Engine Controls - 8.1l (DTC p0200 to p0507) Chevrolet Cab & Chassis Silverado 3500

Circuit Description

The powertrain control module (PCM) enables the appropriate fuel injector on the intake stroke for each cylinder. An ignition voltage is supplied to the fuel injectors. The PCM controls each fuel injector by grounding the control circuit via a solid state device called a driver. The PCM monitors the status of each driver. If the PCM detects an incorrect voltage for the commanded state of the driver, a fuel injector control DTC sets.

DTC Descriptor

This diagnostic procedure supports the following DTC

DTC P0200 Injector Control Circuit

Conditions for Running the DTC

1. The engine speed is more than 400 RPM.
2. The ignition voltage is between 6-18 volts.

Conditions for Setting the DTC

1. The PCM detects an incorrect voltage on a fuel injector control circuit.
2. The condition exists for 5 seconds.

Action Taken When the DTC Sets

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

Conditions for Clearing the MIL/DTC

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

Diagnostic Aids

1. Performing the Fuel Injector Coil test may help isolate an intermittent condition. Refer to «Fuel Injector Coil Test»(/chevrolet/cab-chassis-silverado-3500/2004-2007/remont/testing-diagnostics/#engine-controls-81l-troubleshooting-diagnosis) .
2. For an intermittent condition, refer to «Testing for Intermittent Conditions and Poor Connections»(ref-197325-S02683201702005101100000) in Wiring Systems.

Test Description

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

1. 4: This step tests for voltage at the fuel injector harness connector. The INJ fuse supplies power to the coil side of the fuel injector harness connector. If the fuse is open, a short to ground on the fuel injector B+ supply circuit is indicated.
2. 5: This step verifies that the PCM is able to control the fuel injector. If the test lamp blinks, then the PCM and wiring are OK.
3. 6: This step tests if a ground is constantly being applied to the fuel injector.

DTC P0200

The throttle position (TP) sensor 2 is a potentiometer type sensor with 3 circuits

1. A 5-volt reference circuit
2. A low reference circuit
3. A signal circuit

The TP sensor is used to determine the throttle plate angle for various engine management systems. The control module provides the TP sensor with a 5-volt reference circuit and a low reference circuit. The TP sensor then provides the control module with a signal voltage proportional to throttle plate movement. TP sensor 1 signal voltage is low at closed throttle and increases as the throttle opens. When the control module detects that the TP sensor 2 signal or TP sensor 5-volt reference voltage is outside the predetermined range, this DTC sets.

This diagnostic procedure supports the following DTC

DTC P0220 Throttle Position (TP) Sensor 2 Circuit

1. DTCs U0107 or P2108 are not set.
2. The ignition switch is in the crank or run position.
3. The ignition voltage is more than 5.23 volts.
4. This diagnostic runs continuously when the above conditions are met.

1. The TP sensor 2 voltage is less than 0.28 volt or greater than 4.60 volts.
2. The above condition is present for more than 1 second.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode.
4. A message center or an indicator displays Reduced Engine Power.
5. Under certain conditions the control module commands the engine OFF.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Inspect the throttle actuator control (TAC) module connectors for signs of water intrusion. If water intrusion occurs, multiple DTCs may set without any circuit or component conditions found during diagnostic testing.
2. When the TAC module detects a condition within the TAC System, more than one TAC System related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing one individual condition may correct more than one DTC. Disconnecting components during testing may set additional DTCs. Remember this if you review the stored information in Capture Info.
3. If this DTC is determined to be intermittent, refer to «Testing for Intermittent Conditions and Poor Connections»(ref-197325-S02683201702005101100000) .

The number below refers to the step number on the diagnostic table.

1. 31: When the TAC module detects a condition within the TAC System, more than one TAC System related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing one individual condition may correct more than one DTC. Disconnecting components during testing may set additional DTCs. Keep this in mind when reviewing the stored information, Capture Info.

DTC P0220

The powertrain control module (PCM) provides ignition positive voltage to the coil side of the fuel pump relay. When the ignition switch is first turned ON, the PCM energizes the fuel pump relay, which applies power to the fuel pump. The PCM enables the fuel pump relay as long as the engine is cranking or running, and crankshaft reference pulses are received. If no crankshaft reference pulses are received, the PCM de-energizes the fuel pump relay after 2 seconds. The PCM monitors the voltage on the fuel pump relay control circuit. If the PCM detects an incorrect voltage on the fuel pump relay control circuit, DTC P0230 sets.

This diagnostic procedure supports the following DTC

DTC P0230 Fuel Pump Relay Control Circuit

1. The engine speed is more than 400 RPM.
2. The ignition voltage is between 6-18 volts.

1. The PCM detects that the commanded state of the driver and the actual state of the control circuit do not match.
2. All the above conditions are present for a minimum of 2.5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

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

1. 2: Listen for a click when the fuel pump relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
2. 4: This step verifies that the PCM is providing voltage to the fuel pump relay.
3. 5: This step tests for an open in the ground circuit to the fuel pump relay.
4. 6: This step tests if voltage is constantly being applied to the control circuit of the fuel pump relay.

DTC P0230

System Description

The powertrain control module (PCM) uses information from the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor in order to determine when an engine misfire is occurring. By monitoring variations in the crankshaft rotation speed for each cylinder, the PCM is able to detect individual misfire events. A misfire rate that is high enough can cause the 3-way catalytic converter (TWC) to overheat under certain driving conditions. The malfunction indicator lamp (MIL) will flash ON and OFF when the conditions for TWC overheating are present. If the PCM detects a misfire rate sufficient to cause emission levels to exceed mandated standards, DTC P0300 will set.

