Engine Controls and Fuel - 6.2l - Symptom Troubleshooting and Diagnosis Cadillac CTS II

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.

Symptoms Description

Symptoms covers conditions that are not covered by DTCs. Certain conditions can cause multiple symptoms. These conditions are listed together under Symptoms Testing. Conditions that may only cause specific symptoms are listed separately under Additional Symptoms Testing. Perform the Symptoms Testing before using the Additional Symptoms Testing.

Symptoms Verification

Before using the Symptom tables, perform the following inspections

1. Ensure that the malfunction indicator lamp (MIL) is operating correctly. Use the scan tool to command the lamp ON and OFF.
2. Ensure that there are no DTCs that are stored.
3. Ensure that the scan tool data is within a normal operating range. Refer to «Control Module References»(/cadillac/cts/ii-2007-2014/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for scan tool information.
4. Verify the customer concern.
5. Perform the Visual/Physical Inspection in this section. The visual/physical inspection is extremely important, and can lead to correcting a condition without additional testing. It may also help reveal the cause of an intermittent condition.

Identifying Intermittent Conditions

Many intermittent conditions occur with harness or connector movement due to engine torque, rough pavement, vibration or physical movements of a component. Refer to the following for a list of issues that may cause an intermittent condition

1. Moisture and water intrusion in connectors, terminals, and components
2. Incomplete connector mating
3. Poor terminal contact
4. High circuit or component resistance-High resistance can include any resistance, regardless of the amount, which can interrupt the operation of the component.
5. Harness that is too short or tight
6. Wire insulation that is chaffed or cut
7. High or low ambient temperature
8. High or low engine coolant temperatures
9. High underhood temperatures
10. Heat build up in component or circuit due to circuit resistance, poor terminal contact, or high electrical load
11. High or low system voltage
12. High vehicle load conditions
13. Rough road surfaces
14. Electro-magnetic interference (EMI)/circuit interference from relays, solenoids or other electrical surge
15. Incorrect installation of aftermarket, add on accessories

Visual/Physical Check

1. Ensure that the control module grounds are clean, tight, and correctly located.
2. Ensure that the vacuum hoses are not split or kinked, and are properly connected, as shown on the Vehicle Emission Control Information label.
3. Ensure that the air filter is clean and free from restrictions.
4. Ensure that there is no water intrusion in connectors terminals and components.
5. Inspect the air intake ducts for the following conditions: Collapsed Damaged areas Looseness Incorrect installation Leaking
6. Inspect for air leaks at the throttle body mounting area, the mass air flow (MAF) sensor and intake manifold sealing surfaces.
7. Inspect the wiring harness for the following conditions: Poor connections Pinches Cuts
8. Inspect for loose, damaged, unseated, or missing sensors/components.
9. Inspect the terminals for corrosion and correct contact.

Symptoms Testing

Backfire, Cuts Out/Misses, Detonation/Spark Knock, Dieseling/Run-On, Hard Start, Hesitation/Sag/Stumble, Lack of Power/Sluggishness/Sponginess, Poor Fuel Economy, Rough, Unstable, or Incorrect Idle and Stalling, or Surges/Chuggles

1. Test the fuel system for the following: The fuel system for correct operation volume and pressure-Refer to «Fuel System Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) . The fuel injectors for proper operation-Refer to «Fuel Injector Diagnosis (w/J39021 or w/Tech 2)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) or «Fuel Injector Diagnosis (w/CH47976)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) . The fuel quality condition-Refer to «Alcohol/Contaminants-in-Fuel Diagnosis (without Special Tool)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) or «Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .
2. Test ignition system for the following: Spark plugs for incorrect heat range or an abnormal condition-Refer to «Spark Plug Inspection»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__spark-plug-inspection) and «Ignition System Specifications»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-specifications__ignition-system-specifications) . For diagnosis of coolant or oil fouled spark plugs-Refer to «Coolant in Combustion Chamber»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-diagnostic-information-and-procedures__coolant-in-combustion-chamber) or «Oil Consumption Diagnosis»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-diagnostic-information-and-procedures__oil-consumption-diagnosis) . Wet down the secondary ignition system with water from a spray bottle-Wetting down the secondary ignition system may help locate damaged or deteriorated components. Look/listen for arcing or misfiring as the water is applied. Weak spark using the J 26792 Spark Tester-Refer to «Electronic Ignition System Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .
3. Inspect for the following conditions: The proper operation of the transmission torque converter clutch (TCC) - The scan tool should indicate an engine speed drop when the TCC is commanded ON. Refer to «Torque Converter Diagnosis»(/cadillac/cts/ii-2007-2014/remont/automatic-trans/#automatic-transmission-6l456l506l806l90-symptom-troubleshooting-and-diagnosis) . The proper operation of the A/C compressor. An engine that runs lean or rich. Observe the Fuel Trim parameters with a scan tool. Inspect the heated oxygen sensors (HO2S). The HO2S should respond quickly to different throttle positions. CAUTION: Refer to «Heated Oxygen and Oxygen Sensor Caution»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#dangers-warnings-and-cautions__heated-oxygen-and-oxygen-sensor-caution) . Water intrusion in the HO2S connector NOTE: The embossed arrows on the mass air flow (MAF) sensor indicate the direction of the intake air flow. The arrows must point toward the engine. Inspect the MAF sensor installation. A MAF sensor that is incorrectly installed may cause a hard start. Install the MAF in the proper direction. Refer to «Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LSA)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-repair-instructions) . Inspect the mass air flow (MAF) sensor connections. Engine oil contaminated by fuel Vacuum hoses for splits or kinks-Verify that the routing and connections are as shown on the Vehicle Emission Control Information label. Knock sensor (KS) system for excessive spark retard activity-Observe the Knock Retard parameter on the scan tool for activity more than 0°.
4. The exhaust system components for the following: Physical damage or possible internal failure The three-way catalytic converters for a restriction For more information, refer to «Symptoms - Engine Exhaust»(/cadillac/cts/ii-2007-2014/remont/exhaust/#engine-exhaust-system__symptoms-engine-exhaust) .
5. Electromagnetic interference (EMI) on the reference circuit can cause a misfire condition. You can usually detect EMI with a scan tool by monitoring the engine speed parameter. A sudden increase in the engine speed parameter with little change in actual engine speed indicates that EMI is present. Inspect the high voltage components near the ignition control circuit if a condition exists.
6. The crankcase ventilation valve for proper operation-Refer to «Crankcase Ventilation System Inspection/Diagnosis»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-diagnostic-information-and-procedures__crankcase-ventilation-system-inspectiondiagnosis) .
7. Evaporative emission (EVAP) canister purge solenoid that is stuck open
8. The engine cooling system for the following conditions: The thermostat is the correct heat range. Refer to «Thermostat Diagnosis»(/cadillac/cts/ii-2007-2014/remont/cooling-system-mechanical/#engine-cooling-system__thermostat-diagnosis-lsa) . Proper engine coolant level-If the level is low, refer to «Loss of Coolant»(/cadillac/cts/ii-2007-2014/remont/cooling-system-mechanical/#engine-cooling-system__loss-of-coolant) .
9. The crankshaft position (CKP) sensor for an intermittent condition-Observe the scan tool CKP Resync parameter. The Resync parameter should remain at 0 during all operating conditions, and when moving the related harnesses and connectors between the CKP sensor and the ECM.
10. Inspect the engine for the following mechanical failures: Refer to «Symptoms - Engine Mechanical»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-diagnostic-information-and-procedures) . Excessive oil in the combustion chamber or leaking valve seals Oil Consumption Incorrect cylinder compression Sticking or leaking valves Worn camshaft lobes Incorrect valve timing Worn rocker arms Broken valve springs Excessive carbon buildup in the combustion chambers-Clean the chambers with top engine cleaner. Follow the instructions on the can. Incorrect engine parts
11. If the above conditions do not address the symptom, refer to the additional symptoms tests.

Additional Symptoms Tests

Hard Start

1. Observe the Throttle Body Idle Airflow Compensation parameter with a scan tool. A value greater than 80% may indicate an excessive accumulation of deposits in the throttle bore. Inspect the throttle body and clean, if necessary. Refer to «Throttle Body Cleaning»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__throttle-body-cleaning) .
2. Test the engine coolant temperature (ECT) sensor. Compare the ECT sensor value to the intake air temperature (IAT) sensor value on a cold engine. The ECT and IAT sensor values should be within ± 3°C (5°F). If the ECT sensor is out of range with the IAT sensor, test the resistance of the ECT sensor. Refer to «Temperature Versus Resistance - Engine Coolant Temperature Sensor»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-specifications__temperature-versus-resistance-engine-coolant) for resistance specifications. Replace the ECT sensor if the resistance is not within specification. Refer to «ENGINE COOLANT TEMPERATURE SENSOR REPLACEMENT»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions) . If the sensor is within the specification, test the ECT sensor circuits for high resistance.
3. Verify that the fuel system has adequate pressure for engine start-up. Refer to «Fuel System Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) for fuel pressure specifications.
4. Inspect for excessive crankshaft endplay that will cause the crankshaft position (CKP) sensor reluctor wheel to move out of alignment with the CKP sensor. Refer to «Crankshaft and Bearing Cleaning and Inspection»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-repair-instructions-off-vehicle-1-of-3__crankshaft-and-bearing-cleaning-and-inspection) .

