Home ReviewsRefund
Home/Chevrolet/Impala/Chevrolet Impala IX (2006-2016)/Repair manual/Testing & Diagnostics/Engine Controls and Fuel - 3.9l - DTC p0341 Through DTC p25…
Contents Wiring diagrams Section: Testing & Diagnostics All sections

Engine Controls and Fuel - 3.9l - DTC p0341 Through DTC p2544 Chevrolet Impala IX

Testing & Diagnostics ~14887 words

Diagnostic Instructions

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Diagnostic Fault Information

CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
5 V Reference CircuitP0641, P0452, P0107, P0532, P0522P0340P0641
Camshaft Position Sensor Signal CircuitP0340P0340P0340P0341
Low Reference CircuitP0340P0340

Typical Scan Tool Data

CircuitShort to GroundOpenShort to Voltage
Operating Conditions: Engine Running Parameter Normal Range: 400-6400 RPM. Camshaft Position Sensor parameter should match engine speed parameter.
5 V Reference Circuit0 RPM0 RPM0 RPM
Crankshaft Position Sensor Signal Circuit0 RPM0 RPM0 RPM
Low Reference CircuitSame as Engine Speed0 RPM0 RPM

Camshaft Position Sensor

Circuit/System Description

The 4X camshaft position sensor circuits consist of an engine control module (ECM) supplied 5 V reference circuit, low reference circuit, and an output signal circuit. The camshaft position sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor detects magnetic flux changes of the teeth and slots of a 4-tooth reluctor wheel attached to the camshaft. As each reluctor wheel tooth rotates past the camshaft position sensor, the resulting change in the magnetic field is used by the sensor electronics to produce a digital output pulse. The sensor returns a digital ON/OFF DC voltage pulse of varying frequency, with 4 varying width output pulses per camshaft revolution that represent an image of the camshaft reluctor wheel. The frequency of the camshaft position sensor output depends on the velocity of the camshaft. The ECM decodes the narrow and wide tooth pattern to identify camshaft position. This information is then used to determine the optimum ignition and injection points of the engine. The ECM also uses camshaft position sensor output information to determine the camshaft relative position to the crankshaft, to control camshaft phasing, and for limp-home operation.

Conditions for Running the DTC

  1. DTC P0335, P0336, P0641 or P0651 is not set.
  2. The engine is cranking or running.
  3. The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

IMPORTANTThe ECM detects engine movement by sensing the airflow through the mass air flow (MAF) sensor is more than 3 g/s, or by sensing crankshaft position sensor pulses.
  1. The ECM detects that the engine has started, but has received either of the following during the first engine revolution: Less than or more than 4 camshaft position sensor pulses, if equipped with an automatic transmission Less than 4 or more than 8 camshaft position sensor pulses, if equipped with a manual transmission OR
  2. The ECM detects that the engine is running, but receives less than 398 camshaft position or more than 402 camshaft position sensor pulses per 100 engine cycles in 800 of 1,000 engine cycles.

Action Taken When the DTC Sets

  1. DTC P0341 is a Type B DTC.
  2. The camshaft position actuator is commanded to the home or parked position.
  3. The ignition system defaults to a failed camshaft position sensor limp home mode.

Conditions for Clearing the MIL/DTC

DTC P0341 is a Type B DTC.

Diagnostic Aids

With a DTC set, the engine may crank for an extended period of time at start-up.

Reference Information

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. With the ignition OFF, inspect the engine wiring harnesses carrying the camshaft position sensor circuits for the following conditions: Close routing of secondary ignition wires Close routing of aftermarket electrical equipment Close to solenoids, motors, and relays Correct any wire harness routing or component placement conditions, if it is determined to be a possible source of electrical interference.
  2. Start the engine. Using the Live Plot function on the scan tool, select the camshaft position parameter. Change the minimum spec to 400 RPM and the maximum spec to 4,000 RPM. Select the crankshaft position sensor parameter. Change the minimum spec to 600 RPM and the maximum spec to 3,300 RPM.
  3. Observe the scan tool.
  4. Quickly accelerate and release the accelerator pedal several times. Do not exceed 3,200 RPM. The graphed lines on the Live Plot display should track together across the screen. If the vehicle passes the Circuit/System Verification test, operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

Circuit/System Testing

  1. Ignition OFF, inspect the camshaft position sensor for looseness and correct installation. If the sensor is loose, inspect the sensor and the O-ring for damage, replace as necessary.
  2. Inspect the engine for the following conditions: Engine oil for debris Camshaft reluctor wheel for damage Camshaft end play for excess movement-Refer to «Engine Mechanical Specifications»(/chevrolet/impala/ix-2006-2016/remont/mechanical/#engine-mechanical-39l-specifications__engine-mechanical-specifications) . The timing chain, tensioner, and sprockets for wear or damage If debris is found in the engine oil, inspect the internal engine components to determine the cause. Repair or replace any worn or damaged components. Refer to «Camshaft Timing Chain and Sprocket Cleaning and Inspection»(/chevrolet/impala/ix-2006-2016/remont/mechanical/#engine-mechanical-35l-repair-instructions-off-vehicle-1-of-3__camshaft-timing-chain-and-sprocket-cleaning) , and «Camshaft and Bearings Cleaning and Inspection»(/chevrolet/impala/ix-2006-2016/remont/mechanical/#engine-mechanical-35l-repair-instructions-off-vehicle-1-of-3) .

Component Testing

IMPORTANTYou must perform the Circuit/System Testing before proceeding with Component Testing.
  1. Inspect the camshaft position sensor for looseness and correct installation. Remove the camshaft position sensor from the engine and inspect the sensor and the O-ring for damage. If the sensor is loose, incorrectly installed, or damaged. Repair or replace the camshaft position sensor.
  2. Connect the camshaft position sensor connector to the camshaft position sensor. Turn ON the ignition, with the engine OFF.
  3. Ignition ON and engine OFF. Observe the Camshaft Position Active Counter parameter on the scan tool; pass a steel object by the tip of the sensor repeatedly. The Camshaft Position Active Counter parameter should increment. If the parameter does not increment, replace the camshaft position sensor.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
  2. «Camshaft Position Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-35l-repair-instructions) for camshaft position sensor replacement
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Ignition Coil 1 Control CircuitP0300, P0351P0300, P0351P0300, P0351P0300, P0351
Ignition Coil 2 Control CircuitP0300, P0352P0300, P0352P0300, P0352P0300, P0352
Ignition Coil 3 Control CircuitP0300, P0353P0300, P0353P0300, P0353P0300, P0353

There are 3 dual-tower ignition coils integrated with the ignition control module (ICM). The ICM contains coil driver circuits that operate the 3 coils. The ICM wiring includes the following circuits

  1. An ignition 1 voltage circuit
  2. A ground circuit
  3. An ignition coil 1 control circuit
  4. An ignition coil 2 control circuit
  5. An ignition coil 3 control circuit
  6. A low reference circuit

The engine control module (ECM) controls each ignition coil by transmitting timing pulses to the ICM on each of the ignition coil control circuits to enable properly timed spark events. The ignition coil 1 controls spark for companion cylinders 1 and 4. The ignition coil 2 controls spark for companion cylinders 2 and 5. The ignition coil 3 controls spark for companion cylinders 3 and 6.

  1. The engine is cranking or running.
  2. The DTCs run continuously when the above condition is met.

The PCM detects a fault in an ignition coil control circuit for 90 out of 100 engine cycles.

DTCs P0351, P0352, and P0353 are Type B DTCs.

DTCs P0351, P0352, and P0353 are Type B DTCs.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. With the engine running, observe the Cylinder 1 through 6 IC Circuit Status parameters with the scan tool. All of the parameters should display OK.
  2. With the engine running, observe the Misfire Current counters using the scan tool. The counters should not be incrementing.
  1. With the engine running, observe the applicable Cylinder IC Circuit Status parameters with the scan tool. If a parameter displays short Gnd/Open, test for an open/high resistance or a short to ground in the affected IC circuit. All wire circuit resistance should measure less than 2 ohms. If a parameter displays short to B+, test for a short to voltage in the affected IC circuit.
  2. Connect jumper wires from the harness connector of the ICM to the corresponding terminals of the ICM.
  3. Using the jumper wires, exchange the affected IC control circuit with a known good IC control circuit. Also exchange the spark plug wires of the corresponding coils.
  4. Start the engine.
  5. Observe the Misfire Current counters with the scan tool. If the misfire transfers with the suspect IC control circuit, replace the ECM. If the misfire remains with the coil, replace the ICM.
  1. With positive polarity to the low reference terminal, measure for 9,000-11,000 ohms at 20-23°C (68-74°F) room temperature between each of the ignition coil control terminals and the low reference terminal of the ICM. If the resistance is not within the specified range, replace the ICM.
  2. Measure for 7,000-15,000 ohms at 20-23°C (68-74°F) room temperature between each pair of coil towers on the ICM. If the resistance is not within the specified range, replace the ICM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
  2. «Ignition Coil Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

A 3-way catalytic converter (TWC) controls 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 the CO that are present in the exhaust gas. This process converts the HC and the CO into water vapor and carbon dioxide (CO2), and reduces the NOx, converting the NOx into nitrogen. The catalytic converter also stores oxygen. The engine control module (ECM) monitors this process by using a heated oxygen sensor (HO2S) that is in the exhaust stream after the TWC. The HO2S 2 produces an output signal that the ECM uses to calculate the oxygen storage capacity of the catalyst. This indicates the ability of the catalyst to convert the exhaust emissions efficiently. The ECM monitors the efficiency of the catalyst by allowing the catalyst to heat, then wait for a stabilization period while the engine is idling. The ECM then adds and removes fuel while monitoring the HO2S 2. When the catalyst is functioning properly, the HO2S 2 response to the extra fuel is slow compared to the response of the HO2S 1, which is located before the TWC. When the HO2S 2 response is near that of the HO2S 1, the oxygen storage capability and efficiency of the catalyst may be degraded below an acceptable threshold.