This diagnostic procedure supports the following DTC

DTC P0300 Engine Misfire Detected

1. DTC P0101, P0102, P0103, P0106, P0107, P0108, P0116, P0117, P0118, P0125, P0128, P0220, P0315, P0335, P0336, P0341, P0342, P0343, P0721, P0722, P1114, P1115, P1120, P1258 are not set.
2. The engine speed is between 450-5,000 RPM.
3. The ignition voltage is between 10-18 volts.
4. The engine coolant temperature (ECT) is between -7 and +130°C (19-266°F).
5. The fuel level is more than 10 percent.
6. The throttle angle is steady within 1 percent.
7. The Antilock Brake System (ABS) and the Traction Control System (TCS) are not active.
8. The transmission is not changing gears.
9. The A/C clutch is not changing states.
10. The PCM is not in fuel shut-off or decel fuel cut-off mode.
11. The PCM is not receiving a rough road signal.
12. This diagnostic runs continuously when the above conditions are met.

The PCM is detecting a crankshaft rotation speed variation indicating a misfire sufficient to cause emission levels to exceed mandated standards.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Excessive vibration from sources other than the engine could cause DTC P0300 to set. The following are possible sources of vibration: Variable thickness brake rotors-Refer to «Symptoms - Hydraulic Brakes»(/chevrolet/cab-chassis-silverado-3500/2004-2007/remont/mechanical-hydraulic/#hydraulic-brake-system__symptoms-hydraulic-brakes) in Hydraulic Brakes. Drive shaft not balanced-Refer to «Vibration Analysis - Driveline»(ref-197433-S23292295772005101100000) in Vibration Diagnosis and Correction. Worn or damaged accessory drive belt-Refer to «Symptoms - Engine Mechanical»(/chevrolet/cab-chassis-silverado-3500/2004-2007/remont/mechanical/#engine-mechanical-81l) in Engine Mechanical.
2. There may be more or less cylinders actually misfiring than indicated by the scan tool.
3. Spray water on the secondary ignition components using a spray bottle. Look and listen for arcing or misfiring.
4. If there are multiple misfires on only one bank, inspect the fuel injector and ignition coil, power and ground circuits for that bank. Refer to «Engine Controls Schematics»(/chevrolet/cab-chassis-silverado-3500/2004-2007/remont/testing-diagnostics/#engine-controls-81l-introduction) .

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

1. 2: If the actual CKP variation values are not within the learned values, the misfire counters may increment.
2. 3: DTC P0135 or P0155 can be set because of a misfire.

DTC P0300

The Crankshaft Position (CKP) System variation learn feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, and the crankshaft position sensors. The calculated error allows the powertrain control module (PCM) to accurately compensate for reference period variations. This enhances the ability of the PCM to detect misfire events over a wider range of engine speed and load.

The CKP System variation compensating values are stored in PCM memory after a learn procedure has been performed. If the actual CKP variation is not within the CKP System variation compensating values stored in the PCM, DTC P0300 may set.

If the CKP System variation values are not stored in the PCM memory, DTC P0315 sets.

This diagnostic procedure supports the following DTC

DTC P0315 Crankshaft Position (CKP) System Variation Not Learned

1. DTCs P0335, P0336, P0341, P0342, P0343 are not set.
2. The engine coolant temperature (ECT) is more than 70°C (158°F).
3. This diagnostic runs continuously when the above conditions are met.

The CKP System variation values are not stored in the PCM memory.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0315

The knock sensors (KS) produce an AC signal when specific frequencies are detected. When the engine operates, the powertrain control module (PCM) learns a minimum and maximum frequency of noise of normal engine operation. The KS System monitors both KS in order to determine if knock is present. If the KS System determines that excessive knock is present, the PCM retards the spark timing based on the signals from the KS System. The PCM then retards timing until no knock is present.

This diagnostic procedure supports the following DTC

DTC P0325 Knock Sensor (KS) Circuit

1. The engine is running.
2. The engine run time more than 10 seconds.
3. The ignition 1 signal is more than 10 volts.
4. This diagnostic runs continuously when the above conditions are met.

A malfunction with the KS System or the circuits within the PCM are faulty for 15 seconds or more.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0325

The knock sensors (KS) produce an AC signal when specific frequencies are detected. When the engine operates, the powertrain control module (PCM) learns a minimum and maximum frequency of noise of normal engine operation. The KS System monitors both knock sensors in order to determine if knock is present. If the KS System determines that excessive knock is present, the PCM retards the spark timing based on the signals from the KS system. The PCM then retards the timing until no knock is present. When the PCM detects a frequency that is less than or more than a defined range, DTC P0327 will set for a failure in KS 1 which is located on bank 1 on the drivers side of the engine or DTC P0332 will set for a failure in KS 2 which is located on bank 2 on the passenger side of the engine.

DTC Descriptors

This diagnostic procedure supports the following DTCs

1. DTC P0327 Knock Sensor (KS) 1 Circuit Low Frequency
2. DTC P0332 Knock Sensor (KS) 2 Circuit Low Frequency

1. DTCs P0106, P0107, P0108, P0116, P0117, P0118, P0125, P1114, or P1115 are not set.
2. The engine speed is between 1,600-3,000 RPM.
3. The manifold absolute pressure (MAP) is less than 45 kPa.
4. The engine coolant temperature (ECT) is more than 60°C (140°F).
5. The engine run time is more than 20 seconds.
6. The ignition more than 10 volts.
7. This diagnostic runs continuously when the above conditions are met.

The PCM determines that this frequency is less than or more than the expected amount for 3 seconds or more.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

Inspect the KS for proper installation. A KS that is loose or over torqued may cause either DTC to set.

For an intermittent, refer to Testing for Intermittent Conditions and Poor Connections .

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

1. 2: This step verifies the malfunction is present.
2. 3: This test will isolate the KS from the rest of the circuit.
3. 4: Tapping on the engine block near the appropriate KS will simulate an engine knock.

DTC P0327 or P0332

The crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. The CKP sensor is connected directly to the powertrain control module (PCM), and consists of the following circuits

1. The 12-volt reference circuit
2. The low reference circuit
3. The CKP sensor signal circuit

If the PCM detects no signal from the CKP sensor for more than 3 seconds, DTC P0335 sets.