Hesitation, Sag, Stumble

1. Test the fuel pressure. Refer to «Fuel System Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .
2. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LSA)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-repair-instructions) .
3. Test the generator. Refer to «Symptoms - Engine Electrical»(/cadillac/cts/ii-2007-2014/remont/charging-system/#battery-charging-system-and-starting-system__symptoms-engine-electrical) . Repair the charging system if the generator output voltage is less than 9 volts or more than 16 volts.
4. Inspect for excessive crankshaft endplay that will cause the crankshaft position (CKP) sensor reluctor wheel to move out of alignment with the CKP sensor. Refer to «Crankshaft and Bearing Cleaning and Inspection»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-repair-instructions-off-vehicle-1-of-3__crankshaft-and-bearing-cleaning-and-inspection) .
5. Test the manifold absolute pressure (MAP) sensor. Refer to «DTC P0106»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-dtc-p0016-dtc-p0208) .

Poor Fuel Economy

1. Heavy loads being carried or towed
2. Acceleration rate too much or too often
3. Inspect the brake system for brake drag.
4. Inspect for incorrect operation of the speedometer.
5. Verify that the engine coolant temperature (ECT) has not shifted in value. Allow the engine to run and reach operating temperature. Observe the ECT Sensor parameter with a scan tool and compare the reading to that parameter listed on the «Engine Control Module Scan Tool Information (V8)»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-scan-tool-information__engine-control-module-scan-tool-information) list. If the reading is not in the range specified in the list, test the resistance of the ECT sensor. Refer to «Temperature Versus Resistance»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-specifications__temperature-versus-resistance) for resistance specifications. Replace the ECT sensor if the resistance is not within specification. Refer to «Engine Coolant Temperature Sensor Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions) . If the sensor is within the specification, test the ECT sensor circuits for high resistance.
6. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LSA)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-repair-instructions) .
7. Observe the Throttle Body Idle Airflow Compensation parameter with a scan tool. A value greater than 80% may indicate an excessive accumulation of deposits in the throttle bore. Inspect the throttle body and clean, if necessary. Refer to «Throttle Body Cleaning»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__throttle-body-cleaning) .

Detonaton/Spark Knock

1. Inspect for excessive carbon buildup in the combustion chambers. Clean the chambers with Top Engine Cleaner. Follow the instructions on the can.
2. Test for an engine overheating condition. Refer to «Engine Overheating (LSA)»(/cadillac/cts/ii-2007-2014/remont/cooling-system-mechanical/#engine-cooling-system__engine-overheating-lsa) .
3. Verify that the engine coolant temperature (ECT) has not shifted in value. Allow the engine to run and reach operating temperature. Observe the ECT Sensor parameter with a scan tool and compare the reading to that parameter listed on the «Engine Control Module Scan Tool Information (V8)»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-scan-tool-information__engine-control-module-scan-tool-information) list. If the reading is not in the range specified in the list, test the resistance of the ECT sensor. Refer to «Temperature Versus Resistance»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-specifications__temperature-versus-resistance) for resistance specifications. Replace the ECT sensor if the resistance is not within specification. Refer to «Engine Coolant Temperature Sensor Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions) . If the sensor is within the specification, test the ECT sensor circuits for high resistance.
4. If there are no engine mechanical faults, fill the fuel tank with a known high quality fuel that meets the vehicle minimum octane requirements.

Lack of Power, Hesitation, or Cut Out

1. Inspect for a supercharger condition. Refer to «Supercharger Noise Diagnosis»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-diagnostic-information-and-procedures__supercharger-noise-diagnosis) .
2. Inspect the engine electrical system for correct operation. Refer to «Symptoms - Engine Electrical»(/cadillac/cts/ii-2007-2014/remont/charging-system/#battery-charging-system-and-starting-system__symptoms-engine-electrical) .
3. Verify that each injector harness is connected to the correct injector.
4. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LSA)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-repair-instructions) .

Rough, Unstable, or Incorrect Idle and Stalling

1. Observe the Throttle Body Idle Airflow Compensation parameter with a scan tool. A value greater than 80% may indicate an excessive accumulation of deposits in the throttle bore. Inspect the throttle body and clean, if necessary. Refer to «Throttle Body Cleaning»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__throttle-body-cleaning) .
2. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LSA)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-repair-instructions) .
3. Inspect the engine mounts.
4. Inspect the intake and exhaust manifolds for casting flash.

Surges/Chuggles

1. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LSA)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-repair-instructions) .
2. Test the heated oxygen sensors (HO2S). The HO2S should respond quickly to a change in throttle position. If the HO2S do not respond to different throttle positions, inspect for contamination from fuel, silicon, or the incorrect use of RTV sealant. The sensors may have a white powdery coating and result in a high, but false, signal voltage, which gives a rich exhaust indication. The PCM reduces the amount of fuel delivered to the engine, causing a driveability condition.
3. Verify that each injector harness is connected to the correct injector.

Fuel Odor

1. Saturated EVAP canister-Refer to «Evaporative Emission Control System Description»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-description-and-operation) .
2. A condition with the internal components of the fuel tank assembly-Refer to «Fuel System Description»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-description-and-operation) .
3. Inspect for damaged or deteriorated fuel lines.

ECM Commanded Reduced Engine Power

Review the Reduced Engine Power Indication History parameter with a scan tool to determine the reason for the last reduced engine power event.

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Circuit Description

Supercharger boost pressure is regulated under certain conditions to prevent engine and drive train damage. When the engine is operating under high boost conditions, the engine control module (ECM) can limit boost pressure to 83 kPa (12 psi) or less.

The ECM disables boost under the following conditions

1. Reverse gear is selected.
2. An intercooler pump failure is detected.
3. Electronic throttle control (ETC) fault is detected.
4. Intake air temperature (IAT) sensor 2 is equal to or greater than 120.5°C (248°F) boost pressure is limited to 145 kPa (7 psi). The ECM commands the boost control solenoid to 62 percent duty cycle (DC).
5. Engine coolant temperature (ECT) is greater than 125°C (257°F).
6. Drivetrain abuse is detected.
7. Vehicle speeds exceed 256 km/h (159 mph) in second, third, and fourth gears only, after 150 seconds boost is trimmed actively.

The ECM controls boost pressure by a pulse-width ground signal to the boost control solenoid. The boost control solenoid is a normally open valve. Under most conditions, the ECM commands the boost control solenoid to operate at a 99-100 percent DC. This keeps the boost control solenoid valve closed and allows only inlet vacuum from the supercharger plenum to the bypass valve actuator to control the position of the bypass valve. At idle, engine vacuum is applied to the upper side of the bypass valve actuator, counteracting spring tension to hold the bypass valve open. When the engine load is increased, the engine vacuum is decreased, causing the spring in the bypass valve actuator to overcome the applied vacuum, closing the bypass valve and allowing the boost pressure to increase. The bypass valve starts to close when the vacuum measure is 250 mm Hg (10 in Hg) and is fully closed at 90 mm Hg (3.5 in Hg). When reduced boost pressure is desired, the ECM commands the boost control solenoid to operate at a 0 percent DC, but may command a partial duty cycle, approximately 62 percent, depending on the operating conditions. This opens the boost control solenoid and allows boost pressure to enter the bypass valve actuator at the lower side to counteract the spring tension, opening the bypass valve, and re-circulating excess boost pressure back into the supercharger inlet.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

1. «Supercharger Description and Operation»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-description-and-operation)
2. «Boost Control System Description»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-description-and-operation)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

1. J-23738-A Mityvac
2. J-35555 Metal Mityvac

Circuit/System Verification

1. Review the vacuum schematics in the Boost Control System Description. Refer to «Boost Control System Description»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-description-and-operation) .
2. Ignition OFF, visually and physically inspect the supercharger components for any of the following conditions: Inspect the vacuum lines for: Cracking Loose fit Improper connections Improper routing Restrictions
3. Inspect the following components for damage, and for improper connections, improper adjustments, and improper installation: The bypass valve actuator The boost control solenoid The bypass valve lever The bypass valve cable. If a condition is found, refer to «Supercharger Cleaning and Inspection»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-repair-instructions-off-vehicle-2-of-3__supercharger-cleaning-and-inspection) .
4. Verify that the charge air cooler (CAC) coolant level is full. Refer to «Charge Air Cooling System Coolant Level Inspection»(/cadillac/cts/ii-2007-2014/remont/cooling-system-mechanical/#engine-cooling-system__charge-air-cooling-system-coolant-level) .
5. Ignition ON, command the CAC coolant pump ON and OFF with a scan tool. Listen for the CAC coolant pump to turn ON and OFF with each command. If the CAC coolant pump does not turn ON and OFF refer to «Supercharger Intercooler Relay Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .
6. Engine running, command the supercharger bypass (SCB) solenoid from 0 to 90 percent with a scan tool. Observe the operation of the bypass valve, it should move as the DC percentages are varied.
7. Verify there are no vacuum leaks at the supercharger manifold gaskets and supercharger intake plenum.