  1. DTCs P0030, P0036, P0053, P0054, P0068, P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0171, P0172, P0201, P0202, P0203, P0204, P0205, P0206, P0220, P0222, P0223, P0300, P0325, P0326, P0327, P0328, P0330, P0332, P0333, P0335, P0336, P0340, P0341, P0442, P0443, P0446, P0449, P0455, P0496, P0506, P0507, P1133, P1258, P1516, P2101, P2119, P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2138, P2176, P2A00, P2270, or P2271 is not set.
  2. Before the ECM performs the idle test, the vehicle must be driven under the following conditions: The engine speed is greater than 1,000 RPM The engine run time is greater than 10 minutes Both conditions exist for greater than 1 minute
  3. The throttle is in the rest position.
  4. The intake air temperature (IAT) is between -20 to +85°C (-4 to +185°F).
  5. The ignition voltage is greater than 11 volts.
  6. The engine coolant temperature (ECT) is between 70-125°C (156-257°F).
  7. The barometric pressure (BARO) is greater than 70 kPa.
  8. The vehicle speed is less than 3 km/h (2 mph).
  9. The Fuel Trim Learn is enabled.
  10. The short term fuel trim (FT) is between -10 and +10 percent.
  11. The catalytic converter (TWC) calculated temperature is greater than 450°C (1,742°F).
  12. The engine is operating in Closed Loop.
  13. The transmission is not in P/N (automatic transmission only).

This diagnostic attempts one test during each valid idle period once the above conditions have been met. This diagnostic attempts up to 6 tests during each drive cycle.

The ECM determines that the efficiency of the catalyst has degraded below a calibrated threshold.

DTC P0420 is a Type A DTC.

Conditions for Clearing the DTC

DTC P0420 is a Type A DTC.

Note. A new converter with less than 161 kilometers (100 miles) on it may set DTC P0420 due to out-gassing of the internal matting. Operating the vehicle at highway speeds for approximately 1 hour may correct the condition.

Inspect for the following conditions, which may cause a catalytic converter to degrade

  1. An engine misfire
  2. High engine oil or high coolant consumption
  3. Retarded spark timing
  4. A weak or poor spark
  5. A lean fuel mixture
  6. A rich fuel mixture
  7. A damaged oxygen sensor or wiring harness

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. Engine idling, observe the DTC information with a scan tool. Verify there are no HO2S or misfire DTCs set. If any of the DTCs are set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) to diagnosis the applicable DTC, before proceeding with this diagnostic procedure.
  2. Verify the following conditions do not exist with the catalytic converter: Dents A severe discoloration caused by excessive temperatures Road damage An internal rattle caused by damaged catalyst substrate Restrictions If a condition is found, replace the catalytic converter.
  3. Verify the following conditions do not exist with the exhaust system: Leaks Physical damage Loose or missing hardware Properly torqued HO2S If a condition is found, repair the exhaust system.
  4. Verify the following conditions do not exist with the HO2S 2: A grounded wiring harness Damage If a condition is found, replace the HO2S 2.
  5. If no physical condition is detected and the HO2S 2 is as active as the HO2S 1 after operating the engine at 1,500 RPM for 1 minute and then returning to a stabilized idle, then replace the appropriate catalytic converter.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Exhaust Leakage»(/chevrolet/impala/ix-2006-2016/remont/exhaust/#engine-exhaust-system__exhaust-leakage)
  2. «Restricted Exhaust»(/chevrolet/impala/ix-2006-2016/remont/exhaust/#engine-exhaust-system)
  3. «Heated Oxygen Sensor Replacement - Sensor 2»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-35l-repair-instructions)
  4. «Catalytic Converter Replacement (LGD/LZE)»(/chevrolet/impala/ix-2006-2016/remont/exhaust/#engine-exhaust-system)
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

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 from the exhaust system is transferred into a vehicle fuel tank while the vehicle is operating. When the vehicle is turned OFF and the EVAP system is sealed, 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 engine control module (ECM) using the fuel tank pressure sensor input. The ECM then makes a judgment on the integrity of the system. With a 0.51 mm (0.02 in) leak in the system, the amount of pressure change observed is significantly less than that of a sealed system.

IMPORTANTThe following conditions must be met prior to ignition OFF.
  1. Before the ECM can report DTC P0442 failed, DTCs P0446, P0455, and P0496 must run and pass.
  2. DTCs P0112, P0113, P0116, P0117, P0118, P0120, P0125, P0128, P0443, P0446, P0449, P0452, P0453, P0463, P0503, P1106, P1107, P1111, P1112, P1114, P1115, P1516, P2101, P2108, P2120, P2125, P2129, P2138, P2610 are not set.
  3. The diagnostic runs once after a cold start drive cycle.
  4. The start-up intake air temperature (IAT) is between 4-30°C (39-86°F).
  5. The start-up engine coolant temperature (ECT) is less than 30°C (86°F).
  6. The start-up IAT and ECT are within 8°C (15°F).
  7. The barometric pressure (BARO) is more than 74 kPa.
  8. The ambient air temperature is between 2-32°C (36-90°F).
  9. The engine run time minimum is 10 minutes.
  10. The vehicle has traveled more than 5 kilometers (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. A refueling event is not detected.
  15. DTC P0442 runs once per drive cycle when the above conditions are met.
  16. One test occurs at ignition OFF after a drive cycle, and may require up to 45 minutes to complete. No more than 2 tests per day are allowed.
  1. The ECM detects a pressure change that is less than a calibrated amount.
  2. The ECM must complete several engine OFF natural vacuum (EONV) tests before the diagnostic can turn the malfunction indicator lamp (MIL) ON or OFF.

DTC P0442 is a Type A DTC.

DTC P0442 is a Type A DTC.

  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. To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 41413-SPT .
  3. A condition may exist where a leak in the EVAP system only exists under a vacuum condition. By using the scan tool Purge/Seal function to create a vacuum, seal the system and observe the FTP parameter for vacuum decay, this type of leak may be detected.

DTC Type Reference

Description and Operation

Scan Tool Reference

Control Module References for scan tool information

Special Tools

  1. CH-48096 EVAP Service Access Port Tool
  2. GE-41415-50 Fuel Tank Cap Adapter
  3. J 41413-200 Evaporative Emission System Tester (EEST)
  4. J 41413-300 EVAP Cap and Plug Kit
  5. J 41413-SPT High Intensity White Light
  6. J 41413-VLV EVAP Port Vent Fitting Tool
  1. Disconnect the purge tube at the quick connector on the evaporative emission canister side of the Q12 evaporative emission canister purge solenoid valve and install the CH 48096: Port Tool.
  2. Using a scan tool, close the EVAP canister vent valve to seal the EVAP system.
  3. Use the flow meter on the J 41413-200 , calibrated to 0.51 mm (0.020 in) to determine that there is no leak in the EVAP system. If a leak is detected, use the J 41413-200 to apply smoke to the EVAP system at the service port or the purge tube until the leak is located using the J 41413-SPT .

Repair Verification

The malfunction indicator lamp (MIL) may remain ON after the repair unless the DTCs are cleared.

  1. Seal the EVAP system and use the flow meter on the J 41413-200 calibrated to 0.51 mm (0.020 in) to determine that there is no leak in the EVAP system.
  2. Clear the DTCs.
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundHigh ResistanceOpenShort to VoltageSignal Performance
Ignition 1 Voltage - Purge SupplyP0030, P0050, P0102, P0443P0443P0443
Battery Positive - Vent SupplyP0449P0449P0449
EVAP Purge Solenoid ControlP0443P0443P0443P0443
EVAP Vent Solenoid ControlP0449P0449P0449P0449

P0443

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.

P0449

Battery voltage is supplied to the 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.

  1. The ignition is ON.
  2. The system voltage is between 6-18 volts.
  3. DTC P0443 and P0449 run continuously when the above conditions are met.

The control module detects that the commanded state of the driver and the actual state of the control circuit do not match, for a minimum of 12 seconds.

  1. DTC P0443 is a Type B DTC.
  2. DTC P0449 is a Type B DTC.
  1. DTC P0443 is a Type B DTC.
  2. DTC P0449 is a Type B DTC.

Schematic Reference

Connector End View Reference

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  3. «Troubleshooting with a Test Lamp»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

With the ignition ON, and the engine OFF, you should hear a clicking sound when the EVAP canister purge solenoid valve is commanded to 50 percent with a scan tool. 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.