This diagnostic procedure supports the following DTC

DTC P0335 Crankshaft Position (CKP) Sensor Circuit

1. DTCs P0101, P0102, P0103, P0341, P0342, or P0343 are not set.
2. The camshaft position (CMP) sensor is transitioning.
3. The mass air flow (MAF) is more than 3 g/s in the crank mode.
4. The MAF is more than 5 g/s in the running mode.
5. This diagnostic runs continuously when the above conditions are met.

The PCM detects no signal from the CKP sensor for more than 3 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

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

1. 3: This step determines if the fault is present.
2. 6: This step simulates a CKP sensor signal to the PCM. If the PCM receives the signal, the fuel pump will operate for about two seconds.

DTC P0335

The crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. The CKP sensor is connected directly to the powertrain control module (PCM), and consists of the following circuits

1. The 12-volt reference circuit
2. The low reference circuit
3. The CKP sensor signal circuit

If the PCM detects that the CKP sensor signal is incorrect for more than 120 seconds, DTC P0336 sets.

This diagnostic procedure supports the following DTC

DTC P0336 Crankshaft Position (CKP) Sensor Circuit

1. The engine is cranking or running.
2. This diagnostic runs continuously when the above conditions are met.

The PCM determines that the CKP sensor signal is out of range for more than 120 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

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

1. 2: This step verifies that the malfunction is present.
2. 3: This step tests for electromagnetic interference (EMI) on the CKP sensor circuits.

DTC P0336

The camshaft position (CMP) sensor works in conjunction with a 1 X reluctor wheel on the camshaft. The powertrain control module (PCM) provides a 12-volt reference to the CMP sensor as well as a low reference and a signal circuit.

As the camshaft rotates, the reluctor wheel interrupts a magnetic field produced by a magnet within the sensor. The sensors internal circuitry detects this and produces a signal which the PCM reads.

The CMP sensor 1 X signal is used by the PCM to determine if the cylinder at top dead center (TDC) is on the firing stroke or the exhaust stroke. The PCM can determine TDC for all cylinders by using the crankshaft position (CKP) sensor 24 X signal alone. The engine will start without a CMP signal as long as the PCM receives the CKP sensor 24 X signal. A slightly longer cranking time may be a symptom of this condition. The system attempts synchronization and looks for an increase in engine speed indicating that the engine started. If the PCM does not detect an increase in engine speed, the PCM assumes that the PCM incorrectly synchronized to the exhaust stroke and re-syncs to the opposite cam position. If the PCM detects that a CMP to CKP mis-match has occurred DTC P0341 sets.

This diagnostic procedure supports the following DTC

DTC P0341 Camshaft Position (CMP) Sensor Performance

1. The engine is running and the engine speed is less than 4,000 RPM.
2. This diagnostic runs continuously when the above conditions are met.

The PCM detects that a CMP to CKP mismatch has occurred.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The following conditions may cause this DTC to set

1. Camshaft reluctor ring damage
2. The sensor coming in contact with the reluctor ring
3. Foreign material passing between the sensor and the reluctor ring
4. Excessive camshaft end-play
5. Wiring routed too close to secondary ignition components

If you suspect the condition is intermittent, refer to Testing for Intermittent Conditions and Poor Connections .

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

1. 3: This step inspects for electromagnetic interference (EMI) on the CMP sensor circuits.
2. 6: Damage to the face of the sensor could indicate foreign material passing between the CMP sensor and the reluctor wheel. This condition would cause this DTC to set. Damage to the reluctor wheel would affect the CMP sensor output.

DTC P0341

The camshaft position (CMP) sensor works in conjunction with a 1 X reluctor wheel on the camshaft. The powertrain control module (PCM) provides a 12-volt reference to the CMP sensor as well as a low reference and a signal circuit.

As the camshaft rotates, the reluctor wheel interrupts a magnetic field produced by a magnet within the sensor. The sensors internal circuitry detects this and produces a signal which the PCM reads.

The CMP sensor 1 X signal is used by the PCM to determine if the cylinder at top dead center (TDC) is on the firing stroke or the exhaust stroke. The PCM can determine TDC for all cylinders by using the crankshaft position (CKP) sensor 24 X signal alone. The engine will start without a CMP signal as long as the PCM receives the CKP sensor 24 X signal. A slightly longer cranking time may be a symptom of this condition. The system attempts synchronization and looks for an increase in engine speed indicating that the engine started. If the PCM does not detect an increase in engine speed, the PCM assumes that the PCM incorrectly synchronized to the exhaust stroke and re-syncs to the opposite cam position. If the PCM detects that a CMP signal is constantly low, DTC P0342 sets.

This diagnostic procedure supports the following DTC

DTC P0342 Camshaft Position (CMP) Sensor Circuit Low Voltage

1. The engine is running.
2. The engine speed is less than 4,000 RPM.
3. This diagnostic runs continuously when the above conditions are met.

The PCM detects that the CMP sensor signal is low for 1.5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The following conditions may cause this DTC to set

1. Camshaft reluctor ring damage
2. The sensor coming in contact with the reluctor ring
3. Foreign material passing between the sensor and the reluctor ring
4. Excessive camshaft end-play
5. Wiring routed too close to secondary ignition components

If the condition is intermittent, refer to Testing for Intermittent Conditions and Poor Connections .

The number below refers to the step number on the diagnostic table.

1. 5: This step tests the CMP sensor signal circuit. Applying a voltage causes the CMP Sensor High to Low and Low to High parameter to increase if the circuit and the PCM are operating properly.

DTC P0342

The camshaft position (CMP) sensor works in conjunction with a 1 X reluctor wheel on the camshaft. The powertrain control module (PCM) provides a 12-volt reference to the CMP sensor as well as a low reference and a signal circuit.

