cause of the DTCs P0351, P0352, P0353, and P0354 is a fault in the ignition fail-safe input circuit, the engine will start and run for less than 2 seconds. Without the fail-safe signal the PCM will initiate fuel cutoff.
7. 13: This step tests for a short in the ignition positive voltage supply to the ignition coils or for a faulty noise filter. A shorted noise filter may pull down the ignition coil primary voltage.

DTC P0351-P0354

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 3: This step verifies whether the malfunction is presently occurring.
3. 4: This step checks whether the malfunction that caused the DTC P0420 is still present. The catalytic converter diagnostic can be monitored on the scan tool under the I/M System Information. When the Catalyst test displays a YES status, indicating that the catalytic converter diagnostic is completed, check for DTC P0420 in the Last Test Failed screen of the scan tool. If there is no DTC P0420 displayed the Catalyst diagnostic has run and passed, indicating that no malfunction was present this time. DTCs MUST be cleared in order to view the Current Status of the system diagnostics being performed. Do not forget that the I/M System Information tests only indicate that the test has run, not if the test passed or failed. The Last Test Failed screen must be checked for related DTCs in order to determine the outcome of the diagnostic test involved.

DTC P0420

System Description

The diagnostic strategy for the evaporative emission (EVAP) system uses a vacuum pump to test for system leaks, after the engine is OFF. A unique fuel tank, EVAP canister, and EVAP vacuum leak pump work together to provide enhanced system diagnosis. The vacuum leak pump, the fuel tank pressure (FTP) sensor and the EVAP canister vent valve are all integral parts of one assembly. The assembly is attached directly to the EVAP canister, located near the fuel tank.

After the vehicle has sat with the engine OFF for about 5 hours, a comprehensive diagnostic is enabled with no operator input necessary. The complete test can take up to 15 minutes to run, with leak detection comprising the largest portion of the test. For more detailed information on the EVAP system components and diagnostic theory, refer to Evaporative Emission (EVAP) Control System Description.

The numbers below refer to the step numbers on the diagnostic table.

1. 2: In order to correctly identify the malfunction, DTC P2401, P2402, and P2419 must be diagnosed before DTC P043E or P043F.
2. 5: This step uses the EVAP Service Bay test in order to verify the correct operation of the EVAP vent solenoid, the EVAP purge solenoid, and the EVAP vacuum leak pump. Using the Service Bay test also tests for leaks by sealing the system and monitoring the FTP sensor.

DTC P043E

The diagnostic strategy for the evaporative emission (EVAP) system uses a vacuum pump to test for system leaks, after the engine is OFF. A unique fuel tank, EVAP canister, and EVAP vacuum leak pump work together to provide enhanced system diagnosis. The vacuum leak pump, the fuel tank pressure (FTP) sensor and the EVAP canister vent valve are all integral parts of one assembly. The assembly is attached directly to the EVAP canister, located near the fuel tank.

After the vehicle has sat with the engine OFF for about 5 hours, a comprehensive diagnostic is enabled with no operator input necessary. The complete test can take up to 15 minutes to run, with leak detection comprising the largest portion of the test. For more detailed information on the EVAP system components and diagnostic theory, refer to Evaporative Emission (EVAP) Control System Description.

The numbers below refer to the step numbers on the diagnostic table.

1. 2: In order to correctly identify the malfunction, DTC P2401, P2402, and P2419 must be diagnosed before DTC P043E or P043F.
2. 5: This step uses the EVAP Service Bay test in order to verify the correct operation of the EVAP vent solenoid, the EVAP purge solenoid, and the EVAP vacuum leak pump. Using the Service Bay test also tests for leaks by sealing the system and monitoring the FTP sensor.

DTC P043F

The DTC P0441 Evaporative Emission (EVAP) System No Flow During Purge diagnostic monitors the changes in the vacuum pressure in the fuel tank. The diagnostic strategy for the EVAP system uses a vacuum pump to test for system leaks, after the engine is OFF. A unique fuel tank, EVAP canister, and EVAP vacuum leak pump work together to provide enhanced system diagnosis. The vacuum leak pump, the fuel tank pressure (FTP) sensor and the EVAP canister vent valve are all integral parts of one assembly. The assembly is attached directly to the EVAP canister, located near the fuel tank.