  1. With the ignition ON and the engine OFF, command the EVAP vent solenoid ON and OFF with a scan tool.
  2. Listen for a click when the valve operates. Verify that both the ON, and the OFF states are commanded.
  1. Ignition OFF, disconnect the harness connector at the EVAP canister purge solenoid valve.
  2. Ignition ON, verify that a test lamp illuminates between the voltage supply circuit terminal A and ground. If the test lamp does not illuminate, test the voltage supply circuit for a short tog round or an open/high resistance. If the circuit tests normal and the voltage supply circuit fuse is open, test or replace the EVAP canister purge solenoid.
  3. Connect a test lamp between the voltage supply circuit terminal A and the control circuit terminal B.
  4. Command the solenoid to 50 percent with a scan tool The test lamp should flash or illuminate when commanded to 50 percent, and turn OFF when commanded to 0 percent. If the test lamp does is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the control module. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the control module.
  5. If all circuits test normal, replace the EVAP canister purge solenoid valve.
  1. Ignition OFF, disconnect the harness connector at the EVAP canister vent solenoid valve.
  2. Ignition ON, verify that a test lamp illuminates between the voltage supply circuit terminal A and ground. If a test lamp does not illuminate, test the voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the voltage supply circuit fuse is open, test or replace the EVAP canister vent solenoid valve.
  3. Connect a test lamp between the voltage supply circuit terminal A and the control circuit terminal B.
  4. Command the solenoid ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between commanded states. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the control module. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the control module.
  5. If all circuits test normal, replace the EVAP canister vent solenoid valve.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Evaporative Emission Canister Purge Solenoid Valve Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  2. «Evaporative Emission Canister Vent Solenoid Valve Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-35l-repair-instructions)
  3. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for engine control module (ECM) replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

This DTC tests the evaporative emission (EVAP) system for a restricted or blocked EVAP vent path that would cause excess amounts of vacuum to be developed in the EVAP system. With the purge valve open and the canister vent valve open, if the EVAP system vacuum goes above a calibrated threshold, the test will fail.

Fuel Tank Pressure Sensor Signal VoltageFuel Tank Pressure
Less than 1.5 VPositive Pressure
More than 1.5 VNegative Pressure/Vacuum
  1. DTCs P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0125, P0128, P0502, P1106, P1107, P1111, P1112, P1114, P1115, P1125, P1516, P2101, P2108, P2119, P2120, P2125, P2138 are not set.
  2. The ignition voltage is between 10-18 volts.
  3. The barometric pressure (BARO) is more than 75 kPa.
  4. The fuel level is between 15-85 percent.
  5. DTC P0446 runs once per trip when the above conditions have been met.

The FTP sensor is more than -12 inches H2O vacuum for 5 seconds during the 13 minute test.

OR

The FTP is less than -2.5 inches H2O or more than +5 inches H2O for 60 seconds after a cold start ignition ON.

DTC P0446 is a Type B DTC.

DTC P0446 is a Type B DTC.

  1. 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 may also cause a poor fuel fill problem.
  2. An EVAP canister filter that is restricted can cause this DTC to set. Refer to «Evaporative Emission Canister Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions) .
  3. Disconnecting one component at a time while the EVAP system is under flow will help to pinpoint a restriction in the system.

Schematic Reference

Connector End View Reference

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  3. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Description and Operation

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 41413-200: Evaporative Emissions System Tester (EEST)

  1. Ignition ON and fuel cap removed, verify that the Fuel Tank Pressure Sensor parameter is between 1.3-1.7 volts. If not within the specified range, go to the fuel tank pressure sensor information in Circuit/System Testing.
  2. Install the fuel cap.
  3. With the engine running, the EVAP canister vent solenoid valve open, use a scan tool to command the EVAP canister purge solenoid valve to 100 percent. The fuel tank vacuum should not increase to more than -15 mmHg (-8 inches H2O). If the fuel tank vacuum is greater than the specified range, go to the restriction information in Circuit/System Testing.
  4. Using the scan tool, decrease the canister purge duty cycle from 100 percent to 0 percent. The vacuum should decrease to near zero. If the fuel tank vacuum does not return to zero or appears to decrease too slowly go to the restriction section in Circuit/System Testing.
  5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Note. Perform the Circuit/System Verification before proceeding with the Circuit/System Testing.

Restriction

  1. With the engine running, the EVAP canister vent solenoid valve open, and the EVAP canister purge solenoid valve commanded to 100 percent, the fuel tank vacuum should not increase to more than -15 mmHg (-8 inches H2O). If the fuel tank vacuum is greater than the specified value, isolate the restriction by disconnecting one component at a time while the EVAP canister purge solenoid valve is commanded to 100 percent and the vent valve is open.
  2. Using the scan tool, decrease the canister purge duty cycle from 100 percent to 0 percent. The vacuum should decrease to near zero. If the fuel tank vacuum does not return to zero, or appears to decrease too slowly, inspect the components in the EVAP vent system for a restriction.

Fuel Tank Pressure Sensor

  1. Ignition OFF, disconnect the harness connector at the fuel tank pressure sensor.
  2. Ignition OFF, test for less than 5 ohms between the low reference circuit terminal and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the fuel tank pressure sensor.
  1. «Fuel Tank Pressure Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  2. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming

With the engine running, the EVAP canister vent solenoid valve open and the EVAP canister purge solenoid valve commanded to 100 percent, the fuel tank vacuum should not increase to more than -15 mmHg (-8 inches H2O).

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundHigh ResistanceOpenShort to VoltageSignal Performance
FTP Sensor Low ReferenceP0446, P0451P0446P0451
FTP Sensor SignalP0452P0452P0453P0451, P0454
FTP Sensor 5-Volt ReferenceP0452, P0530, P0641P0451P0446, P0453P0453, P0530, P0641
CircuitNormal RangeShort to GroundOpenShort to Voltage
Operating Conditions: With EVAP system vented to atmosphere
FTP Sensor Low Reference0 V0 V
FTP Sensor Signal0 V0 V0-1.5 V5 V
FTP Sensor 5-Volt Reference0 V0-1.5 V5 V

FTP Sensor Voltage

The fuel tank pressure (FTP) sensor measures air pressure or vacuum in the evaporative emission (EVAP) system. The engine control module (ECM) supplies a 5-volt reference circuit and a low reference circuit to the FTP sensor. The FTP sensor signal voltage varies depending on EVAP system pressure or vacuum. The ECM also uses this FTP signal to determine atmospheric pressure for use in the engine-off small leak test, DTC P0442. Before using this signal as an atmospheric reference, it must first be re-zeroed.

P0451

  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 10 minutes.

P0452 and P0453

DTCs P0452 and P0453 run continuously when the ignition is ON.

P0454

  1. DTC P0454 runs only when the engine-off natural vacuum small leak test, DTC P0442, executes.
  2. This test can run once per engine-off period. The length of the test can be up to 10 minutes.
  3. A refueling event is not detected.

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, DTC P0442.

P0452

The FTP sensor voltage is less than 0.1 volt for more than 5 seconds.

P0453

The FTP sensor voltage is more than 4.9 volts for more than 5 seconds.

If, during the engine-off natural vacuum small leak test, DTC P0442, the ECM detects an abrupt FTP signal change, other than a refueling event, this DTC will set. An abrupt change is defined as a change of 1 inch H2O in the span of 1 second.

P0451 and P0454

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

P0452 and P0453

  1. The ECM illuminates the MIL on the second consecutive ignition cycle that the diagnostic runs and fails.
  2. The ECM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the ECM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the ECM records the operating conditions at the time of the failure. The ECM 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.

P0451

  1. 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, the re-zero procedure may not complete successfully, which could cause this code to set. By using the Purge Solenoid command on a scan tool, vacuum can 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, the vacuum should not increase to more than 9 inches H2O.
  2. Ensure that the reference port on the FTP sensor is unobstructed.

P0454

  1. This diagnostic is designed to detect an unexpected abrupt voltage signal change from the FTP.
  2. 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 30 percent, then plot the data to look for erratic sensor operation. A similar inspection can be done for the pressure side of the sensor range by applying pressure with the J 41413-200 while taking a snapshot.
  3. Ensure that the reference port on the FTP sensor is unobstructed.

Schematic Reference

Connector End View Reference

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 41413-200 Evaporative Emission System Tester (EEST)

  1. Remove the fuel cap.
  2. Turn ON the ignition, with the engine OFF.
  3. Observe the Fuel Tank Pressure Sensor parameter with a scan tool.
  4. The FTP Sensor parameter should be 1.5 volts.
  1. Ignition OFF, disconnect the harness connector at the FTP sensor.
  2. Ignition OFF, ensure that the ECM completely powers down and test for less than 5 ohms between the low reference circuit terminal A and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the control module.
  3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground. If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the control module. If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the control module.
  4. Verify the scan tool FTP sensor parameter is less than 0.2 volt. If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the control module.
  5. Install a 3A fused jumper wire at the signal circuit terminal B and the 5-volt reference circuit terminal C. Verify the scan tool FTP sensor voltage parameter is greater than 4.7 volts. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the control module.
  6. If all circuits test normal, replace the FTP sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Fuel Tank Pressure Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  2. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The ECM tests the Evaporative Emission (EVAP) System for a large leak or restrictions to the purge path in the EVAP system. When the enabling criteria has been met the ECM commands the evaporative emission canister vent solenoid valve ON and the evaporative emission canister purge solenoid valve ON, allowing vacuum into the evaporative emission system. The ECM monitors the fuel tank pressure sensor voltage to verify that the system is able to reach a predetermined level of vacuum within a set amount of time.