Circuit/System Testing

1. Ignition OFF, disconnect the boost source hose from the boost control solenoid, connect the J-35555 to the boost source hose.
2. Engine running, observe the gauge on the J-35555 or J-23738-A for a reading equal to or greater then 15 inch Hg. If less than 15 inch Hg, repair the boost vacuum source hose or the intake manifold port for a restriction or blockage.
3. Ignition OFF, connect the vacuum source hose to the boost solenoid.
4. Disconnect the boost signal hose from the bottom port of the bypass valve actuator and connect the J-35555 or J-23738-A to the boost signal hose.
5. Engine running, observe the gauge on the J-35555 or J-23738-A for a reading of 0-1 inch Hg. If greater than the specified range, replace the boost control solenoid.
6. Engine running, command the boost control solenoid to 0% DC with a scan tool. Observe the gauge on the J-35555 or J-23738-A for a reading equal to or greater than 15 inch Hg. If less than the specified range, test the boost signal hose for a restriction or blockage. If the boost signal hose tests normal, replace the boost control solenoid.
7. Disconnect the inlet vacuum signal hose from the top of the bypass valve actuator, and connect J-35555 or J-23738-A to the inlet vacuum signal hose.
8. Engine running, observe the gauge on the J-35555 or J-23738-A for a reading equal to or greater than 15 inch Hg. If less than 15 inch Hg, repair the inlet vacuum signal hose or the intake manifold port for a restriction or blockage.

Component Testing

1. Ignition OFF, disconnect the inlet vacuum signal hose from the top of the bypass valve actuator.
2. Connect J-35555 or J-23738-A to the inlet vacuum signal port at the bypass valve actuator.
3. Slowly apply 15 inch Hg of vacuum while observing the bypass valve actuator. The bypass valve actuator should retract. If the bypass valve actuator and linkage do not retract, inspect the bypass valve actuator and linkage for binding, sticking, or damage. If the bypass valve linkage operate normally, replace the bypass valve actuator.
4. Connect the inlet vacuum signal hose to the top of the bypass valve actuator.
5. Disconnect the boost signal hose from the bottom of the bypass valve actuator, and connect J-35555 or J-23738-A to the boost signal port on the bypass valve actuator.
6. Start and idle the engine in park.
7. Slowly apply vacuum until you reach 20 inch Hg, and observe the bypass valve actuator. The bypass valve actuator should extend. If the bypass valve actuator does not extend, inspect the bypass valve and linkage for binding, sticking, or damage. If the bypass valve and linkage operate normally, replace the bypass valve actuator.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Charge Air Bypass Regulator Solenoid Valve Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)
2. «Supercharger Bypass Valve Actuator Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The supercharger intercooler relay is a normally open relay. The relay armature is held in the open position by spring tension. The ignition 1 voltage is supplied directly to the relay coil and to the armature contact when the ignition is ON, or the engine is running. The engine control module (ECM) supplies the ground path to the relay coil control circuit via an internal integrated circuit called an output driver module (ODM). When the engine is running, the ECM commands the relay ON, and the relay coil creates an electromagnetic field. This electromagnetic field overcomes the spring tension and pulls the armature contact into the stationary contact of the relay load circuit. The closing of the relay contacts allow current to flow from the battery to the supercharger intercooler pump. When the ignition switch is turned to the OFF position, power is interrupted to the output driver module in the ECM and the relay electromagnetic field collapses. This allows the spring tension to separate the relay armature contact from the relay load circuit contact, which interrupts current flow to the supercharger intercooler pump.

Diagnostic Aids

1. A slight resistance of 1-4ohms on the B+ or ground circuits to the CAC coolant pump or the CAC coolant pump relay may inhibit the supercharger coolant pump operation.
2. This test procedure assumes that the vehicle battery has passed a load test and is completely charged. Refer to «Battery Inspection/Test»(/cadillac/cts/ii-2007-2014/remont/charging-system/#battery-charging-system-and-starting-system) .
3. When disconnecting electrical connectors or removing fuses and relays from a fuse block, always inspect the component electrical terminals for corrosion and the mating electrical terminals for correct tension.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

1. «Supercharger Description and Operation»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-description-and-operation)
2. «Boost Control System Description»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-description-and-operation)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
5. «Electrical Center Identification Views»(/cadillac/cts/ii-2007-2014/remont/electrical-component-locations/#wiring-systems-and-power-management-component-locator-electrical-center-identification-views)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 43244 Relay Puller Pliers

1. Ignition ON, command the CAC Coolant Pump ON and OFF with a scan tool. Listen for the CAC coolant pump to turn ON and OFF with each command.
2. Verify that the charge air cooler (CAC) coolant level is full. Refer to «Charge Air Cooling System Coolant Level Inspection»(/cadillac/cts/ii-2007-2014/remont/cooling-system-mechanical/#engine-cooling-system__charge-air-cooling-system-coolant-level) and «Charge Air Cooling System Draining and Filling (Static)»(/cadillac/cts/ii-2007-2014/remont/cooling-system-mechanical/#engine-cooling-system__charge-air-cooling-system-draining-and) or «Charge Air Cooling System Draining and Filling (GE 47716)»(/cadillac/cts/ii-2007-2014/remont/cooling-system-mechanical/#engine-cooling-system__charge-air-cooling-system-draining-and) .
3. Ignition ON, command the CAC Clnt. Pump ON and OFF with a scan tool while observing the following control circuit status parameters: CAC Clnt. Pump Relay Ckt. Short Gnd Test Status CAC Clnt. Pump Relay Ckt. Open Test Status CAC Clnt. Pump Relay Ckt. Short Volts Test Status Each parameter should toggle between OK and Not run or Not Run and OK.

Note. You must perform the Circuit/System Verification before proceeding with the Circuit/System Testing.

1. Ignition OFF, disconnect the INCLR coolant pump relay.
2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 86 and ground. If the test lamp illuminates, test the control circuit for a short to voltage.
3. Verify that a test lamp illuminates between the coil circuit terminal 85 and ground. If the test lamp does not illuminate, test the B+ coil circuit for an open/high resistance. If the circuit tests normal and the B+ circuit fuse is normal, test or replace the intercooler pump relay.
4. Verify that a test lamp illuminates between the B+ switch circuit terminal 30 and ground. If the test lamp does not illuminate, test the B+ switch circuit for an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the voltage output control circuit terminal 87 for a short to ground. If the circuit tests normal, test or replace the intercooler water pump.
5. Disconnect the harness connector at the intercooler water pump.
6. Test for less than 2 ohms between the intercooler water pump ground circuit terminal A and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
7. Connect the harness connector at the intercooler water pump.
8. Connect a 30A fused jumper wire between the B+ switch circuit terminal 30 and the voltage output control circuit terminal 87. Verify that intercooler water pump is activated. If the intercooler water pump does not activate, test the voltage output control circuit for an open/high resistance. If the circuit tests normal, test or replace the intercooler water pump.
9. Verify that a test lamp does not illuminate between the B+ coil circuit terminal 85 and the control circuit terminal 86. If the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.
10. Remove the test lamp.
11. Command the CAC Clnt. Pump ON with a scan tool. Verify the scan tool CAC Clnt. Pump Relay Ckt. Short Volts Test Status parameter is OK. If not the specified value, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.
12. Install a 3A fused jumper wire between the control circuit terminal 86 and the B+ circuit terminal 85. Command the CAC Clnt. Pump ON with a scan tool. Verify the scan tool CAC Clnt. Pump Relay Ckt. Short Volts Test Status is Fault. If not the specified value, test the control circuit for an open/high resistance. If the circuit test normal, replace the ECM.
13. If all circuits test normal, replace the INCLR intercooler pump relay.

Coolant Pump Relay

1. Ignition OFF, disconnect the INCLR coolant pump relay.
2. Test for 135-175 ohms between terminals 85 and 86. If the resistance is not within the specified range, replace the relay.
3. Test for infinite resistance between the following terminals: 30 and 86 30 and 87 30 and 85 85 and 87 If not the specified value, replace the relay.
4. Install a 10A fused jumper wire between relay coil terminal 85 and 12V. Install a jumper wire between relay coil terminal 86 and ground. Test for less than 1.0ohms between switch terminals 30 and 87. If greater than the specified range, replace the relay.