As the camshaft rotates, the reluctor wheel interrupts a magnetic field produced by a magnet within the sensor. The sensors internal circuitry detects this and produces a signal which the PCM reads.

The CMP sensor 1 X signal is used by the PCM to determine if the cylinder at top dead center (TDC) is on the firing stroke or the exhaust stroke. The PCM can determine TDC for all cylinders by using the crankshaft position (CKP) sensor 24 X signal alone. The engine will start without a CMP signal as long as the PCM receives the CKP sensor 24 X signal. A slightly longer cranking time may be a symptom of this condition. The system attempts synchronization and looks for an increase in engine speed indicating that the engine started. If the PCM does not detect an increase in engine speed, the PCM assumes that the PCM incorrectly synchronized to the exhaust stroke and re-syncs to the opposite cam position. If the PCM detects that the CMP signal is constantly high, DTC P0343 sets.

This diagnostic procedure supports the following DTC

DTC P0343 Camshaft Position (CMP) Sensor Circuit High Voltage

1. The engine is running.
2. The engine speed is less than 4,000 RPM.
3. This diagnostic runs continuously when the above conditions are met.

The PCM detects that the CMP sensor signal is high for 1.5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The following conditions may cause this DTC to set

1. Camshaft reluctor ring damage
2. The sensor coming in contact with the reluctor ring
3. Foreign material passing between the sensor and the reluctor ring
4. Excessive camshaft end-play
5. Wiring routed too close to secondary ignition components

If the condition is intermittent, refer to Testing for Intermittent Conditions and Poor Connections .

The number below refers to the step number on the diagnostic table.

1. 5: This step tests the CMP sensor signal circuit. Applying a voltage causes the CMP Sensor High to Low and Low to High parameter to increase if the circuit and the PCM are operating properly.

DTC P0343

The ignition system on this engine uses an individual ignition coil for each cylinder. The powertrain control module (PCM) controls the ignition system operation. The PCM controls each coil using one of eight ignition control (IC) circuits. The PCM commands the IC circuit low when a spark event is requested. This causes the IC module to energize the ignition coil to create a spark at the spark plug. Each ignition coil has the following circuits

1. An ignition 1 voltage circuit
2. A ground circuit
3. An IC circuit
4. A low reference circuit

Sequencing and timing are PCM controlled. If the PCM detects that the IC circuit is out of range, DTC P0351-P0358 sets.

This diagnostic procedure supports the following DTCs

1. DTC P0351 Ignition Coil 1 Control Circuit
2. DTC P0352 Ignition Coil 2 Control Circuit
3. DTC P0353 Ignition Coil 3 Control Circuit
4. DTC P0354 Ignition Coil 4 Control Circuit
5. DTC P0355 Ignition Coil 5 Control Circuit
6. DTC P0356 Ignition Coil 6 Control Circuit
7. DTC P0357 Ignition Coil 7 Control Circuit
8. DTC P0358 Ignition Coil 8 Control Circuit

1. The engine is operating.
2. This diagnostic runs continuously when the above conditions are met.

The PCM detects the IC circuit is grounded, open, or shorted to voltage for less than 1 second.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

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

1. 3: This step verifies the integrity of the IC circuit and the PCM output.
2. 4: This step tests for a short to ground on the IC circuit.

DTC P0351-P0358

The three-way catalytic converter (TWC) reduces emissions of hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx). The catalyst within the converter promotes a chemical reaction, which oxidizes the HC and CO that are present in the exhaust gas. This process converts these chemicals into water vapor and carbon dioxide (CO2), and will reduce the NOx, by converting them into nitrogen. The catalytic converter also stores oxygen. The powertrain control module (PCM) monitors this process using heated oxygen sensor (HO2S) bank 1 sensor 2 and HO2S bank 2 sensor 2, located in the exhaust stream after the TWC. These sensors are referred to as the catalyst monitor sensors. The catalyst monitor sensors produce an output signal the PCM uses to indicate the oxygen storage capacity of the catalyst. This determines the catalysts ability to effectively convert the exhaust emissions.

If the catalyst is functioning correctly, the HO2S bank 1 sensor 2 and HO2S bank 2 sensor 2 signals will be far less active than the signals that are produced by HO2S bank 1 sensor 1 and HO2S bank 2 sensor 1. This indicates that the TWC oxygen storage capacity is at an acceptable threshold. When the response time of the catalyst monitor sensors are close to that of the fuel control sensors, the ability of the catalyst to store oxygen may be below an acceptable threshold.

The PCM performs this diagnostic test at idle. When the conditions for running this DTC are met, the following occurs

1. The air-to-fuel ratio transitions from lean to rich.
2. The air-to-fuel ratio transitions from rich to lean, opposite the first air-to-fuel ratio transition.
3. The PCM captures the response time of the front and the rear HO2S when the air-to-fuel ratio transitions occur. The HO2S response time changes from less than 350 mV to more than 600 mV, and from more than 600 mV to less than 350 mV.
4. The PCM measures the time necessary for the rear HO2S voltage to cross a reference lean-to-rich threshold, and the time necessary for the front HO2S voltage to cross the same lean-to-rich threshold. The difference between the front HO2S time and the rear HO2S time indicates the oxygen storage capacity of the catalyst. If the PCM detects that this time difference is less than a predetermined value, DTC P0420 for bank 1 or DTC P0430 for bank 2 sets.