  1. Before the ECM can report DTC P0455 failed, DTC P0496 must run and pass.
  2. DTCs P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0125, P0442, P0443, P0446, P0449, P0452, P0453, P1111, P1112, P1114, P1115, P1125, P1135, P1351, P1352, P1361, P1362, P1516, P1548, P2101, P2107, P2108, P2119, P2120, P2125, P2135, P2138 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 start-up engine coolant temperature (ECT) is between 4-30°C (39-86°F).
  8. The start-up intake air temperature (IAT) is between 4-30°C (39-86°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 within 10 minutes of start-up.

The EVAP system is not able to achieve or maintain vacuum for up to 4 times during the diagnostic test.

DTC P0455 is a Type B DTC.

DTC P0455 is a Type B DTC.

  1. Inspect for a loose, missing, damaged, or incorrect fuel fill cap.
  2. Inspect for a damaged fuel filler neck seal surface.
  3. A blockage or restriction in the evaporative emission purge solenoid valve, purge pipe, evaporative emission canister, or vapor pipe, can cause this DTC to set.
  4. The evaporative emission system can be filled with smoke more quickly and completely by opening the system opposite the end where the smoke is injected. Close the system once smoke is observed.
  5. To help locate intermittent leaks using the J 41413-200: EEST, move all evaporative emission components while observing smoke with the J 41413-SPT: White Light.
  6. Individual components can be isolated and tested using adapters in the J 41413-300: Kit.
  7. A condition may exist where a leak in the evaporative emission system only exists under a vacuum condition. This type of leak may be detected by using the scan tool Purge/Seal function to create a vacuum in the evaporative emission system and then observe the fuel tank pressure parameter for vacuum decay.

Schematic Reference

Connector End View Reference

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  3. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

Description and Operation

Special Tools

  1. CH-48096 EVAP Service Access Port Tool
  2. GE-41415-50 Fuel Tank Cap Adapter
  3. J 41413-200 (J 41413-100) Evaporative Emission System Tester (EEST)
  4. J 41413-300 EVAP Cap and Plug Kit
  5. J 41413-311 EVAP Plug
  6. J 41413-VLV EVAP Service Port Vent Fitting
  7. J 41413-SPT High Intensity White Light

Note. Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize. Refer to the J 41413-200: EEST operation manual for detailed instructions in Evaporative Emission System Diagnosis .

  1. Connect the J 41413-200 to the vehicle EVAP service port. For vehicles without a service port, disconnect the purge tube at the quick connector on the EVAP canister side of the purge solenoid valve and install the CH-48096 .
  2. Seal the EVAP system and use the flow meter on the J 41413-200 , calibrated to 0.51 mm (0.02 in) to determine that there is no leak in the EVAP system. If a leak is detected, use the J 41413-200 to apply smoke to the EVAP system at the service port until the leak is located.
  3. To test for a restriction, connect the J 41413-200 nitrogen/smoke hose to the J 41413-311 brass cone adapter. Disconnect the hose at the fuel cap end of the GE-41415-50 . Connect the J 41413-311 to the disconnected hose on the GE-41415-50 . Install the GE-41415-50 filler neck end only to the vehicle.
  4. Allow the engine to idle.
  5. Use the Purge/Seal function to seal the system with a scan tool.
  6. Command the EVAP canister purge solenoid valve to 30 percent.
  7. The vacuum/pressure gauge on the J 41413-200 and the FTP parameter on the scan tool should both show vacuum. If the vacuum/pressure gauge shows vacuum but the FTP parameter does not show vacuum, replace the FTP sensor. If neither the Fuel Tank Pressure Sensor parameter nor the vacuum/pressure gauge shows vacuum, repair the restriction in the purge path.
  8. Verify that the vacuum increases to the abort limit on the scan tool or more than 3.2 volts, and the value is closely similar between the scan tool and the vacuum/pressure gauge on the J 41413-200 . If the values are not similar or the voltage did not reach 3.2 volts, replace the FTP sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Fuel Tank Pressure Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  2. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

This DTC tests for undesired intake manifold vacuum flow to the evaporative emission (EVAP) system. The engine control module (ECM) seals the EVAP system by commanding the EVAP canister purge solenoid valve OFF and the EVAP canister vent solenoid valve ON. The ECM 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.

Control Module CommandEVAP Canister Purge Solenoid ValveEVAP Canister Vent Solenoid Valve
ONOpenClosed
OFFClosedOpen
  1. DTCs P0107, P0108, P0112, P0113, P0117, P0118, P0125, P0128, P0442, P0443, P0446, P0449, P0452, P0453, P0445, P1106, P1107, P1111, P1112, P1114, P1115, P1516 are not set.
  2. The ignition voltage is between 10-18 volts.
  3. The barometric pressure (BARO) is more than 74 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. DTC P0496 runs once per cold start for 96 seconds.

The ECM detects vacuum during a non-purge condition.

  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.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  3. «Troubleshooting with a Test Lamp»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Start the engine.
  2. Seal the EVAP system using the Purge/Seal function with a scan tool.
  3. Observe the FTP sensor with a scan tool. The Fuel Tank Pressure Sensor parameter should be less than 1.7 volts.

Note. Perform the Circuit/System Verification before proceeding with the Circuit/System Testing.

Disconnect the EVAP purge pipe from the EVAP canister purge solenoid valve.

  1. If the Fuel Tank Pressure Sensor parameter is less than 1.7 volts, replace the EVAP canister purge solenoid valve.
  2. If the pressure is greater than 1.7 volts, replace the FTP sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Evaporative Emission Canister Purge Solenoid Valve Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  2. «Fuel Tank Pressure Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The throttle actuator control (TAC) motor is controlled by the engine control module (ECM). The DC motor located in the throttle body drives the throttle blade. In order to decrease idle speed, along with spark and fuel delivery changes the ECM commands the throttle closed reducing air flow into the engine and the idle speed decreases. In order to increase idle speed, the ECM commands the throttle plate open allowing more air to pass the throttle plate.

  1. DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0116, P0117, P0118, P0120, P0122, P0123, P0128, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0220, P0222, P0223, P0300, P0351, P0352, P0353, P0496, P0601, P0604, P0606, P060D, P0641, P0651, P1516, P2101, P2119, P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2138, or P2176 is not set.
  2. The engine has been running for greater than 60 seconds.
  3. The engine is idling for greater than 10 seconds.
  4. The AC mode state has not changed.
  5. The power steering load state has not changed.
  6. The transmission gear selector state has not changed.
  7. The engine coolant temperature (ECT) is greater than -40°C (-40°F).
  8. The intake air temperature (IAT) is greater than -40°C (-40°F).
  9. The barometric pressure (BARO) is greater than 72 kPa.
  10. The system voltage is between 9-18 volts.
  11. The vehicle speed is less than 4.8 km/h (3 mph).
  12. The DTCs run continuously when the above conditions are met.

P0506

The ECM detects that the actual idle speed is approximately 100 RPM lower than the desired idle speed.

P0507

The ECM detects that the actual idle speed is approximately 200 RPM higher than the desired idle speed.

DTCs P0506 and P0507 are Type B DTCs.

DTCs P0506 and P0507 are Type B DTCs.

  1. A stalling condition can cause DTC P0506 to set.
  2. An intermittent vehicle speed sensor (VSS) signal can cause DTC P0507 to set.
  3. An intermittent clutch pedal position sensor signal, if equipped, can cause DTC P0506 to set.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

IMPORTANTThe engine must first be running for greater than 60 seconds, then idle at a steady state for an additional 10 seconds before comparing the actual and desired engine idle speed parameters.
  1. Using a scan tool compare the desired engine idle speed to the actual engine idle speed. Actual engine idle speed should be no greater than 100 RPM below desired. Actual engine idle speed should be no greater than 200 RPM above desired.
  2. If any other DTCs are set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) .
  3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
  1. Inspect for any condition that can reduce idle speed by increasing engine load. Incorrect torque converter clutch (TCC) operation Accessories that require additional torque to operate Excessive deposits in the throttle body Restricted exhaust Mechanical conditions that limit engine speed Repair any conditions, if necessary.
  2. Inspect for the following conditions: Vacuum leaks A faulty positive crankcase ventilation (PCV) valve

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each of the diagnostic category.

This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM) and the throttle actuator control (TAC) system. This diagnostic also addresses if the ECM is not programmed.

The ECM monitors its ability to read and write to the memory. It also monitors a timing function. The ECM and the TAC processors are used to monitor the TAC system data. Both processors monitor the other processors data to verify that the indicated APP calculation is correct. The ECM performs an intrusive test in order to confirm that the APP signals are not shorted together. The ECM accomplishes this by pulling the APP sensor 2 low momentarily and looking for sensor 1 to also be pulled low.

Conditions for Running the DTCs

P0601, P0604

  1. The ignition switch is in Run or Crank.
  2. These DTCs run continuously when the above condition is met.

P0602, P0603, P062F

  1. The ignition switch is in ON.
  2. These DTCs run once per ignition cycle.

P0606, P0607, P060D

  1. The ignition switch is in Run or Crank.
  2. Reduced engine power is not active.
  3. The system voltage is more than 6 V.
  4. These DTCs run continuously when the above conditions are met.