CAC Pump Dynamic Test

1. Install a 30A fused jumper wire between the B+ terminal B and 12V.
2. Install a jumper wire between the ground terminal A and ground.
3. Observe for the CAC pump to activate. If the CAC pump does not activate, replace the CAC coolant pump.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Control Module References»(/cadillac/cts/ii-2007-2014/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
2. «Relay Replacement (Attached to Wire Harness)»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) or «Relay Replacement (Within an Electrical Center)»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
3. «Charge Air Cooler Coolant Pump Replacement»(/cadillac/cts/ii-2007-2014/remont/cooling-system-mechanical/#engine-cooling-system)

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Circuit/System Description

The malfunction indicator lamp (MIL) also known as the service engine soon (SES) or check engine lamp, is located on the instrument cluster. The MIL, when illuminated, informs the driver of an emission system fault, and that service to the system is required. An ignition circuit supplies power to the lamp and the engine control module (ECM) provides a switched ground.

Schematic Reference

1. «Instrument Cluster Schematics»(/cadillac/cts/ii-2007-2014/remont/gauges-instrument-panels/#instrument-panel-system-displays-gauges)
2. «Engine Controls Schematics»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-wiring-schematic-diagrams)

Connector End View Reference

Component Connector End Views

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/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

Note. Any MIL requesting DTCs that may be set should be diagnosed first.

Ignition ON, the MIL should turn ON and OFF when commanded with a scan tool.

1. Ignition OFF, disconnect the harness connector at the P16 instrument cluster.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 20 and ground. If the test lamp does not illuminate, test the 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 P16 instrument cluster.
3. Connect a test lamp between the control circuit terminal 13 and the ignition circuit terminal 20.
4. Command the MIL ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the 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 K20 ECM. 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 K20 ECM.
5. If all circuits test normal, replace the P16 instrument cluster.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM and instrument cluster replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

This Engine Cranks but Does Not Run diagnostic procedure is an organized approach to identify a condition which causes the engine to crank but not start. This diagnostic procedure directs the technician to the appropriate system diagnosis.

Inspect for any of the following conditions

1. The fuel pump control module controls and monitors the operation of the in-tank fuel pump. If the fuel pump control module detects a fault, a DTC sets in the fuel pump control module. The fuel pump control module will then send a serial data message to the engine control module (ECM) requesting the illumination of the malfunction indicator lamp (MIL).
2. Insufficient fuel can cause a no start condition. Thoroughly inspect the fuel delivery system for sufficient fuel volume to the fuel injectors. Inspect the fuel supply components for partial blockage or restrictions.
3. Fuel injectors with partially blocked and restricted nozzles, or a malfunctioning solenoid, can cause a no start condition. Refer to «Fuel Injector Diagnosis (w/J39021 or w/Tech 2)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) or «Fuel Injector Diagnosis (w/CH47976)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .
4. There may be fuel spray at the fuel injectors and the indicated fuel pressure may be correct, yet there may not be enough fuel to start the engine. If the fuel injectors and the injector circuit are OK, and fuel spray is detected, the fuel injector ON time may be inadequate. If the engine control module (ECM) receives incorrect inputs from the various information sensors, the fuel delivered by the fuel injectors may be inadequate to start the engine. Check all the engine data parameters with a scan tool and compare the values indicated with the expected values or the values from a known good vehicle.
5. Inspect the engine for good secure electrical grounds.
6. Water or foreign material in the fuel can cause a no start or engine will not stay running condition. During freezing weather water can freeze inside the fuel system. The engine may start after 30 minutes in a heated repair shop. The malfunction may not recur until parked overnight in freezing temperatures. Extreme weather conditions can cause contaminated fuel to prevent the vehicle from starting.
7. A vehicle that starts and runs after being brought to the repair shop for a no start condition, may have an ignition system that is susceptible to moisture. Spray water on the ignition system components and the wiring in order to check for an engine starting or will not stay running concern.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

1. «Electronic Ignition System Description»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-description-and-operation)
2. «Fuel System Description»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-description-and-operation)
3. «Immobilizer Description and Operation (without Y41)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system__immobilizer-description-and-operation-without-y41) or «Immobilizer Description and Operation (with Y41)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/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. Verify there is adequate fuel in the fuel tank.
2. Ignition ON, test the fuses that are supplied voltage by the powertrain relay. The test lamp should illuminate for each test point of the fuses. If the test lamp does not illuminate for at least one test point of each fuse, refer to «DTC P0685 or P0690»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-dtc-p0685-dtc-p2635) for powertrain relay system diagnosis.
3. Engine cranking, observe the Engine Speed parameter with a scan tool. The reading should show engine speed greater than 175 RPM. If the cranking speed is slow, refer to «Engine Cranks Slowly»(/cadillac/cts/ii-2007-2014/remont/charging-system/#battery-charging-system-and-starting-system) . If engine speed reading is 0 RPM, refer to «DTC P0335»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-dtc-p0230-dtc-p0650) for crankshaft position sensor diagnosis.
4. Ignition ON, observe the ECM, fuel pump control module, and theft deterrent module DTC information with a scan tool. No DTCs should be set. If there are any DTCs set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) for diagnosis.
5. Disconnect the mass airflow (MAF) sensor. Attempt to start the engine. The ECM will ignore MAF sensor input, default to calculated airflow, and the engine should start and run if the MAF sensor is faulted. If the engine starts and runs, and the MAF sensor circuits test OK, replace the MAF sensor.
6. Ignition OFF, inspect the engine air filter, intake duct, and MAF sensor. The air way should be clear. If the intake duct is blocked or collapsed, or the filter is restricted or water saturated, repair or replace as necessary. If the MAF sensor is damaged or contains water, replace it.
7. Ignition ON, observe the Throttle Body Idle Airflow Compensation parameter with a scan tool. The reading should be less than 80%. If the reading is greater than 80%, inspect the throttle body bore for excessive deposits and clean the throttle body. Refer to «Throttle Body Cleaning»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__throttle-body-cleaning) .
8. Observe the BARO parameter with a scan tool. Determine your altitude and compare the BARO reading to the «Altitude Versus Barometric Pressure»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-specifications__altitude-versus-barometric-pressure) table. The reading should be within the range specified. If the reading is not within the specified range in the table, and the barometric pressure sensor circuits test OK, replace the barometric pressure sensor.
9. Perform the «Electronic Ignition System Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) to verify the ignition system provides spark to the cylinders.
10. Ignition OFF, remove and inspect the engine spark plugs. They should be dry. If the spark plugs are coolant fouled, refer to «Coolant in Combustion Chamber»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-diagnostic-information-and-procedures__coolant-in-combustion-chamber) . If the spark plugs are fuel fouled, replace the spark plugs.
11. Collect a fuel sample from the fuel tank. The sample should be bright and clear, free of water, dirt, or other debris. Also, verify the fuel is the correct type for this engine. Refer to «Alcohol/Contaminants-in-Fuel Diagnosis (without Special Tool)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) or «Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) . If the fuel is contaminated with water, dirt, or other debris, replace the fuel filter and refer to «Fuel System Cleaning»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__fuel-system-cleaning) . If the fuel is not the correct type, drain the fuel system and the fuel tank and replace with the correct type.
12. Perform the «Fuel System Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) to verify proper fuel pump operation and fuel pressure.
13. Ignition ON, observe the ECT Sensor parameter with a scan tool. Compare the parameter reading to the actual engine coolant temperature. The readings should be within ±3°C (±5°F). If the temperature readings are not within the ±3°C (±5°F) of each other and the ECT sensor circuits test OK, replace the ECT sensor.
14. Test the engine compression. Refer to «Engine Compression Test»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-diagnostic-information-and-procedures__engine-compression-test) . The compression should be within specification. If engine compression is not within specification, repair the engine as necessary.
15. Inspect the exhaust system. The exhaust system should be free of restrictions. Refer to «Restricted Exhaust»(/cadillac/cts/ii-2007-2014/remont/exhaust/#engine-exhaust-system) . If a restriction or blockage is found, repair the exhaust system as necessary.
16. Ignition OFF, inspect the timing chain and sprockets. They should be properly aligned, free of damage, with minimal wear. Refer to «Camshaft Timing Chain and Sprocket Replacement (LSA)»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-repair-instructions-on-vehicle__camshaft-timing-chain-and-sprocket-replacement) and «Camshaft Timing Chain and Sprocket Cleaning and Inspection»(/cadillac/cts/ii-2007-2014/remont/mechanical/#engine-mechanical-62l-repair-instructions-off-vehicle-1-of-3__camshaft-timing-chain-and-sprocket-cleaning) . If a condition is found, repair the engine as necessary.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Air Cleaner Element Replacement (LSA)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-repair-instructions)
2. «Air Cleaner Resonator Outlet Duct Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)
3. «Spark Plug Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)
4. «Fuel Tank Fuel Pump Module Replacement - Right Side»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions) for fuel filter replacement which is not serviced separately.
5. «Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LSA)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-30l-or-36l-repair-instructions)
6. «Barometric Pressure Sensor Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)
7. «Engine Coolant Temperature Sensor Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)

Poor Fuel Fill Quality

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

The control module enables the appropriate fuel injector pulse for each cylinder. The ignition voltage is supplied directly to the fuel injectors. The control module controls each fuel injector by grounding the control circuit via a solid state device called a driver. A fuel injector coil winding resistance that is too high or too low will affect the engine driveability. A fuel injector control circuit DTC may not set, but a misfire may be apparent. The fuel injector coil windings are affected by temperature. The resistance of the fuel injector coil windings will increase as the temperature of the fuel injector increases.