After the vehicle has sat with the engine OFF for about 5 hours, a comprehensive diagnostic is enabled with no operator input necessary. The complete test can take up to 15 minutes to run, with leak detection comprising the largest portion of the test. If the PCM detects the vacuum level was not achieved, DTC P0441 will set. For more detailed information on the EVAP system components and diagnostic theory, refer to Evaporative Emission (EVAP) Control System Description.

The numbers below refer to the step numbers on the diagnostic table.

1. 2: This step verifies that the DTC P0441 is captured in the Freeze Frame/Failure Record list. When multiple EVAP system DTCs are set, the DTC stored in the Freeze Frame/Failure Record is the best diagnostic starting point.
2. 3: This step verifies the electrical operation of the EVAP canister purge solenoid.
3. 4: This step tests the function of the EVAP canister purge solenoid.
4. 7: This step uses the EVAP Service Bay test in order to verify the correct operation of the EVAP canister purge solenoid and the other EVAP system components. Performing the EVAP Service Bay test also tests for EVAP system leaks.
5. 18: This step tests for a blockage or a restriction in the purge port and purge passages located in the EVAP canister assembly. If the purge passage is blocked or restricted, the EVAP system diagnostic can fail and set this DTC.
6. 19: This step uses the EVAP Service Bay test in order to verify the correct operation of the EVAP canister purge solenoid and the EVAP vacuum leak pump assembly. Performing the EVAP Service Bay test also tests for EVAP system leaks.

DTC P0441

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step determines if a FTP sensor malfunction is present. The input signal of the FTP sensor should indicate atmospheric pressure with the fuel tank filler cap removed. The fuel tank pressure sensor voltage will vary with atmospheric pressure. A typical FTP reading at sea level is between 3.5-3.8 volts.
3. 3: This step determines if DTC P0450 is the result of a hard failure or an intermittent condition. Operating the vehicle in the Check Mode enhances the diagnostic capabilities of the PCM.
4. 4: This step checks whether there is trapped negative or positive pressure at the FTP sensor.
5. 6: This step checks for an open or a short in the FTP sensor 5-volt reference.
6. 7: The FTP sensor signal circuit carries a 5 volt bias that can be measured with the DMM. If the voltage is near zero there is an open, a short to ground, or a faulty PCM.
7. 10: This step checks for an open in the FTP sensor ground circuit.

DTC P0450

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step determines if a FTP sensor malfunction is present. The output voltage of the FTP sensor should indicate atmospheric pressure with the fuel tank filler cap removed. The FTP sensor voltage will vary with atmospheric pressure. A typical voltage at sea level is between 3.5-3.8 volts.
3. 3: This step determines if DTC P0451 is the result of a hard failure or an intermittent condition. Operating the vehicle in Check mode enhances the diagnostic capabilities of the PCM.
4. 4: This step determines if there is trapped negative or positive pressure at the FTP sensor.
5. 6: This step inspects for an open or a short in the FTP sensor 5-volt reference.
6. 7: This step inspects for excessive resistance in the reference voltage circuit. If the test lamp does not illuminate at all, there is resistance in the circuit.
7. 9: This step checks for an open or short in the FTP sensor input circuit.
8. 11: This step checks for an open in the FTP sensor ground circuit.

DTC P0451

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step determines if a FTP sensor malfunction is present. The input signal of the FTP sensor should indicate atmospheric pressure with the fuel tank filler cap removed. The fuel tank pressure sensor voltage will vary with atmospheric pressure. A typical FTP reading at sea level is between 3.5-3.8 volts.
3. 5: This step checks for an open in the FTP sensor reference voltage circuit.
4. 6: The FTP sensor signal circuit carries a 5 volt bias that can be measured with the DMM. If the measured voltage is near zero there is a short to ground or a faulty PCM.
5. 12: The EVAP system diagnostic can be monitored on the scan tool under the I/M System Information selection. When the EVAP test displays a YES status, indicating that the system diagnostic is completed, check for DTC P0452 in the Last Test Failed screen of the scan tool. If there is no DTC P0452 displayed the EVAP system diagnostic has run and passed, indicating that no malfunction was present this time. DTCs MUST be cleared in order to view the Current Status of the system diagnostics being performed. Do not forget that the I/M System Information tests only indicate that the test has run, not if the test passed or failed. The Last Test Failed screen must be checked for related DTCs in order to determine the outcome of the diagnostic test involved.

DTC P0452

The numbers below refer to the step numbers on the diagnostic table.