P2610

  1. The intake air temperature is between -40 to +125°C (-40 to +257°F).
  2. DTC P2610 runs once per ignition cycle.

Conditions for Setting the DTCs

The ECM detects an internal failure or incomplete programming for more than 10 s.

Actions Taken When the DTC Sets

  1. DTCs P0601, P0602, P0603, P0604, P0606, P060D, and P062F are Type A DTCs.
  2. DTC P0607 is a Type C DTC.
  3. DTC P2610 is a Type B DTC.
  1. DTCs P0601, P0602, P0603, P0604, P0606, P060D, and P062F are Type A DTCs.
  2. DTC P0607 is a Type C DTC.
  3. DTC P2610 is a Type B DTC.

Low voltage or a momentary loss of power or ground to the ECM may cause a DTC to set. Verify the following

  1. The battery cables are clean and tight, and the battery is fully charged. Refer to «Battery Inspection/Test»(/chevrolet/impala/ix-2006-2016/remont/charging-system/#battery-charging-system-and-starting-system) .
  2. The ECM ground circuits do not have an open or high resistance.
  3. The ECM power circuits do not have an open, short to ground, or high resistance.

Schematic Reference

Connector End View Reference

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. Observe the DTC information with a scan tool. DTC P0601, P0602, P0603, P0604, P0606, P0607, P060D, P062F, or P2610 should not set.
  2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Ignition ON, clear the DTC information with a scan tool. Observe the scan tool DTC information. Verify that DTCs P0601, P0602, P0603, P0604, P0606, P0607, P060D, P062F, or P2610 do not fail this ignition cycle.

  1. If DTC P0602 failed this ignition, reprogram the K20 ECM. Refer to «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for K20 ECM replacement, setup, and programming. If DTC P0602 resets, replace the K20 ECM.
  2. If DTC P0601, P0603, P0604, P0606, P0607, P060D, P062F, or P2610 failed this ignition, replace the K20 ECM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, programming and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

The engine control module (ECM) has 2 internal 5 V reference circuits. Each internal reference circuit provides external 5 V reference circuits for more than one sensor. A short to ground or short to voltage on one external 5 V reference circuit can affect all the components connected to the same internal 5 V reference circuit.

  1. Reduced engine power is not active.
  2. The ignition is ON.
  3. The ignition voltage is greater than 6 V.
  4. The DTCs run continuously when the above conditions are met.

The ECM detects a voltage out of range condition on the 5 V reference 1 or 2 circuit for greater than 0.5 s.

DTCs P0641 and P0651 are Type A DTCs

DTCs P0641 and P0651 are Type A DTCs

The 5 V reference 1 circuit provides 5 V to the following sensors

  1. Manifold absolute pressure (MAP) sensor
  2. Fuel tank pressure (FTP) sensor
  3. Accelerator pedal position (APP) sensor 2
  4. Air conditioning (A/C) refrigerant pressure sensor
  5. Camshaft position sensor
  6. Engine oil pressure sensor

The 5 V reference 2 circuit provides 5 V to the following sensors

  1. APP sensor 1
  2. Crankshaft position sensor
  3. Throttle position sensor 1 and 2

It may be possible to locate the fault by disconnecting one component at a time from the affected 5 V reference circuit while viewing the 5 V Reference circuit status parameter on the scan tool. The scan tool parameter will change from Fault to OK when the source of the fault is disconnected. If all 5 V reference components have been disconnected and a fault is still indicated, the fault may exist in the wiring harness.

Schematic Reference

Connector End View Reference

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. Observe the scan tool 5 V reference 1 circuit status and the 5 V reference 2 circuit status parameters. Verify the parameters display OK.
  2. Ignition ON, observe the DTC information with a scan tool. DTCs P0641 and P0651 should not set.
  3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Note. Additional DTCs will set when disconnecting the components.

  1. Ignition OFF, disconnect the harness connector of all appropriate sensors for the applicable DTC. Refer to Diagnostic Aids for the appropriate sensors.
  2. Ignition ON, measure for 4.8-5.2 V between one of the 5 V reference circuits and ground. If less than the specified range, test for a short to ground on the 5 V reference circuit for each affected component. If all circuits test normal, replace the K20 ECM. If greater than the specified range, test for a short to voltage on the 5 V reference circuit for each affected component. If all circuits test normal, replace the K20 ECM.
  3. Connect each component associated with the 5 V reference circuit, one at a time, while monitoring the appropriate scan tool 5 V Reference Voltage parameter. Verify the voltage remains between 4.8-5.2 V. If not the specified range when a component is connected, test the signal circuit for a short to voltage. If the circuit tests normal, replace the appropriate component.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Accelerator Pedal Position Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  2. «Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning)
  3. «Camshaft Position Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-35l-repair-instructions)
  4. «Crankshaft Position Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-35l-repair-instructions)
  5. «Engine Oil Pressure Sensor and/or Switch Replacement»(/chevrolet/impala/ix-2006-2016/remont/mechanical/#engine-mechanical-39l-repair-instructions-on-vehicle)
  6. «Fuel Tank Pressure Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  7. «Manifold Absolute Pressure Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  8. «Throttle Body Assembly Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  9. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpenShort to Voltage
MIL Voltage SupplyP0650P0650
MIL ControlP0650*P0650P0650
*The MIL remains ON

The malfunction indicator lamp (MIL) is located on the instrument panel cluster (IPC).

The MIL informs the driver that an emission system fault has occurred and that the engine control system requires service. The engine control module (ECM) monitors the MIL control circuit for conditions that are incorrect for the commanded states of the MIL. For example, a failure condition exists if the ECM detects low voltage when the MIL is commanded OFF, or high voltage when the MIL is commanded ON.

  1. The ECM has commanded the MIL ON and OFF at least once during the ignition cycle.
  2. DTC P0650 runs continuously when the ignition is ON.

The ECM detects that the commanded state of the MIL driver and the actual state of the control circuit do not match for more than one second.

DTC P0650 is a Type B DTC.

DTC P0650 is a Type B DTC.

If the condition is intermittent, move the related harnesses and connectors with the engine operating. Monitor the scan tool Circuit Test Status parameters for the component. The Circuit Test Status parameter will change from OK or Not Run to Fault if there is a condition with the circuit or a connection.

Schematic Reference

  1. «Instrument Cluster Schematics»(/chevrolet/impala/ix-2006-2016/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)
  2. «Engine Controls Schematics»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-wiring-schematic-diagrams)

Connector End View Reference

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, command the MIL ON and OFF with a scan tool. The MIL should turn ON and OFF as commanded.
  2. Command the MIL ON and OFF with a scan tool while observing the following control circuit status parameters: MIL Ckt Short Gnd Test Status MIL Ckt Open Test Status MIL Ckt Short Volts Test Status Each parameter should change from OK to Not Run or from Not Run to OK.
  3. Operate the vehicle within the Conditions for Running the DTC to verify that the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
  1. Ignition ON, verify that the (IPC) warning indicators are illuminated. If the IPC warning indicators are not illuminated, test the IPC ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, replace the IPC.
  2. Ignition OFF, disconnect the ECM X1 harness connector. Ignition ON, the MIL should not illuminate. If the MIL is illuminated, test the MIL control circuit terminal 68 for a short to ground. If the circuit tests normal, replace the IPC.
  3. Ignition ON, connect a 3A fused jumper wire between the MIL control circuit terminal 68 and ground. The MIL should illuminate. If the MIL does not illuminate, test the MIL control circuit for a short to voltage, or an open/high resistance. If the circuit tests normal, replace the IPC/bulb.
  4. If all circuits/connections test normal, replace the ECM. Ignition ON, verify that the IPC warning indicators are illuminated.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Instrument Cluster Replacement»(/chevrolet/impala/ix-2006-2016/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)
  2. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to Voltage
Relay Coil Supply VoltageP0685, P0689, P1682
Relay Control CircuitP0690P0685, P0689, P1682P0685, P0689, P1682
Relay Feedback CircuitP0689, P1682P0689, P1682P0690

Powertrain Relay

CircuitShort to GroundOpen/High ResistanceShort to Voltage
Ignition 1 Signal112
1. Will cause a No Crank condition. 2. Engine continues to operate with ignition OFF.

Ignition Main Relay

CircuitShort to GroundOpenShort to Voltage
Operating Conditions: Component commanded OFF Parameter Normal Range: The following illustrates the normal parameter state with no circuit conditions: Component OFF - OK for Open/Short Gnd test and Not Run for Short to Volts test Component ON - Not Run for Open/Short Gnd test and OK for Short to Volts test
Battery VoltageFault
EC Ignition Relay Control CircuitFaultFaultNot Run

EC Ignition Relay Control Ckt Open, Short Gnd, Short Volts Test Status

CircuitShort to GroundOpenShort to Voltage
Operating Conditions: Component commanded ON Parameter Normal Range: The following illustrates the normal parameter state with no circuit conditions: Component OFF - OK for Open/Short Gnd test and Not Run for Short to Volts test Component ON - Not Run for Open/Short Gnd test and OK for Short to Volts test
Battery VoltageNot Run
EC Ignition Relay Control CircuitNot RunNot RunFault

EC Ignition Relay Control Ckt Open, Short Gnd, Short Volts Test Status

There are 2 ignition voltage circuits supplied to the engine control module (ECM). One is supplied by the powertrain relay and the other is supplied by the ignition main relay. The ECM monitors and compares the ignition voltage supplied by the 2 relays.