When performing the fuel injector balance test, the scan tool is first used to energize the fuel pump relay. The fuel injector tester or the scan tool is then used to pulse each injector for a precise amount of time, allowing a measured amount of the fuel to be injected. This causes a drop in the system fuel pressure that can be recorded and used to compare each injector.

1. Monitoring the misfire current counters, or misfire graph, may help to isolate the fuel injector that is causing the condition.
2. Operating the vehicle over a wide temperature range may help isolate the fuel injector that is causing the condition.
3. Perform the fuel injector coil test within the conditions of the customer's concern. A fuel injector condition may only be apparent at a certain temperature, or under certain conditions.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

1. CH-48027 Digital Pressure Gauge
2. J 39021 Fuel Injector Coil and Balance Tester
3. J 44602 Injector Test Adapter

Fuel Injector Coil Test

Verify the resistance of each fuel injector with one of the following methods

1. If the engine coolant temperature (ECT) sensor is between 10-32°C (50-90°F), the resistance of each fuel injector should be 11-14 ohms. If the injectors measure OK, perform the Fuel Injector Balance Test - Fuel Pressure Test. If not within the specified range, replace the fuel injector.
2. If the ECT sensor is not between 10-32°C (50-90°F), measure and record the resistance of each fuel injector with a DMM. Subtract the lowest resistance value from the highest resistance value. The difference between the lowest value and the highest value should be equal to or less than 3 ohms. If the difference is equal to or less than 3 ohms, refer to Fuel Injector Balance Test - Fuel Pressure Test for further diagnosis of the fuel injectors. If the difference is more than 3 ohms, add all of the fuel injector resistance values to obtain a total resistance value. Divide the total resistance value by the number of fuel injectors to obtain an average resistance value. Subtract the lowest individual fuel injector resistance value from the average resistance value. Compute the difference between the highest individual fuel injector resistance value and the average resistance value. Replace the fuel injector that displays the greatest difference above or below the average.

Fuel Injector Balance Test-Fuel Pressure Test

1. Install a CH-48027 . Refer to «Fuel Pressure Gauge Installation and Removal»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions) .
2. Turn ON the ignition, with the engine OFF.
3. Command the fuel pump relay ON with a scan tool.
4. Observe the fuel pressure gauge with the fuel pump commanded ON. The fuel pressure should be 345-414 kPa (50-60 psi). If the fuel pressure is not 345-414 kPa (50-60 psi), refer to «Fuel System Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .
5. Monitor the CH-48027 for one minute. The fuel pressure should not decrease more than 34 kPa (5 psi). If the fuel pressure decreases more than 34 kPa (5 psi), refer to «Fuel System Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .
6. Perform the Fuel Injector Balance Test with Special Tool or the Fuel Injector Balance Test with Tech 2.

Fuel Injector Balance Test with Special Tool

1. Set the amperage supply selector switch on the fuel injector tester to the Balance Test 0.5-2.5 amp position.
2. Connect the J 39021 to a fuel injector with a J 44602 .
3. Command the fuel pump relay ON and then OFF three times with a scan tool. On the last command, as the fuel pressure begins to slowly degrade and stabilize, select a fuel pressure within 34 kPa (5 psi) of the maximum pump pressure. Record this fuel pressure. This is the starting pressure at which you will pulse each injector.
4. Command the fuel pump relay ON one more time and energize the fuel injector by depressing the Push to Start Test button on the J 39021 at the previously selected pressure.
5. After the injector stops pulsing, select Min from the Display Mode and record the Min pressure.
6. Clear the Min/Max results.
7. Select Normal from the Display Mode.
8. Repeat steps 2 and 4 through 7 for each fuel injector.
9. Perform the Pressure Drop Calculation.

Fuel Injector Balance Test with Tech 2

1. Command the fuel pump relay ON and then OFF three times with a scan tool. On the last command, as the fuel pressure begins to slowly degrade and stabilize, select a fuel pressure within 34 kPa (5 psi) of the maximum pump pressure. Record this fuel pressure. This is the starting pressure at which you will pulse each injector.
2. With a scan tool, select the Fuel Injector Balance Test function within the Special Functions menu.
3. Select an injector to be tested.
4. Press Enter to prime the fuel system.
5. Energize the fuel injector by depressing the Pulse Injector button on the scan tool at the previously selected pressure.
6. After the injector stops pulsing, select Min from the Display Mode on the CH-48027 and record the Min pressure.
7. Clear the Min/Max results on the CH-48027 .
8. Select Normal from the Display Mode on the CH-48027 .
9. Press Enter on the scan tool to bring you back to the Select Injector screen.
10. Repeat steps 3 through 9 for each fuel injector.
11. Perform the Pressure Drop Calculation.

Pressure Drop Calculation

1. Subtract the minimum pressure from the starting pressure for one fuel injector. The result is the pressure drop value.
2. Obtain a pressure drop value for each fuel injector.
3. Add all of the individual pressure drop values except for the injector suspected of being faulty. This is the total pressure drop.
4. Divide the total pressure drop by the number of fuel injectors that were added together. This is the average pressure drop. The difference between any individual pressure drop and the average pressure drop should not be more than 20 kPa (3 psi). If the difference between any individual pressure drop and the average pressure drop is more than 20 kPa (3 psi), replace the fuel injector, E-85 only. All other engine, refer to «Fuel Injector Cleaning»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__fuel-injector-cleaning) .

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Fuel Injector Replacement

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

The control module enables the appropriate fuel injector pulse for each cylinder. The ignition voltage is supplied directly to the fuel injectors. The control module controls each fuel injector by grounding the control circuit via a solid state device called a driver. A fuel injector coil winding resistance that is too high or too low will affect the engine driveability. A fuel injector control circuit DTC may not set, but a misfire may be apparent. The fuel injector coil windings are affected by temperature. The resistance of the fuel injector coil windings will increase as the temperature of the fuel injector increases.

The CH-47976 , is used to test the fuel pump, fuel system leak down, and the fuel injectors. Following the User Guide, CH 47976-11, and the on screen prompts or selections, will indicate the steps required to perform each of the available tests. The tester will perform all of the tests automatically and display results of the test. The results can also be down loaded for storage and printing.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Special Tools

CH-47976 Active Fuel Injector Tester

Verify the resistance of each fuel injector with one of the following methods

1. If the engine coolant temperature (ECT) sensor is between 10-32°C (50-90°F), the resistance of each fuel injector should be 11-14 ohms. If the injectors measure OK, perform the Active Fuel Injector Tester (AFIT) Test Procedure. If not within the specified range, replace the fuel injector.
2. If the ECT sensor is not between 10-32°C (50-90°F), measure and record the resistance of each fuel injector with a DMM. Subtract the lowest resistance value from the highest resistance value. The difference between the lowest value and the highest value should be equal to or less than 3 ohms. If the difference is equal to or less than 3 ohms, refer to AFIT Test Procedure. If the difference is more than 3 ohms, add all of the fuel injector resistance values to obtain a total resistance value. Divide the total resistance value by the number of fuel injectors to obtain an average resistance value. Subtract the lowest individual fuel injector resistance value from the average resistance value. Compute the difference between the highest individual fuel injector resistance value and the average resistance value. Replace the fuel injector that displays the greatest difference above or below the average.

AFIT Test Procedure

1. Turn OFF all accessories.
2. Turn OFF the ignition.
3. Install the AFIT. Refer to the AFIT User Guide.
4. Turn ON the AFIT and select the vehicle.
5. Turn ON the ignition and perform the Injector Test. If the AFIT aborts testing due to fuel pressure or fuel leak down, refer to «Fuel System Diagnosis»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .
6. View the test results. If any injector exceeds the recommended tolerance, replace the injector(s), E-85 only. All other engine, refer to «Fuel Injector Cleaning»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__fuel-injector-cleaning) .

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Fuel Injector Replacement

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

Diagnostic Fault Information

The engine control module (ECM) supplies voltage to the fuel pump control module when the ECM detects that the ignition is on. The voltage from the ECM to the fuel pump control module remains active for two seconds, unless the engine is in crank or run. While this voltage is being received, the fuel pump control module closes the ground switch of the fuel pump and also supplies a varying voltage to the fuel tank pump module in order to maintain the desired fuel rail pressure.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Fuel System Description

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the fuel pump ON and OFF using the scan tool ECM output control. The fuel pump should turn on and off.