This diagnostic procedure supports the following DTCs

1. DTC P0420 Catalyst System Low Efficiency Bank 1
2. DTC P0430 Catalyst System Low Efficiency Bank 2

1. DTCs P0053, P0054, P0059, P0060, P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0120, P0128, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0151, P0152, P0153, P0154, P0155, P0157, P0158, P0160, P0161, P0171, P0172, P0174, P0175, P0200, P0220, P0300, P0325, P0327, P0332, P0335, P0336, P0341, P0342, P0343, P0351-P0358, P0442, P0443, P0446, P0449, P0452, P0453, P0455, P0496, P0500, P0502, P0503, P0506, P0507, P1125, P1133, P1134, P1153, P1154, P1516, P2101, P2108, P2120, P2121, P2125, P2135, P2A01, P2A04, U0107 are not set.
2. The engine has been running for more than 10 minutes.
3. The intake air temperature (IAT) is between -7 to +85°C (+20 and +185°F).
4. The barometric pressure (BARO) is more than 74 kPa.
5. The engine coolant temperature (ECT) is more than 70-120°C (158-248°F).
6. Since the end of the last idle period, the engine speed has been more than 850 RPM for 47 seconds.
7. The engine must be at a stable idle speed, within 200 RPM of desired idle.
8. The battery voltage is more than 11 volts.
9. The Closed Loop fuel control is enabled.
10. This diagnostic attempts one test during each valid idle period once the above conditions have been met. This diagnostic attempts up to 12 tests during each drive cycle.

1. The PCM determines that the oxygen storage capability of the TWC has degraded to less than a calibrated threshold.
2. This diagnostic may conclude in as few as one test attempt. However, this diagnostic may require as many as 18 test attempts, which would require at least 3 drive cycles. Each test attempt concludes within 1.5 minutes.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. The catalyst test may abort due to a change in the engine load. Do not change the engine load, ensure the AC is OFF, the coolant fan is not cycling, while a catalyst test is in progress.
2. Driving the vehicle under the conditions outlined in the Inspection/Maintenance (I/M) section can verify whether the fault is present.
3. These conditions may cause a catalytic converter to degrade. Inspect for the following conditions: An engine misfire High engine oil or high coolant consumption Retarded spark timing A weak or poor spark A lean fuel mixture A rich fuel mixture A damaged oxygen sensor or wiring harness If an intermittent condition cannot be duplicated, the information included in Freeze Frame data can be useful in determining the vehicle operating conditions when the DTC was set.
4. The catalyst may have been temporarily contaminated with a chemical from a fuel additive, fuel contamination or any of the above conditions.

If the condition is determined to be intermittent, refer to Intermittent Conditions .

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

1. 5: A catalytic converter which has been discolored may be due to an engine running rich, lean or had a previous misfire. Verifying the fuel trim percentages may be of assistance in determining if such a condition exists.
2. 6: This steps inspects for conditions than can cause the TWC efficiency to appear degraded.

DTC P0420 or P0430

This diagnostic tests the Evaporative Emission (EVAP) System for a small leak when the key is turned OFF and the correct conditions are met.

Heat is transferred into a vehicle fuel tank while the vehicle is operating. When the vehicle is turned OFF, a change in the fuel tank vapor temperature occurs, which results in corresponding pressure changes in the fuel tank vapor space. This change is monitored by the control module using the fuel tank pressure sensor input. The control module then makes a judgement on the integrity of the system. With a 0.51 mm (0.020 in) leak in the system, the amount of pressure change observed is significantly less than that of a sealed system.

If the control module detects a pressure change less than a calibrated amount, DTC P0442 sets.

This diagnostic procedure supports the following DTC

DTC P0442 Evaporative Emission (EVAP) System Small Leak Detected

1. DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0125, P0335, P0336, P0443, P0446, P0449, P0451, P0452, P0453, P0454, P0455, P0464, P0496, P0500, P0502, P1106, P1107, P2610 are not set.
2. The diagnostic runs once with a 10 hour minimum between tests after a fail.
3. The start up intake air temperature (IAT) is between 4-30°C (39-86°F).
4. The start up engine coolant temperature (ECT) is less than 30°C (86°F).
5. The start up IAT and ECT are within 8°C (15°F).
6. The barometric pressure (BARO) is greater than 74 kPa.
7. The ambient air temperature is between 2-32°C (36-90°F).
8. The engine run time minimum is 600 seconds.
9. The odometer displays greater than 10 miles.
10. The vehicle has traveled more than 3 miles this trip.
11. The ECT is more than 70°C (158°F).
12. The fuel level is between 15-85 percent.
13. The ignition is OFF.
14. One test occurs at ignition OFF after a cold start drive cycle and may require up to 45 minutes to complete. For the controller to report a fail, several tests must be completed with at least 17 hours between each test.

The control module detects a pressure change that is less than a calibrated amount.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. To help locate intermittent leaks, use the J 41413-200 Evaporative Emissions System Tester (EEST) to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the J 41413-SPT High Intensity White Light.
2. A condition may exist where a leak in the EVAP system only exists under a vacuum condition. This condition may be detected by using a scan tool PURGE/SEAL function to seal the EVAP system and create a vacuum. Then observe the FTP parameter for vacuum decay.
3. To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 41413-SPT .
4. For intermittent conditions, refer to «Testing for Intermittent Conditions and Poor Connections»(ref-197325-S02683201702005101100000) .

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

1. 3: Introducing smoke in 15-second intervals may allow smaller leak areas to be more noticeable. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.
2. 5: This step verifies that repairs are complete and that no other condition is present.

DTC P0442

An ignition voltage is supplied directly to the evaporative emission (EVAP) canister purge solenoid valve. The EVAP canister purge solenoid valve is pulse width modulated (PWM). The scan tool displays the amount of ON time as a percentage. The control module monitors the status of the driver. The control module controls the EVAP canister purge solenoid valve ON time by grounding the control circuit via an internal switch called a driver. If the control module detects an incorrect voltage for the commanded state of the driver, this DTC sets.

This diagnostic procedure supports the following DTC

DTC P0443 Evaporative Emission (EVAP) Purge Solenoid Control Circuit

1. The engine speed is more than 400 RPM.
2. The system voltage is between 10-18 volts.
3. DTC P0443 runs continuously once the above conditions are met.