P0685

  1. The ignition is ON.
  2. Ignition 1 signal voltage is between 11-32 V.
  3. The DTC runs continuously when the above conditions are met.

P0689, P0690

  1. P0685 is not set.
  2. The powertrain relay is commanded on.
  3. The DTC runs continuously when the above conditions are met.

P1682

  1. The powertrain relay is commanded on.
  2. Ignition 1 Signal voltage is greater than 5.5 V.
  3. The DTC runs continuously when the above conditions are met.

P0685

The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than 2 s.

P0689

The ECM detects that the engine controls ignition relay feedback circuit is less than 5 V when the relay is commanded ON.

P0690

  1. The ECM detects the engine controls ignition relay feedback circuit is greater than 2 V when the relay is commanded OFF.
  2. The ECM detects the engine controls ignition relay feedback circuit is greater than 18 V when the relay is commanded ON.
  3. The condition is present for greater than 2 s.

P1682

The ECM detects that the voltage level difference is greater than 3 V between the 2 ignition voltage circuits for less than 1 s.

  1. DTCs P0685 and P0690 are Type B DTCs.
  2. DTC P1682 is a Type A DTC.
  3. DTC P0689 is a Type C DTC.
  1. DTCs P0685 and P0690 are Type B DTCs.
  2. DTC P1682 is a Type A DTC.
  3. DTC P0689 is a Type C DTC.

Schematic Reference

  1. «Engine Controls Schematics»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-wiring-schematic-diagrams)
  2. «Power Distribution Schematics»(/chevrolet/impala/ix-2006-2016/remont/body-electrical/#wiring-systems-and-power-management-wiring-schematics-and-wiring-harness-routing-diagrams)

Connector End View Reference

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Electrical Center Identification Views»(/chevrolet/impala/ix-2006-2016/remont/electrical-component-locations/#wiring-systems-and-power-management-component-locator-electrical-center-identification-views)
  4. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  5. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, command the EC Ignition Relay ON and OFF with a scan tool while observing the following EC Ignition Relay control circuit status parameters: EC Ignition Relay Control Ckt Short Gnd Test Status EC Ignition Relay Control Ckt Open Test Status EC Ignition Relay Control Ckt Short Volts Test Status Each parameter should display OK or Not Run in each commanded state.
  2. Ignition ON, view the DTC information with a scan tool. DTC P0685, P0690, or P1682 should not set.
  3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Note. You must perform the Circuit/System Verification before proceeding with Circuit/System Testing unless sent here from Engine Cranks But Does Not Run.

  1. Ignition OFF, disconnect the KR75 powertrain relay.
  2. Verify a test lamp illuminates between ground and the relay circuit terminals listed below: Terminal 85 Terminal 30 If the test lamp does not illuminate, test the relay battery voltage circuit for an open/high resistance.
  3. Ignition ON, verify that a test lamp does not illuminate between the ignition voltage circuit terminal 87 and ground. If the test lamp illuminates, test the ignition voltage circuit for a short to voltage.
  4. Connect a 20 A fused jumper wire between the relay switch B+ circuit terminal 30 and the relay switch ignition voltage circuit terminal 87.
  5. Ignition ON, observe the scan tool EC Ignition Relay Feedback Signal parameter. The ECM should communicate, and the parameter should display B+. If not the specified value, or the ECM does not communicate, test the ignition voltage circuit between the powertrain relay and the ECM for a short to ground or for an open/high resistance. If the circuit/connections test normal, replace the K20 ECM.
  6. Ignition OFF, connect a DMM set to the diode setting between control circuit terminal 86 and ground. Verify the DMM displays OL. If not the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 ECM.
  7. Ignition ON, verify the DMM displays less than 1 V. If not the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
  8. If all circuits test normal, replace the KR75 powertrain relay.
  1. Test for one of the following resistance specifications between terminals 85 and 86 of the KR75 powertrain relay: 70-110 ohms 200-250 ohms If not within the specified range, replace the KR75 powertrain relay.
  2. Test for infinite resistance between the following terminals of the KR75 powertrain relay: 30 and 86 30 and 87 30 and 85 85 and 87 If not the specified value, replace the KR75 powertrain relay.
  3. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87. If greater than the specified range, replace the KR75 powertrain relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Relay Replacement (Attached to Wire Harness)»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) or «Relay Replacement (Within an Electrical Center)»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  2. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each of the diagnostic category.

This diagnostic trouble code (DTC) indicates that an emission related transmission DTC set in the transmission control module (TCM). The engine control module (ECM) receives the TCM information over the serial data circuit. The ECM turns ON the malfunction indicator lamp (MIL) when the TCM sends a message over the serial data circuit requesting MIL illumination. The DTC information for the ECM will only display DTC P0700, but the Freeze Frame/Failure Records data will display the transmission DTC that set.

  1. The ignition is ON or the engine is operating.
  2. DTC P0700 runs continuously.

The ECM receives a serial data message from the TCM requesting the ECM to turn ON the MIL.

DTC P0700 is a Type A DTC.

DTC P0700 is a Type A DTC.

Communication codes, U-codes, as well as powertrain codes, P-codes, set in the TCM can cause the TCM to request DTC P0700 to be set in the ECM.

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. DTC P0700 is an informational DTC. If there are no engine controls or communication DTCs, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) for diagnosis of TCM DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

The air fuel imbalance monitor (AFIM) diagnostic detects a rich or lean cylinder to cylinder air/fuel ratio imbalance in each bank. The diagnostic monitors the pre-catalyst heated oxygen sensor (HO2S) signal's frequency and amplitude characteristics by calculating an accumulated voltage over a predetermined sample period. An imbalance is indicated when multiple samples of the accumulated voltage are consistently higher than the desired value.

  1. DTCs P0053, P0059, P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0117, P0118, P0120, P0122, P0123, P0128, P0131, P0132, P0133, P0134, P0135, P0151, P0152, P0153, P0154, P0155, P0201-P0206, P0220, P0222, P0223, P0300, P0301-P0306, P0442, P0443, P0446, P0449, P0452, P0453, P0455, P0496, P0606, P0641, P0651, P1133, P1516, P2101, P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2176, P2A00 are not set.
  2. The device control is not active.
  3. The intrusive diagnostics are not active.
  4. The engine overspeed protection is not active.
  5. Reduced engine power is not active.
  6. The traction control is not active.
  7. The engine is in Closed Loop status.
  8. The system voltage is between 10-32 V for greater than 4 s.
  9. The engine run time is greater than 50 seconds.
  10. The engine coolant temperature (ECT) is warmer than -20°C (-4°F).
  11. The engine speed is between 500-4,000 RPM.
  12. The mass air flow is between 5-600 g/s.

Multiple samples of the pre-catalyst HO2S accumulated voltage are consistently higher than the desired value.

DTC P1174 is a Type B DTC.

DTC P1174 is a Type B DTC.

  1. The fuel trim cylinder balance diagnostic is very sensitive to heated oxygen sensor (HO2S) design. A non-OE sensor or an incorrect part number may cause a DTC to set.
  2. Monitoring the misfire current counters, or misfire graph, may help to isolate the cylinder that is causing the condition.
  3. Certain aftermarket air filters may cause a DTC to set.
  4. Certain aftermarket air induction systems or modifications to the air induction system may cause a DTC to set.
  5. Certain aftermarket exhaust system components may cause a DTC to set.

Schematic Reference

Connector End View Reference

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Troubleshooting with a Test Lamp»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. Read and record the Freeze Frame/Failure Records data taking note of the speed and load at which the DTC set.
  2. Diagnose any other DTCs that are set. Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) .
  3. With the engine idling and the transmission in the Park or Neutral position, observe the manifold absolute pressure (MAP) sensor parameter. The MAP sensor parameter should be between 19-42 kPa. If the MAP sensor parameter is not between 19-42 kPa, refer to «DTC P0106»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-dtc-p0010-through-dtc-p0340) or «DTC P0107 or P0108»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-dtc-p0010-through-dtc-p0340) .
  4. Inspect the air induction system for modified, damaged, leaking, or restricted components.
  5. Inspect the crankcase ventilation system for improper operation.
  6. Inspect the vacuum hoses for splits, kinks, and improper connections.
  7. Inspect for vacuum leaks at the intake manifold, the throttle body, and the injector O-rings.
  8. Test for a restricted, damaged, leaking, or modified exhaust system from the catalytic converter forward. Refer to «Symptoms - Engine Exhaust»(/chevrolet/impala/ix-2006-2016/remont/exhaust/#engine-exhaust-system__symptoms-engine-exhaust) .
  9. Test the fuel injectors for improper operation. Refer to «Fuel Injector Diagnosis (J39021 or Tech 2)»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-troubleshooting-diagnosis) or «Fuel Injector Diagnosis (CH47976)»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-troubleshooting-diagnosis) .
  10. Test for fuel contamination. Refer to «Alcohol/Contaminants-in-Fuel Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-troubleshooting-diagnosis) .
  11. Test for excessive fuel in the crankcase due to leaking injectors.
  12. Test the ignition system for improper operation. Refer to «Electronic Ignition System Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-troubleshooting-diagnosis) .
  13. Test the engine for any mechanical conditions such as sticking valves, lifters, etc., which could alter the flow into the combustion chamber. Refer to «Symptoms - Engine Mechanical»(/chevrolet/impala/ix-2006-2016/remont/mechanical/#engine-mechanical-39l-diagnostic-information-and-procedures) .