1. Ignition OFF, disconnect the harness connector at the G12 fuel pump.
2. Connect a test lamp between the control circuit terminal 1 and ground.
3. Ignition ON, command the G12 fuel pump ON and OFF using a scan tool ECM fuel pump output control. The test lamp should turn ON and OFF, as commanded. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K27 fuel pump control module. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K27 fuel pump control module.
4. Ignition OFF, connect a test lamp between the control circuit terminal 1 and the low reference circuit terminal 2.
5. Ignition ON, command the G12 fuel pump ON using a scan tool. The test lamp should illuminate. If the test lamp does not illuminate, test the low reference circuit terminal 1 for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K27 fuel pump control module.
6. If all circuits test normal, replace the G12 fuel pump.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for fuel pump control module replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The control module enables the fuel pump when the ignition switch is turned ON. The control module will disable the fuel pump within 2 seconds unless the control module detects ignition reference pulses. The control module continues to enable the fuel pump as long as ignition reference pulses are detected. The control module disables the fuel pump within 2 seconds if ignition reference pulses cease to be detected and the ignition remains ON.

The fuel system is a returnless on-demand design. The fuel pressure regulator is a part of the primary fuel tank module, eliminating the need for a return pipe from the engine. A returnless fuel system reduces the internal temperature of the fuel tank by not returning hot fuel from the engine to the fuel tank. Reducing the internal temperature of the fuel tank results in lower evaporative emissions.

An electric turbine style fuel pump attaches to the primary fuel tank module inside the fuel tank. The fuel pump supplies high pressure fuel through the fuel filter, past the pressure relief valve, and through the fuel feed pipe to the fuel injection system.

The primary fuel tank module also contains a primary jet pump and a secondary jet pump. Fuel pump flow loss, caused by vapor expulsion in the pump inlet chamber, is diverted to the primary jet pump and the secondary jet pump through a restrictive orifice located on the pump cover. The primary jet pump fills the reservoir of the primary fuel tank module. The secondary jet pump creates a venturi action which causes the fuel to be drawn from the secondary side of the fuel tank, through the fuel transfer pipe, to the primary side of the fuel tank.

1. A vehicle that runs out of fuel above empty may indicate a condition with the siphon jet pump, or transfer lines between the fuel tanks. Inspect for blockage, foreign objects or restrictions in all related hardware.
2. A vehicle that runs out of fuel above empty may be caused by an inaccurate fuel level sender. Inspect the float arm for binding, or obstructions.

Description and Operation

Fuel System Description

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References

Special Tools

1. CH 48027: Fuel Pressure Gauge
2. J 37287: Fuel Line Shut-Off Adapters

1. Ignition OFF, all accessories OFF, install the J 37287: adapters and CH 48027: gauge. Refer to «Fuel Pressure Gauge Installation and Removal»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)
2. Ignition ON, command the fuel pump relay ON with a scan tool. Verify the fuel pressure is between 380-520 kPa (55-76 psi) and remains steady for 5 minutes.

1. Ignition ON, command the fuel pump ON with a scan tool and observe the fuel pressure while the fuel pump is operating. Verify the fuel pressure is between 380-520 kPa (55-76 psi). If the fuel pressure is more than the specified range, replace the fuel pump. If the fuel pressure is less than the specified range, remove the fuel tank and test/inspect for the following: Restricted fuel feed pipe Restricted or plugged fuel filter Restricted or plugged strainer Stuck or binding fuel level float Restricted siphon jet pump Restricted transfer lines between fuel tanks Faulty pressure relief valve Poor connections at the harness connectors and ground circuits of the fuel pump If you find a condition, repair as necessary. If all components test normal, replace the fuel pump.
2. Verify that the fuel pressure does not decrease more than 34 kPa (5 psi) in 1 minute. If the fuel pressure decreases more than the specified value, perform the following procedure: Ignition OFF, relieve the fuel pressure. Refer to «Fuel Pressure Relief (With CH 48027)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions) or «Fuel Pressure Relief (Without CH 48027)»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__fuel-pressure-relief-without-ch-48027) . Install the J 37287: adapters between the fuel feed pipe and the fuel rail. Open the valve on the J 37287: adapters. Bleed the air from the fuel pressure gauge. Close the valve on the J 37287: adapters. Verify that the fuel pressure does not decrease more than 34 kPa (5 psi) in 1 minute. If the fuel pressure remains constant, replace the fuel pump. If the fuel pressure drops, locate and replace the leaking fuel injector.
3. Relieve the fuel pressure to 69 kPa (10 psi). Verify that the fuel pressure does not decrease more than 14 kPa (2 psi) in 5 minutes. If the fuel pressure decreases more than the specified value, replace the fuel pump.
4. Remove the J 37287: adapters and CH 48027: gauge. Refer to «Fuel Pressure Gauge Installation and Removal»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions) .
5. Operate the vehicle within the conditions of the customer concern while monitoring fuel related parameters with a scan tool. If the scan tool parameters indicate a lean condition, test/inspect for the following: Restricted fuel feed pipe Restricted fuel filter Restricted siphon jet pump Restricted transfer lines between fuel tanks Faulty pressure relief valve Poor connections at the harness connectors and ground circuits of the fuel pump If all components test normal and the scan tool parameters indicate a lean condition, replace the fuel pump.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Fuel Tank Fuel Pump Module Replacement - Right Side»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)
2. «Fuel Injection Fuel Rail Assembly Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)
3. «Fuel Injector Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)

Description

Water contamination in the fuel system may cause driveability conditions such as hesitation, stalling, no start, or misfires in one or more cylinders. Water may collect near a single fuel injector at the lowest point in the fuel injection system, and cause a misfire in that cylinder. If the fuel system is contaminated with water, inspect the fuel system components for rust, or deterioration.

Alcohol concentrations of 10 percent or greater in fuel can be detrimental to fuel system components. Alcohol contamination may cause fuel system corrosion, deterioration of rubber components, and subsequent fuel filter restriction. Some types of alcohol are more detrimental to fuel system components than others. Ethanol is commonly used in gasoline, but in concentrations of no more than 10 percent. Some fuels, such as E85, contain a very high percentage of ethanol. Fuel with more than 10 percent ethanol may cause driveability conditions such as hesitation, lack of power, stalling, or no start.

Alcohol in Fuel Testing Procedure

The fuel sample should be drawn from the bottom of the tank so that any water present in the tank will be detected. The sample should be bright and clear. If alcohol contamination is suspected then use the following procedure to test the fuel quality.

1. Using a 100 ml (3.4 oz) specified cylinder with 1 ml (0.03 oz) graduation marks, fill the cylinder with fuel to the 90 ml (3.04 oz) mark.
2. Add 10 ml (0.34 oz) of water in order to bring the total fluid volume to 100 ml (3.4 oz) and install a stopper.
3. Shake the cylinder vigorously for 10-15 seconds.
4. Carefully loosen the stopper in order to release the pressure.
5. Re-install the stopper and shake the cylinder vigorously again for 10-15 seconds.
6. Put the cylinder on a level surface for approximately 5 minutes in order to allow adequate liquid separation.

If alcohol is present in the fuel, the volume of the lower layer, which would now contain both alcohol and water, will be more than 10 ml (0.34 oz). For example, if the volume of the lower layer is increased to 15 ml (0.51 oz), this indicates at least 5 percent alcohol in the fuel. The actual amount of alcohol may be somewhat more because this procedure does not extract all of the alcohol from the fuel.

Particulate Contaminants in Fuel Testing Procedure

The fuel sample should be drawn from the bottom of the tank so that any water present in the tank will be detected. The sample should be bright and clear. If the sample appears cloudy, or contaminated with water, as indicated by a water layer at the bottom of the sample, use the following procedure to diagnose the fuel.

1. Using an approved fuel container, draw approximately 0.5 liter (0.13 gal) of fuel.
2. Place the cylinder on a level surface for approximately 5 minutes in order to allow settling of the particulate contamination.

Particulate contamination will show up in various shapes and colors. Sand will typically be identified by a white or light brown crystals. Rubber will appear as black and irregular particles. If particles are found clean the entire fuel system thoroughly.

Water contamination in the fuel system may cause driveability conditions such as hesitation, stalling, no start, or misfires in one or more cylinders. Water may collect near a single fuel injector at the lowest point in the fuel injection system, and cause a misfire in that cylinder. If the fuel system is contaminated with water, inspect the fuel system components for rust or deterioration.

Ethanol concentrations of greater than 10 percent can cause driveability conditions and fuel system deterioration. Fuel with more than 10 percent ethanol could result in driveability conditions such as hesitation, lack of power, stalling, or no start. Excessive concentrations of ethanol used in vehicles not designed for it may cause fuel system corrosion, deterioration of rubber components, and fuel filter restriction.