1. 1: The Diagnostic System Check- Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2: This step determines if a FTP sensor malfunction is present. The input signal of the FTP sensor should indicate atmospheric pressure with the fuel tank filler cap removed. The fuel tank pressure sensor voltage will vary with atmospheric pressure. A typical FTP reading at sea level is between 3.5-3.8 volts.
3. 5: The FTP sensor signal circuit carries a 5 volt bias that can be measured with the DMM. If the measured voltage is near zero there is an open or a faulty PCM.
4. 7: This step checks for an open in the FTP sensor ground circuit.
5. 12: The EVAP system diagnostic can be monitored on the scan tool under the I/M System Information selection. When the EVAP test displays a YES status, indicating that the system diagnostic is completed, check for DTC P0453 in the Last Test Failed screen of the scan tool. If there is no DTC P0453 displayed the EVAP system diagnostic has run and passed, indicating that no malfunction was present this time. DTCs MUST be cleared in order to view the Current Status of the system diagnostics being performed. Do not forget that the I/M System Information tests only indicate that the test has run, not if the test passed or failed. The Last Test Failed screen must be checked for related DTCs in order to determine the outcome of the diagnostic test involved.

DTC P0453

The DTC P0455 Evaporative Emission (EVAP) System Large Leak Detected diagnostic detects evaporative emission system leaks as small as 1.0 mm (0.040 in). The diagnostic strategy for the EVAP system uses a vacuum pump to test for system leaks after the engine is OFF. A unique fuel tank, EVAP canister, and EVAP vacuum leak pump, work together in order to provide enhanced system diagnosis. The vacuum leak pump, the fuel tank pressure (FTP) sensor and the EVAP canister vent valve are all integral parts of one assembly. The assembly is attached directly to the EVAP canister, located near the fuel tank.

After the vehicle has sat with the engine OFF for about 5 hours, a comprehensive diagnostic is enabled with no operator input necessary. The complete test can take up to 15 minutes to run, with leak detection comprising the largest portion of the test. If a specified minimum value of vacuum pressure is not achieved, a DTC P0455 will set. For more detailed information on the EVAP system components and diagnostic strategy, refer to Evaporative Emission (EVAP) Control System Description.

The numbers below refer to the step numbers on the diagnostic table.

1. 2: If there any other EVAP system DTCs set, repair those DTCs first.
2. 5: Waiting until smoke is seen before plugging the EVAP canister vent line speeds up the filling of the canister and fuel tank with smoke. Introducing smoke in between 60 second intervals of Nitrogen also increases the speed of the filling of smoke in the fuel tank, the filler pipe vapor space, and the EVAP canister. This occurs because the pressure at which Nitrogen gas is applied is greater than the pressure at which smoke is introduced. The Nitrogen gas pushes the smoke that was just introduced through the canister and into the fuel tank. The EVAP vent solenoid DOES NOT have to be turned ON in order to test for leaks. The installation of the 41413-324 adapter into the EVAP air filter line seals the tank side of the EVAP system.
3. 7: This test verifies that the FTP sensor is accurate. The FTP sensor should indicate little or no pressure with fuel fill pipe open. An FTP sensor that does not correctly respond to vacuum, or pressure may cause this DTC to set.
4. 8: This step tests the operation of the EVAP vent solenoid located in the EVAP vacuum leak pump assembly. If the vent solenoid passage leaks, or is blocked, the EVAP system leak diagnostic will fail and set a DTC. If the 0.51 mm (0.020 in) reference orifice in the vacuum leak pump assembly is restricted, a DTC can set. These internal leaks and restrictions are not detected using the J 41413-200 EEST, but can set this DTC.
5. 9: This step tests for a blockage or a restriction in the air inlet passage to the EVAP vent solenoid located in the vacuum leak pump assembly. This type of blockage or restriction is not detected using the J 41413-200 EEST, but can set this DTC.
6. 10: This step verifies whether a leak in the EVAP system still exists. If the flow gage on the EEST and/or the scan tool pressure reading remain constant, there is no external leak. If the EEST gage indicates flow, or the scan tool pressure reading decreases, there is still an external leak in the EVAP system.
7. 11: This step uses the EVAP Service Bay test in order to verify the correct operation of the EVAP canister purge solenoid, vent solenoid, and the other EVAP system components. Performing the EVAP Service Bay test also tests for EVAP system leaks.

DTC P0455

See also:
• Scan Tool Data List
• Scan Tool Output Controls