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verify the repair under the same speed and load as noted in the Freeze Frame/Failure Records data recorded during testing.

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

The catalytic converter must be warmed to efficiently reduce the emissions. The cold start strategy is to reduce the amount of time it takes to warm the catalytic converter. During a cold start, the engine idle speed is elevated and spark timing is retarded to allow the catalyst to warm quickly. This diagnostic monitors the following to build an exhaust energy model

  1. Engine speed
  2. Spark advance
  3. Throttle position
  4. Engine airflow
  5. Engine coolant temperature
  6. Engine runtime
  7. Park/neutral position
  8. Vehicle speed

The actual model is then compared to the expected exhaust energy model.

  1. The engine is running, and a cold start has been detected.
  2. The vehicle speed less than 2 km/h (1 mph).
  3. The engine is at idle with no input from the accelerator pedal.
  4. The airflow is greater than 40 mg/cylinder.
  5. DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0220, P0222, P0223, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0335, P0336, P0351, P0352, P0353, P0501, P0502, P0506, P0507, P0601, P0602, P0603, P0604, P0606, P0607, P060D, P062F, P0641, P0651, P1101, P1516, P1682, P2101, P2119, P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2138, P2176, P2610, P3400 are not set.

This DTC runs for 15 seconds within the first 2 minutes of start-up. This diagnostic runs once per trip when a cold start has been determined.

The actual exhaust energy model does not match the expected exhaust energy model.

DTC P1400 is a Type A DTC.

DTC P1400 is a Type A DTC.

Description and Operation

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

Any loading of the engine that lowers engine RPM, such as with partial application of the clutch, A/C cycling etc. during the first 120 seconds of engine runtime may set this DTC.

  1. Allow the engine to cool.
  2. Start and idle the engine for at least 2 minutes.
  3. DTC P1400 should run and pass.
  1. Inspect the air intake system for the following: Damage, restriction, or modification Dirty or deteriorating air filter element Crankcase ventilation system for correct operation-Refer to «Crankcase Ventilation System Inspection/Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/mechanical/#engine-mechanical-39l-diagnostic-information-and-procedures__crankcase-ventilation-system-inspectiondiagnosis) . Water intrusion Vacuum leak and other un-metered air downstream of the mass air flow (MAF) sensor Intake manifold leak
  2. Inspect the exhaust system for the following: Water intrusion Exhaust leak Damaged, restricted, modified or enhanced exhaust system-Refer to «Symptoms - Engine Exhaust»(/chevrolet/impala/ix-2006-2016/remont/exhaust/#engine-exhaust-system__symptoms-engine-exhaust) .
  3. Inspect the engine mechanical for items that could alter the air flow into the combustion chamber. Refer to «Symptoms - Engine Mechanical»(/chevrolet/impala/ix-2006-2016/remont/mechanical/#engine-mechanical-39l-diagnostic-information-and-procedures) .

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
TAC Motor Control ClosedP1516, P2101, P2176P1516, P2101, P2176P1516, P2101, P2176P1516, P2101, P2176
TAC Motor Control OpenP1516, P2101, P2176P1516, P2101, P2176P1516, P2101, P2176P1516, P2101, P2176

The engine control module (ECM) controls the throttle valve by applying a varying voltage to the control circuits of the throttle actuator control (TAC) motor. The ECM monitors the duty cycle that is required to actuate the throttle valve. The ECM monitors the throttle position (TP) sensors 1 and 2 to determine the actual throttle valve position.

P1516

  1. DTC P0068 or P0121 is not set.
  2. The ignition is in the Run or Crank position.
  3. The ignition voltage is greater than 6.5 V.
  4. The engine is running, or the system is not in the Battery Save mode if the engine is not running.
  5. The DTC runs continuously when the above conditions are met.

P2101

  1. DTC P0068 or P0121 is not set.
  2. The ignition is in the Run or Crank position.
  3. The system voltage is greater than 11 V.
  4. The engine is running or the system is not in Battery Saver mode if the engine is not running.
  5. The DTC runs continuously when the above conditions are met.

P2119

  1. The ignition is in the Unlock/Accessory, Run, or Crank position.
  2. The ignition voltage is greater than 5.23 V.
  3. The system is in the Battery Save mode.
  4. The DTC runs continuously when the above conditions are met.

P2176

  1. The ignition is in the Run or Crank position.
  2. DTC P0120, P0122, P0123, P0220, P0222, P0223, or P2135 is not set.
  3. The system is in the minimum throttle position (TP) learn state.
  4. The throttle is stable for greater than 0.040 s.
  5. The DTC runs continuously when the above conditions are met.

P1516

  1. The indicated throttle position does not match the predicted throttle position for greater than 0.5 s. OR
  2. The ECM detects a current draw of greater than 9 amps on the motor circuits for greater than 0.18 s.

P2101

The indicated throttle position does not match the predicted throttle position for greater than 0.3 s.

P2119

The ECM detects that the throttle is unable to return to the default position after it is de-energized for greater than 0.5 s.

P2176

The ECM detects that the minimum throttle position was not learned for greater than 1.8 s.

  1. DTCs P1516, P2101, and P2176 are Type A DTCs.
  2. DTC P2119 is a Type C DTC.
  3. The ECM commands the TAC system to operate in the Reduced Engine Power mode.
  1. DTCs P1516, P2101, and P2176 are Type A DTCs.
  2. DTC P2119 is a Type C DTC.
  1. If the Throttle Sweep Test is not available on the scan tool, observe the scan tool TAC Motor parameter while performing the following tests: Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure several times. The TAC Motor parameter should display Enabled. If Disabled is displayed, continue diagnosis in Circuit/System Testing.
  2. Inspect for a condition in which the throttle valve may have been held open. For example, ice may have formed in the throttle bore causing the throttle valve not to close.
  3. A high resistance condition on the throttle position and throttle actuator control circuits could cause a DTC to set.
  4. A low battery condition may cause a DTC to set.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the DTC information with a scan tool. DTC P0120, P0122, P0123, P0220, P0222, P0223, P0562, P0621, P0622, or P2135 should not set. If a DTC sets, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) for further diagnosis.
  2. Clear the DTCs with a scan tool. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down.
  3. Ignition ON, observe the scan tool TAC Motor parameter. The reading should display Enabled.
  4. Observe the DTC information with a scan tool. DTC P1516, P2101, P2119, or P2176 should not set.
  5. Perform the Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should display Enabled while the Throttle Sweep Test is in progress. NOTE: Before replacing the throttle body assembly, make sure the throttle control circuits are not shorted to B+. If not the specified value, replace the throttle body assembly.
  6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
WARNINGTurn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.
  1. Ignition OFF, inspect the throttle body for the following conditions: A throttle blade that is not in the rest position A throttle blade that is binding open or closed A throttle blade that is free to move open or closed without spring pressure If a condition is found, replace the throttle body assembly.
  2. Ignition OFF, disconnect the harness connector at the throttle body.
  3. Ignition ON, verify that a test lamp does not illuminate between each control circuit listed below and ground. TAC Motor Control Closed circuit terminal A TAC Motor Control Open circuit terminal B If test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. Ignition ON, verify that a test lamp does not illuminate between each control circuit listed below and B+. TAC Motor Control Closed circuit terminal A TAC Motor Control Open circuit terminal B If the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.
  5. Ignition OFF, set the DMM to the 40 V scale, select the Min/Max Recording Mode, and set the Peak Min/Max response time to 1 ms.
  6. Ignition OFF, measure the voltage using the DMM Min/Max Recording Mode function on each circuit listed below as the ignition is turned ON. The Max voltage should be within 1 V of B+. TAC Motor Control Closed circuit terminal A TAC Motor Control Open circuit terminal B If not within the specified range, test the circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
  7. If all circuits and connections test normal, replace the throttle body assembly.
  1. «Throttle Body Assembly Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  2. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
  1. Install any components that have been removed or replaced during diagnosis.
  2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.
  3. Clear the DTCs with a scan tool.
  4. Turn OFF the ignition for 60 seconds.
  5. Perform the Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should display Enabled while the Throttle Sweep Test is in progress.
  6. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the «Diagnostic Trouble Code (DTC) List - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) and perform the appropriate diagnostic procedure.
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
APP Sensor 1 SignalP2122P2122P2123
APP Sensor 1 5-Volt ReferenceP0651P2122P0651
APP Sensor 1 Low ReferenceP2123
APP Sensor 2 SignalP2127P2127P2128
APP Sensor 2 5-Volt ReferenceP0452, P0522, P0532, P0641P2127P0108, P0522, P0533, P0641
APP Sensor 2 Low ReferenceP2128
CircuitShort to GroundOpenShort to Voltage
Operating Conditions: The engine is operating at idle Parameter Normal Range APP Sensor 1: 0.33-4.59 V
5-Volt Reference 10 V0 V5 V
APP Sensor 1 Signal0 V0 V5 V
APP Sensor 1 Low Reference4.96 V

APP Sensor 1

CircuitShort to GroundOpenShort to Voltage
Operating Conditions: The engine is operating at idle Parameter Normal Range APP Sensor 2: 0.16-2.30 V
5-Volt Reference 20 V0 V5 V
APP Sensor 2 Signal0 V0 V5 V
APP Sensor 2 Low Reference4.92 V

APP Sensor 2

The throttle actuator control (TAC) system uses two accelerator pedal position (APP) sensors to monitor the accelerator pedal position. The APP sensors 1 and 2 are located within the pedal assembly. Each sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit.