1. The control module detects that the commanded state of the driver and the actual state of the control circuit do not match.
2. The above conditions are present for a minimum of 5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

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

1. 2: This step tests if the concern is active. The EVAP canister purge solenoid valve is PWM. You should hear a clicking sound when the EVAP canister purge solenoid valve is commanded to 50 percent. The clicking sound should stop when the EVAP canister purge solenoid valve is commanded to 0 percent. The rate at which the valve cycles should increase when the commanded state is increased, and decrease when the commanded state is decreased.
2. 5: This step verifies that the control module is providing ground to the EVAP canister purge solenoid valve.
3. 6: This step tests if a ground is constantly being applied to the EVAP canister purge solenoid valve.

DTC P0443

This DTC tests the Evaporative Emission (EVAP) System for a restricted or blocked EVAP vent path. The control module commands the EVAP canister purge solenoid valve Open and the EVAP canister vent solenoid valve Closed. This allows vacuum to be applied to the EVAP system. Once a calibrated vacuum level has been reached, the control module commands the EVAP canister purge solenoid valve Closed and the EVAP canister vent solenoid valve Open. The control module monitors the fuel tank pressure (FTP) sensor for a decrease in vacuum. If the vacuum does not decrease to near 0 inches H2O in a calibrated time, this DTC sets.

The following table illustrates the relationship between the ON and OFF states, and the Open or Closed states of the EVAP canister purge and vent solenoid valves.

DTC P0446

This diagnostic procedure supports the following DTC

DTC P0446 Evaporative Emission (EVAP) Vent System Performance

1. DTCs P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0135, P0136, P0137, P0138, P0140, P0141, P0151, P0152, P0153, P0154, P0155, P0156, P0157, P0158, P0160, P0161, P0220, P0442, P0443, P0449, P0451, P0452, P0453, P0454, P0455, P0464, P0502, P0503, P1111, P1112, P1114, P1115, P1121, P1122, P1125, P2135 are not set.
2. The ignition voltage is between 10-18 volts.
3. The barometric pressure (BARO) is greater than 75 kPa.
4. The fuel level is between 15-85 percent.
5. The engine coolant temperature (ECT) is between 4-30°C (39-86°F).
6. The intake air temperature (IAT) is between 4-30°C (39-86°F).
7. The start up ECT and IAT are within 9°C (16°F) of each other.
8. DTC P0446 runs once per cold start when the above conditions are met.

1. The fuel tank pressure sensor is less than -12 inches H2O.
2. The above condition is present for more than 5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. When using the electronic emission system tester (EEST) to apply pressure, you can regulate the amount of pressure by activating the remote switch ON and OFF while observing pressure in the EVAP system using a scan tool. DO NOT use more than 5 inches H2O. More than 5 inches H2O applied to the EVAP system can cause the canister vent solenoid valve to temporarily remain in the closed position, which could lead to misdiagnosis in this procedure.
2. An intermittent condition could be caused by a damaged EVAP vent housing, a temporary blockage at the EVAP canister vent solenoid valve inlet, or a pinched vent hose. A blockage in the vent system will also cause a poor fuel fill problem.
3. For intermittent conditions, refer to «Testing for Intermittent Conditions and Poor Connections»(ref-197325-S02683201702005101100000) .
4. An EVAP canister, vent hose or vent solenoid valve that has restricted flow may cause this DTC to set. Using purge solenoid valve command with a scan tool, will allow vacuum to be applied to the system instead of pressure. With the EVAP canister vent solenoid valve open and the EVAP canister purge solenoid valve commanded to 100 percent, vacuum should not increase to more than 9 inches H2O.

DTC P0446

A battery positive is supplied to the evaporative emission (EVAP) canister vent solenoid valve. The control module grounds the EVAP canister vent solenoid valve control circuit to close the valve by means of an internal switch called a driver. The scan tool displays the commanded state of the EVAP canister vent solenoid valve as ON or OFF. The control module monitors the status of the driver. If the control module detects an incorrect voltage for the commanded state of the driver, this DTC sets.

The following table illustrates the relationship between the ON and OFF states, and the OPEN or CLOSED states of the EVAP canister vent solenoid valve.

DTC P0449

This diagnostic procedure supports the following DTC

DTC P0449 Evaporative Emission (EVAP) vent Solenoid Control Circuit

1. The engine speed is more than 400 RPM.
2. The system voltage is between 10-18 volts.
3. DTC P0449 runs continuously once the above conditions are met.

1. The control module detects that the commanded state of the driver and the actual state of the control circuit do not match.
2. The above conditions are present for a minimum of 5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

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

1. 2: Listen for a click when the valve operates. Verify that both the ON and the OFF states are commanded.
2. 5: This step verifies that the control module is providing ground to the EVAP canister vent solenoid valve.
3. 6: This step tests if the EVAP canister vent solenoid valve control circuit is grounded.

DTC P0449

The fuel tank pressure (FTP) sensor measures air pressure or vacuum in the Evaporative Emission (EVAP) System. The control module supplies a 5-volt reference and a low reference circuit to the FTP sensor. The FTP sensor signal voltage varies, depending on EVAP System pressure or vacuum. The controller uses this FTP signal to determine atmospheric pressure for use in the engine-off small leak test, P0442. Before using this signal as an atmospheric reference, it must first be re-zeroed. If the FTP signal is out of range during the re-zero procedure, this DTC will set.

This diagnostic procedure supports the following DTC

DTC P0451 Fuel Tank Pressure (FTP) Sensor Performance

1. DTC P0451 runs only when the engine-off natural vacuum small leak test, DTC P0442, executes.
2. The number of times this test runs can range from 0-2 per engine-off period. The length of the test can be up to 40 minutes.

This DTC will set if the controller is unable to re-zero the FTP sensor voltage within a calibrated range during the engine-off small leak test, P0442.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the MIL after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and DTC with a scan tool.