Test Procedure

1. Test the fuel composition using J 44175 Fuel Composition Tester and J44175-3 Instruction Manual.
2. Subtract 50 from the reading on the DMM in order to obtain the percentage of alcohol in the fuel sample. Refer to the examples in the Fuel Composition Test Examples table.
3. If the fuel sample contains more than 15 percent ethanol, add fresh, regular gasoline to the vehicle's fuel tank.
4. Test the fuel composition.
5. If testing shows the ethanol percentage is still more than 15 percent, replace the fuel in the vehicle.

Fuel Composition Test Examples

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

This ignition system uses individual ignition module/coil assemblies for each cylinder. The engine control module (ECM) controls the spark events by transmitting the timing pulses on the ignition control (IC) circuits to the individual ignition module/coil assemblies in firing order sequence. Each ignition module/coil has the following circuits

1. Ignition voltage
2. Ground
3. Ignition Control (IC)
4. Low reference

1. Depending on location in the spliced ignition voltage circuit, a slight resistance can cause a misfire or a crank/no start condition. A voltage drop test on the circuit will pinpoint this condition.
2. A slight to moderate resistance on any IC circuit can cause a misfire before DTC P0351-P0358 sets.
3. Extended engine cranking time may foul the spark plugs with excessive fuel.
4. When disconnecting electrical connectors or removing fuses and relays from a fuse block, always inspect both mating electrical terminals for corrosion and terminal tightness.
5. Use the J 35616 for any test that requires probing the underhood fuse block terminals, component wire harness terminals, or the ECM wire harness terminals.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/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

1. J 26792 Spark Plug Tester
2. J 35616-A/BT-8637 Connector Test Adapter Kit

1. Verify that the engine is in good mechanical condition before continuing with this diagnostic.
2. Verify the following conditions: The ignition coils/modules are correctly wired and connected The proper firing order The proper spark plug type The proper spark plug gap and torque The proper ohm values for the spark plug wires Refer to «Ignition System Specifications»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-specifications__ignition-system-specifications) and «Spark Plug Inspection»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions__spark-plug-inspection) .

1. Ignition OFF, disconnect the harness connector at the affected ignition coil/modules.
2. Ignition OFF for 90 seconds, test for less than 5 ohms between the ground circuit terminal A and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Test for less than 5 ohms between the low reference circuit terminal B 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 ECM.
4. Ignition ON, verify that a test lamp illuminates between the ignition voltage circuit terminal D and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
5. Exchange the affected ignition coil/module with the ignition coil/module of a good cylinder.
6. Start the engine and observe the scan tool Misfire Current Cylinder parameters. If the misfire transfers with the suspect ignition coil/module, replace as needed.
7. If the circuits test normal, test or replace the spark plugs.

Use the J 26792 to verify the output of each ignition module/coil.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Engine Control Module Programming and Setup (V8)»(/cadillac/cts/ii-2007-2014/remont/communication-devices/#programming-and-setup-all-systems__engine-control-module-programming-and-setup)
2. «Engine Control Module Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)
3. «Ignition Coil Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)
4. «Spark Plug Replacement»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-repair-instructions)

Operating Instructions for the Evaporative Emission System Tester (EEST)

Vehicle Setup

1. Engine OFF, open the hood. Position a large fan to blow air under the vehicle onto the fuel tank area.
2. Connect the red battery clip from the tester to the positive battery terminal.
3. Connect the black battery clip from the tester to chassis ground.

Flowmeter Test - Leak Detection

1. Open the Nitrogen tank valve and turn the NITROGEN/SMOKE valve on the front control panel to NITROGEN.
2. Connect the hose to the correct test orifice on the bottom front of the tester. For orifice size, refer to the GM Service manual for the vehicle being tested. The vehicle specific information can be found in service procedures for DTCs that relate to evaporative emission (EVAP) system leaks.
3. Press and release the remote switch to activate the tester.
4. Position the sliding red flag on the flowmeter to align with the floating indicator. When the red flag is set, press and release the remote switch to deactivate the tester.
5. Remove the hose from the test orifice and install the hose onto the vehicle. For proper connection location, and the special tool numbers for any adapters that may be required, refer to the service procedures for DTCs that relate to EVAP system leaks.
6. Ignition ON, seal the EVAP system per instructions in the service procedures for DTCs that relate to EVAP system leaks. Most systems can be sealed using a scan tool output control for the EVAP canister vent solenoid valve, other systems require that the vent system be plugged.
7. Press and release the remote switch to activate the nitrogen flow and fill the system.
8. Compare the stable floating indicator position to the red flag. ABOVE the red flag, the result is UNACCEPTABLE, FAIL-Go to Smoke Procedure BELOW the red flag, the result is ACCEPTABLE, PASS-Test complete
9. Press and release the remote switch to deactivate the tester.

Smoke Procedure - Locate the Leak

1. Turn OFF any fans that may cause air movement around or near the vehicle.
2. Connect the nitrogen/smoke hose to the vehicle as directed in the service procedures. Some vehicles require that the nitrogen/smoke hose be connected at the front of the EVAP system at the EVAP service port. An adapter may be necessary. Other vehicles require the connection be made at the rear of the system using an adapter at the fuel fill cap. Consult the service procedures for DTCs that relate to evaporative emission (EVAP) system leaks for vehicle specific instructions regarding connection location and adapters.
3. Open the nitrogen tank valve and turn the NITROGEN/SMOKE valve on the control panel to SMOKE.
4. Press and release the remote switch to activate the tester and inject smoke into the EVAP system.
5. Verify smoke has filled the EVAP system by opening the system opposite the end where smoke is injected. When injecting smoke at the service port, remove the fuel fill cap, or temporarily leave the EVAP canister vent valve open, until smoke is observed. Then close the system and continue testing. If using a special tool fuel fill cap adapter at the filler neck, vent the system at the service port until smoke is observed then close the system to continue with the test.
6. Press and release the remote switch to deactivate the tester.
7. Introduce smoke into the system for an additional 60 seconds. Continue introducing smoke at 15-second intervals, as necessary.
8. Using the a high-intensity white light, inspect the entire EVAP system path, and look for the source of the leak indicated by the exiting smoke. Introduce smoke at 15-second intervals, as needed, until leak source is identified.

The Concern

Ideal circumstances for conducting the EVAP Flowmeter Test require equal temperatures between the nitrogen gas and the vehicle EVAP system. Significant differences in temperature between them can result in a flow or pressure change during testing, causing misleading results. Typically, the Evaporative Emissions System Tester is stored indoors, approximately 21°C (70°F). Vehicles brought in for diagnosis may have an EVAP system at significantly different temperatures -40 to +43°C (-40 to +110°F).

For Example

Note. With no temperature difference between the nitrogen gas and EVAP system, the resulting vehicle EVAP system pressure will remain stable at 13 inches H2O once pressurized, providing no leaks are present.

When the EVAP Flowmeter Tests are performed with significant differences in temperature between the nitrogen gas and the vehicle EVAP system, the following results can occur

1. An increase in flow during the flowmeter test can be caused by a vehicle's warm EVAP system cooling down.
2. A decrease in flow during the flowmeter test can be caused by a vehicle's cool EVAP system warming up.

The Solution

When working on a vehicle with significant temperature differences between the vehicle EVAP system and the nitrogen gas, allow the vehicle EVAP system temperature to stabilize as close as possible to the temperature of the nitrogen gas before conducting the Flowmeter Test.

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Several states require that a vehicle pass on-board diagnostic (OBD) system tests and the inspection/maintenance (I/M) emission inspection in order to renew license plates. This is accomplished by viewing the I/M System Status display on a scan tool. Using a scan tool, the technician can observe the I/M System Status in order to verify that the vehicle meets the criteria that comply with the local area requirements.

Conditions for Updating the I/M System Status

Each system monitor requires at least one, and sometimes several diagnostic tests. The result of each test is reported by a DTC. A system monitor is complete when either all of the DTCs composing the monitor have Run and Passed, or when any one of the DTCs comprising the monitor has illuminated the malfunction indicator lamp (MIL). Once the system monitor is complete, the I/M System Status display will indicate YES in the Completed column.

For example, when the HO2S Heater Status indicates YES, either all of the oxygen sensor heater tests have passed or one of the tests has illuminated the MIL. If the vehicle has 4 heated oxygen sensors, either all 4 heater circuit tests have passed or one of the heater circuit tests has illuminated the MIL. The I/M System Status will indicate NO under the Completed column when any of the required tests for that system have not run. The following is a list of conditions that would set the I/M System Status indicator to NO

1. The vehicle is new from the factory and has not yet been driven through the necessary drive conditions to complete the tests.
2. The battery has been disconnected or discharged below operating voltage.
3. The control module power or ground has been interrupted.
4. The control module has been reprogrammed.
5. The control module DTCs have been cleared.