Two processors are also used to monitor the TAC system data. Both processors are located within the engine control module (ECM). Each signal circuit provides both processors with a signal voltage proportional to pedal movement. The processors share and monitor data to verify that the indicated APP calculation is correct.

P2120, P2122, P2123, P2125, P2127, P2128

  1. The system voltage is greater than 5.23 volts.
  2. The ignition is in the Unlock/Accessory, Run, or Crank position.
  3. DTC P0641, P0651, or P0606 is not set.
  4. The DTCs run continuously when the above conditions are met.

P2138

  1. The system voltage is greater than 5.23 volts.
  2. The ignition is in the Unlock/Accessory or Run position.
  3. DTC P0641, P0651, P0606, P2120, P2122, P2123, P2125, P2127, or P2128 is not set.
  4. The DTC runs continuously when the above conditions are met.

P2120

The ECM detects that APP sensor 1 voltage is less than 0.33 volt or greater than 4.59 volts for greater than 0.5 second.

P2122

The ECM detects that APP sensor 1 voltage is less than 0.33 volt for greater than 0.5 second.

P2123

The ECM detects that APP sensor 1 voltage is greater than 4.59 volts for greater than 0.5 second.

P2125

The ECM detects that APP sensor 2 voltage is less than 0.16 volt or greater than 2.30 volts for greater than 0.5 second.

P2127

The ECM detects that APP sensor 2 voltage is less than 0.16 volt for greater than 0.5 second.

P2128

The ECM detects that APP sensor 2 voltage is greater than 2.30 volts for greater than 0.5 second.

P2138

The ECM detects that the difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value for greater than 0.5 second.

  1. DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.
  2. The ECM commands the TAC system to operate in Reduced Engine Power mode.

DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/chevrolet/impala/ix-2006-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the scan tool APP sensor 1 voltage parameter. The reading should be between 0.13-4.87 volts, and change with the accelerator pedal input.
  2. Ignition ON, observe the scan tool APP sensor 2 voltage parameter. The reading should be between 0.13-4.87 volts, and change with the accelerator pedal input.
  3. Ignition ON, observe the scan tool APP sensor 1 and 2 parameter. The scan tool should indicate agree.
  4. Clear the DTCs with the scan tool.
  5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
  6. Verify that the following DTCs are not set: DTC P0641, P0651, P2120, and P2125. If either or both DTCs P2120 or P2125 are set and they are the only DTCs set, replace the ECM. If DTCs P0641 or P0651 are set, refer to «DTC P0641 or P0651»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-dtc-p0341-through-dtc-p2544) .
  1. Ignition OFF for 90 seconds, disconnect the harness connector at the accelerator pedal.
  2. Test for less than 3 ohms of resistance between each low reference circuit terminals A and D and ground. If greater than 3 ohms, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
  3. Ignition ON, test for 4.8-5.2 volts between each 5-volt reference circuit terminals C and F and ground. If less than 4.8 volts, test affected 5-volt reference circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the ECM. If greater than 5.2 volts, test affected 5-volt reference circuit for short to voltage. If the circuit tests normal, replace the ECM.
  4. Ignition ON, verify the scan tool APP sensor 1 and 2 voltages are less than 0.1 volt. If greater than 0.1 volt, test the APP sensor 1 and 2 signal circuits terminals B and E for a short to voltage. If the circuit tests normal, replace the ECM.
  5. Install a 3A fused jumper wire between the signal circuit terminal E and the 5-volt reference circuit terminal F of the APP sensor 1, verify the APP sensor 1 voltage is greater than 4.8 volts. If less than 4.8 volts, test the APP sensor 1 signal circuit for an open or short to ground. If the circuit tests normal, replace the ECM.
  6. Install a 3A fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal C of the APP sensor 2. Verify that the APP sensor 2 voltage is greater than 4.8 volts. If less than 4.8 volts, test the APP sensor 2 signal circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the ECM.
  7. Ignition OFF for 90 seconds, disconnect the harness connector at the ECM.
  8. Test for less than 5 ohms of resistance on all APP sensor circuits between the following terminals: ECM X1 low reference circuit terminal 37 to APP connector terminal A ECM X1 low reference circuit terminal 36 to APP connector terminal D ECM X1 signal circuit terminal 47 to APP connector terminal E ECM X1 signal circuit terminal 49 to APP connector terminal B ECM X1 5-volt reference circuit terminal 35 to APP connector terminal C ECM X1 5-volt reference circuit terminal 33 to APP connector terminal F If greater than 5 ohms, repair the affected circuit.
  9. Test for infinite resistance between APP sensor 1 signal circuit terminal E and APP sensor 2 signal circuit terminal B. If less than infinite resistance, repair the short between APP sensor 1 signal circuit and APP sensor 2 signal circuits. If all circuits test normal, replace the accelerator pedal.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Accelerator Pedal Position Sensor Replacement»(/chevrolet/impala/ix-2006-2016/remont/testing-diagnostics/#engine-controls-and-fuel-39l-repair-instructions)
  2. «Control Module References»(/chevrolet/impala/ix-2006-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/impala/ix-2006-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

To improve shift feel, the transmission control module (TCM) may request that the engine control module (ECM) reduce engine torque during shift events. When such a request is received, the ECM responds by retarding the base ignition timing and notifying the TCM that the request has succeeded. If the ECM is unable to comply with the request, the ECM sends the TCM a message that the request has failed.

The torque reduction request is sent to the ECM through a communication network called the controller area network (CAN). Two circuits are used to communicate CAN data between the ECM and TCM. A fault in the CAN will not cause DTC P2544 to set by itself. If a CAN fault occurs, other DTCs will set before DTC P2544.

When the TCM receives a torque reduction failure message from the ECM, then DTC P2544 will set. DTC P2544 is a type B DTC.

  1. The engine run time is greater than 5 seconds.
  2. No other CAN errors are present.

The ECM notifies the TCM that a torque reduction request has failed for 2 seconds.

  1. DTC P2544 is a Type B DTC.
  2. The TCM commands maximum line pressure.
  3. The TCM freezes transmission adaptive functions.
  4. At the time of the first failure, the TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as a Failure Record.
  5. At the time of the second failure, the ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as a Freeze Frame.
  6. The TCM stores DTC P2544 in TCM history.
  1. DTC P2544 is a Type B DTC.
  2. The ECM turns OFF the malfunction indicator lamp (MIL) after the sixth consecutive drive trip in which the TCM does not send a MIL illumination request.
  3. A scan tool can clear the DTC.
  4. The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring.
  5. The TCM cancels the DTC default actions when the ignition is OFF long enough in order to power down the TCM.

This DTC may set due to low system voltage. Ensure that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test . Verify the charging system is operating correctly. Refer to Charging System Test . Verify there is no parasitic drain on the battery. Refer to Battery Electrical Drain/Parasitic Load Test .

DTC Type Reference

Observe the DTCs with the scan tool.

  1. If DTC P0604 is set, replace the ECM.
  2. If DTC P0604 is not set, replace the TCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM or TCM replacement, setup, and programming

See also:
• Diagnostic System Check - Vehicle
• Strategy Based Diagnosis
• Diagnostic Procedure Instructions
• Engine Controls Schematics
• Component Connector End Views -- Index
• Electronic Ignition System Description
• Circuit Testing
• Connector Repairs
• Wiring Repairs
• Control Module References
• Engine Mechanical Specifications
• Camshaft Timing Chain and Sprocket Cleaning and Inspection
• Camshaft and Bearings Cleaning and Inspection
• Diagnostic Repair Verification
• Camshaft Position Sensor Replacement
• Ignition Coil Replacement
• Diagnostic Trouble Code (DTC) List - Vehicle
• Exhaust Leakage
• Restricted Exhaust
• Evaporative Emission System Diagnosis
• Testing for Intermittent Conditions and Poor Connections
• Throttle Body Inspection and Cleaning
• Battery Inspection/Test
• Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement
• Engine Oil Pressure Sensor and/or Switch Replacement
• Instrument Cluster Schematics
• Power Distribution Schematics
• Electrical Center Identification Views
• Relay Replacement (Attached to Wire Harness)
• DTC P0106
• Symptoms - Engine Exhaust
• Fuel Injector Diagnosis (J39021 or Tech 2)
• Symptoms - Engine Mechanical
• Engine Control Module Description
• Crankcase Ventilation System Inspection/Diagnosis
• DTC P0641 or P0651

More articles — Engine Performance