1. When using the J 41413-200 Evaporative Emission System Tester (EEST) to apply pressure, you can regulate the amount of pressure by activating the remote switch ON and OFF while observing pressure in the EVAP system using a scan tool.
2. A restriction in the EVAP canister or vent lines could prevent fuel vapor pressure from bleeding off fast enough. If the vent system cannot bleed off pressure fast enough, this code can set. When pressure is applied to the system and released, a properly operating system will return to the atmospheric pressure rapidly. By using a scan tool and the J 41413-200 pressure can be applied to the system, then released, while monitoring the FTP Sensor parameter to see that pressure can be released within 30 seconds.
3. An FTP sensor that is skewed or does not have a linear transition from low to high may cause this code to set. A scan tool output controls, snapshot, and plot functions can help detect erratic sensor response. To test the sensor signal under vacuum conditions, use the Quick Snapshot and the Purge/Seal functions to capture data while commanding purge to 20 percent, then plot the data to look for erratic sensor operation. A similar test can be done for the pressure side of the sensor operation by applying pressure with the J 41413-200 while taking a snapshot.
4. A full fuel tank may cause misdiagnosis.

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

1. 4: This step tests for the signal voltage that represents atmospheric pressure. Removing the fuel fill cap ensures a vented EVAP System. Record the value for possible use later in the diagnostic table.
2. 5: This step tests the accuracy of the FTP sensor by comparing the electrical signal value to the EEST mechanical gage value.
3. 8: A restricted EVAP System will not allow the nitrogen to flow freely through the system. A restriction will cause the FTP Signal Voltage parameter to decrease as the pressure builds.

DTC P0451

The fuel tank pressure (FTP) sensor measures the difference between the air pressure or vacuum in the evaporative emission (EVAP) system, and the outside air pressure. The control module supplies a 5-volt reference and a low reference circuit to the FTP sensor. The FTP sensor signal circuit voltage varies depending on EVAP system pressure or vacuum. If the FTP sensor signal voltage goes below a calibrated value, this DTC sets.

The following table illustrates the relationship between the FTP sensor signal voltage and the EVAP system pressure/vacuum.

DTC P0452

This diagnostic procedure supports the following DTC

DTC P0452 Fuel Tank Pressure (FTP) Sensor Circuit Low Voltage

1. The engine is running.
2. DTC P0452 runs continuously once the above condition is met.

The engine is running.

1. The FTP sensor voltage is less than 0.1 volts.
2. All conditions are present for more than 5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

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

1. 5: This step tests for the proper operation of the circuit in the high voltage range.

DTC P0452

The fuel tank pressure (FTP) sensor measures the difference between the air pressure or vacuum in the evaporative emission (EVAP) system, and the outside air pressure. The control module supplies a 5-volt reference and a low reference circuit to the FTP sensor. The FTP sensor signal circuit voltage varies depending on EVAP system pressure or vacuum. If the FTP sensor signal voltage increases above a calibrated value, this DTC sets.

The following table illustrates the relationship between FTP sensor signal voltage and the EVAP system pressure/vacuum.

DTC P0453

This diagnostic procedure supports the following DTC

DTC P0453 Fuel Tank Pressure (FTP) Sensor Circuit High Voltage

1. The engine is running.
2. DTC P0453 runs continuously once the above condition is met.

1. The FTP sensor voltage is more than 4.9 volts.
2. All conditions are present for more than 5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The number below refers to the step number on the diagnostic table.

1. 2: If DTC P0641 or P0651 is set, the 5-volt reference circuit may be shorted to a voltage.

DTC P0453

The fuel tank pressure (FTP) sensor measures air pressure or vacuum in the Evaporative Emission (EVAP) System. The control module supplies a 5-volt reference and a low reference circuit to the FTP sensor. The FTP sensor signal voltage varies depending on EVAP System pressure or vacuum. The controller uses this FTP signal to determine atmospheric pressure for use in the engine OFF small leak test, P0442. This DTC will set if the control module detects an intermittent signal from the FTP that would prevent the engine-off small leak test, P0442, from running.

This diagnostic procedure supports the following DTC

DTC P0454 Fuel Tank Pressure (FTP) Sensor Circuit Intermittent

1. DTC P0454 runs only when the engine-off natural vacuum small leak test, P0442, executes.
2. This test can run once per engine-off period. The length of the test can be up to 40 minutes.

If, during the engine-off natural vacuum small leak test, P0442, the powertrain control module (PCM) detects an abrupt FTP signal change, other than a refueling event, this DTC will set.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the MIL after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and DTC with a scan tool.

Scan tool output controls, snapshot, and plot functions can help detect erratic sensor response. To look at the sensor signal under vacuum conditions, use snapshot and the purge/seal function to capture data while commanding purge to 20 percent, then plot the data to look for non-linear sensor operation. A similar inspection can be done for the pressure side of the sensor range by applying pressure with the J 41413-200 Evaporative Emissions System Tester (EEST) while taking a snapshot. DO NOT exceed 5 inches H2O when applying pressure.

The number below refers to the step number on the diagnostic table.

1. 3: Sealing the system will allow normal pressure in the EVAP System to preload the sensor. This will help put the sensor in a range that is more sensitive, making the test more accurate.

DTC P0454

The control module tests the evaporative emission (EVAP) system for a large leak. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister purge solenoid valve open and the EVAP canister vent solenoid valve closed. This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the control module commands the EVAP canister purge solenoid valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. If the system is unable to achieve the calibrated vacuum level, or the vacuum level decreases too rapidly, this DTC sets.

The following table illustrates the relationship between the ON and OFF states, and the OPEN or CLOSED states of the EVAP canister purge and vent solenoid valves.

DTC P0455

This diagnostic procedure supports the following DTC

DTC P0455 Evaporative Emission (EVAP) System Large Leak Detected

1. Before the powertrain control module (PCM) can report DTC P0455 failed, DTC P0496 must run and pass.
2. DTCs P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0135, P0136, P0137, P0138, P0140, P0141, P0151, P0152, P0153, P0154, P0155, P0156, P0157, P0158, P0160, P0161, P0220, P0442, P0443, P0449, P0451, P0452, P0453, P0454, P0464, P0496, P0502, P0503, P1111, P1112, P1114, P1115, P1125, P1122, P1121, P2135 are not set.
3. The engine is running.
4. The ignition voltage is between 10-18 volts.
5. The barometric pressure (BARO) is more than 75 kPa.
6. The fuel level is between 15-85 percent.
7. The engine coolant temperature (ECT) is between 4-65°C (39-149°F).
8. The intake air temperature (IAT) is between 4-75°C (39-167°F).
9. The start-up ECT and IAT are within 9°C (16°F) of each other.
10. DTC P0455 runs once per cold start.

The EVAP system is not able to achieve or maintain vacuum during the diagnostic test.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. To help locate intermittent leaks, use the J 41413-200 Evaporative Emissions System Tester (EEST) to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the J 41413-SPT High Intensity White Light. Introducing smoke in 15-second intervals will allow less pressure into the EVAP system. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.
2. A temporary blockage in the EVAP canister purge solenoid valve, purge pipe or EVAP canister could cause an intermittent condition. Inspect and repair any restriction in the EVAP system.
3. To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 41413-SPT .
4. Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.
5. For intermittent conditions, refer to «Testing for Intermittent Conditions and Poor Connections»(ref-197325-S02683201702005101100000) .

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

1. 4: Introducing smoke in 15-second intervals may allow smaller leak areas to be more noticeable. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.
2. 6: This step verifies proper operation of the FTP sensor.
3. 7: A normal operating FTP sensor should increase above 5 inches of H2O and stop between 6-7 inches of H2O.

DTC P0455

This DTC tests for undesired intake manifold vacuum flow to the Evaporative Emission (EVAP) System. The control module seals the EVAP system by commanding the EVAP canister purge solenoid valve Closed and the EVAP canister vent solenoid valve Closed. The control module monitors the fuel tank pressure (FTP) sensor to determine if a vacuum is being drawn on the EVAP system. If vacuum in the EVAP system is more than a predetermined value within a predetermined time, this DTC sets.

The following table illustrates the relationship between the ON and OFF states, and the Open or Closed states of the EVAP canister purge and vent solenoid valves.

DTC P0496

This diagnostic procedure supports the following DTC

DTC P0496 Evaporative Emission (EVAP) System Flow During Non-Purge

1. DTC P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0135, P0136, P0137, P0138, P0140, P0141, P0151, P0152, P0153, P0154, P0155, P0156, P0157, P0158, P0160, P0161, P0220, P0442, P0443, P0449, P0452, P0453, P0455, P0502, P0503, P1111, P1112, P1114, P1115, P1121, P1122, P1125, P2135 are not set.
2. The ignition voltage is between 10-18 volts.
3. The barometric pressure (BARO) is greater than 75 kPa.
4. The fuel level is between 15-85 percent.
5. The engine coolant temperature (ECT) is between 4-30°C (39-86°F).
6. The intake air temperature (IAT) is between 4-30°C (39-86°F).
7. The start up ECT and IAT are within 8°C (14°F) of each other.
8. DTC P0496 runs continuously when these conditions are met.

1. A continuous open purge flow condition is detected during the diagnostic test.
2. The fuel tank pressure decreases to less than a calibrated value.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0496

The throttle actuator control (TAC) system uses vehicle electronics and components to calculate and control the position of the throttle plate. In order to decrease idle speed the TAC system closes the throttle plate reducing airflow into the engine. In order to increase idle speed the TAC system opens the throttle plate allowing more airflow into the engine. If the actual idle RPM does not match the desired idle RPM within a calibrated time, this DTC sets.

This diagnostic procedure supports the following DTCs

1. DTC P0506 Idle Speed Low
2. DTC P0507 Idle Speed High

1. DTCs P0068, P0107, P0108, P0112, P0113, P0117, P0118, P0120, P0171, P0172, P0200, P0220, P0300, P0336, P0401, P0404, P0405, P0442, P0446, P0452, P0453, P0641, P0651, P1516, P2101, P2135 are not set.
2. The engine is operating for at least 2 seconds.
3. The engine coolant temperature (ECT) is more than -40°C (-40°F).
4. The intake air temperature (IAT) is more than -40°C (-40°F).
5. The barometric pressure (BARO) is more than 65 kPa.
6. The system voltage is between 9-18 volts.
7. The vehicle speed is less than 4.8 km/h (3 mph).
8. This diagnostic runs continuously when the above conditions are met.

1. The actual idle speed is approximately 150 RPM lower than or 100 RPM more than the desired idle speed.
2. The above condition is present for 15 seconds.

1. The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

If the condition is intermittent, refer to Testing for Intermittent Conditions and Poor Connections .

The number below refers to the step number on the diagnostic table.

1. 2: This test determines whether the engine can achieve the commanded RPM. If the engine does not reach the commanded RPM, the test determines whether the RPM is too high or too low.

DTC P0506 or P0507

See also:
• Fuel Injector Coil Test
• Engine Controls Schematics
• Powertrain Control Module (PCM) Connector End Views
• Engine Controls Connector End Views
• Special Tools
• Symptoms - Hydraulic Brakes
• Symptoms - Engine Mechanical
• CKP System Variation Learn Procedure
• DTC P0131 or P0151
• Crankcase Ventilation System Inspection/Diagnosis
• Alcohol/Contaminants-in-Fuel Diagnosis (Without Special Tool)
• Spark Plug Wire Inspection
• Spark Plug Inspection
• Crankshaft and Bearings Cleaning and Inspection
• Powertrain Control Module (PCM) Replacement
• Crankshaft and Bearings Installation
• Intermittent Conditions
• Evaporative Emission (EVAP) Canister Vent Solenoid Valve Replacement (Pickup)
• DTC P0420 or P0430