Monitored Emission Control Systems

The OBD II System monitors all emission control systems that are on-board. The OBD II regulations require monitoring of the following

1. The air conditioning system
2. The catalytic converter efficiency
3. Comprehensive component monitoring-Emission related inputs and outputs
4. The evaporative emission (EVAP) system
5. The fuel delivery system
6. Heated catalyst monitoring
7. Misfire monitoring
8. The oxygen sensor system (O2S or HO2S)
9. The oxygen sensor heater system (HO2S heater)

For the specific DTCs required for each system, refer to Inspection/Maintenance System DTC Table . Systems such as fuel delivery, misfire, and comprehensive components may not be listed in a system status list. These tests run continuously and do not require an I/M System Status indicator.

Review the I/M System Status indicators. All I/M System Status indicators should report YES.

1. Observe the Engine DTC information with a scan tool. If a DTC is set that would prevent the I/M System Status tests from completing, diagnose that DTC before continuing. Refer to «Inspection/Maintenance System DTC Table»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis__inspectionmaintenance-system-dtc-table) .
2. Review applicable service bulletins for software updates that would prevent the I/M System Status tests from completing. If a control module re-program or other repair is required, perform the «Inspection/Maintenance Complete System Set Procedure»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .
3. Observe the I/M System Status indicators. If any I/M System Status indicators report NO, perform the «Inspection/Maintenance Complete System Set Procedure»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) .

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The purpose of the Inspection/Maintenance (I/M) Complete System Set Procedure is to satisfy the enable criteria necessary to execute all of the I/M readiness diagnostics and complete the drive cycles for those particular diagnostics. When all I/M monitored diagnostic tests are completed, the I/M System Status indicators are set to YES. Perform the I/M Complete System Set Procedure if any I/M System Status indicators are set to NO.

I/M Data List

To determine if the I/M readiness diagnostic tests can be run this ignition cycle, use a scan tool to observe the I/M monitor enabled parameters in the I/M Data List.

Conditions for Meeting a Cold Start

1. The ignition voltage between 11-18 volts.
2. The barometric pressure (BARO) is more than 75 kPa.
3. The start-up engine coolant temperature (ECT) is between 4-30°C (39-86°F).
4. The start-up intake air temperature (IAT) is between 4-30°C (39-86°F).
5. The difference between the IAT and the ECT is less than or equal to 6°C (10.8°F).
6. The ambient air temperature is between 4-30°C (39-86°F).
7. The fuel level is between 15-85 percent.

Review the I/M Status indicators with a scan tool. All I/M System Status indicators should report YES.

Inspection/Maintenance (I/M) System Set Procedure

1. Ensure that the vehicle meets the conditions for a cold start listed above.
2. The evaporative emission (EVAP) I/M System Status indicator should display YES. If the EVAP I/M System Status indicator displays NO, perform the EVAP Service Bay Test, if applicable. If the EVAP Service Bay Test is NOT available, it may take up to 6 drive cycles, with up to 17 hours between drive cycles, for the EVAP I/M System Status indicator to transition to YES.
3. The O2S Heater I/M System Status indicator should display YES. If the O2S Heater I/M System Status indicator displays NO, ensure that the ignition has been turned OFF for at least 10 hours.
4. Turn OFF all accessories; HVAC system, other electrical loads, including aftermarket/add-on equipment, etc.
5. Set the vehicle parking brake and ensure the vehicle is in Park for automatic transmission or Neutral for manual transmission.
6. Turn OFF all accessories; HVAC system, other electrical loads, including aftermarket/add-on equipment, etc.
7. Start and idle the engine for at least 2 minutes and until 65°C (149°F) is achieved.
8. Run the engine for 6.5 minutes within the following conditions: MAF parameter between 4-30 g/s Engine speed steady between 1,000-3,000 RPM
9. Return the engine to idle for 1 minute.
10. Apply and hold the brake pedal, and shift to Drive for automatic transmission, or apply the clutch pedal for manual transmission and operate the vehicle within the following conditions for 2 minutes: Depress the accelerator pedal until throttle position (TP) sensor angle is more than 2 percent. Mass air flow (MAF) signal between 15-30 g/s RPM steady between 1,200-2,000 RPM
11. Release the accelerator pedal and shift the vehicle to Park for automatic transmission, or Neutral and release the clutch pedal for manual transmission, and allow the engine to idle for 2 minutes.
12. Quickly depress the accelerator pedal until TP sensor angle is more than 8 percent and return to idle, repeat 3 times.
13. Allow engine to idle for at least 2 minutes.
14. Release the parking brake and drive vehicle at 24 km/h (15 mph) or slower for 2 minutes.
15. Continue to drive the vehicle for at least 5.5 miles between 45-112 km/h (28-70 mph) with the vehicle reaching at least 80 km/h (50 mph).
16. Release the accelerator pedal for at least 2 seconds. This will allow the vehicle to enter decel fuel cut-off.
17. Depress the accelerator pedal until the TP sensor angle is increased 3-20 percent and maintain a safe speed for 1 minute.
18. Safely stop the vehicle, with the engine in Drive for automatic transmission or in Neutral with the clutch pedal depressed and parking brake applied for manual transmission, idle for 2 minutes.
19. Shift to Park for automatic and apply the parking brake, or neutral and release clutch pedal for manual.
20. Turn OFF the ignition and exit the vehicle. Do NOT disturb the vehicle for 60 minutes.
21. Observe the Inspection/Maintenance (I/M) System Status with a scan tool. All of the I/M System Status indicators should display YES. If the EVAP I/M System Status indicator displays NO, turn OFF the ignition for 17 hours, ensure that the vehicle meets the conditions for a cold start, and repeat steps 12-18 six more times, or until the EVAP I/M System Status indicator transitions to YES. If the indicator continues to display NO, refer to the «Inspection/Maintenance System DTC Table»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis__inspectionmaintenance-system-dtc-table) to identify the DTCs that did not run. Follow the Conditions for Running the DTC in order to set the EVAP I/M System Status indicator If any of the I/M System Status indicators display NO, refer to the «Inspection/Maintenance System DTC Table»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis__inspectionmaintenance-system-dtc-table) for the indicator which did not display YES. The I/M System DTC Table identifies the DTCs associated with each I/M System Status Indicator. Follow the Conditions for Running the DTC in order to set the associated status indicator.
22. Observe the engine DTC information with a scan tool. Verify no DTCs are present. If a DTC is set, diagnose using the «Diagnostic Trouble Code (DTC) List - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) . After repairs, perform the «Inspection/Maintenance Complete System Set Procedure»(/cadillac/cts/ii-2007-2014/remont/testing-diagnostics/#engine-controls-and-fuel-62l-symptom-troubleshooting-and-diagnosis) to verify no further DTCs are set.

Inspection/Maintenance System DTC Table

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/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»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The purpose of the evaporative emission (EVAP) Service Bay Test is to aid in resetting the EVAP inspection/maintenance system status. For this vehicle that is equipped with the engine off natural vacuum diagnostic, the Service Bay Test uses the scan tool to initiate the engine control module (ECM) regular sequence of EVAP system DTC tests, but with different enable criteria. By using the Service Bay Test the inspection/maintenance indicator can be set without the need for multiple cold soaks.

The scan tool displays for the Service Bay Test are based on the events that occur within the following three categories

1. The engine running portion of the tests-The vehicle must remain at rest, in Park, or in Neutral, during this portion of the test. This test inspects for large leaks, a leaking purge valve and/or vent system restrictions. The scan tool will display test progress or the reason for an abort or failure.
2. Drive cycle-The scan tool will display time and distance needed to warm the fuel.
3. Ignition OFF-During this portion of the test, the engine controller will remain active for up to 45 minutes when the ignition is turned OFF to allow control of the EVAP canister vent valve and run the engine off natural vacuum test. The engine controller inspects for small leaks during this period by monitoring fuel tank pressure or vacuum. If the system is sealed, there will be a pressure or vacuum change. Pressure or vacuum changes that are less than the calibrated values indicate a leak.

When the EVAP diagnostics are initiated by the Service Bay Test, the scan tool will indicate if the enable conditions listed below are not met, or will display a specific reason if the test aborts. When complete, the display will indicate that the tests passed or failed.

Conditions for Running the Test

The following conditions must be met in order to enable the Service Bay Test

1. The battery voltage is between 11-18V.
2. The engine coolant temperature (ECT) is less than 35°C (95°F) at start-up.
3. The EVAP inspection/maintenance system status indicator is set to NO.
4. The fuel level is 15-85 percent capacity and cannot be refueled during the tests.
5. There are no DTCs displayed.
6. The vehicle must be driven for the time and distance specified on the scan tool.
7. The ambient air temperature is between 0-40°C (32-104°F).
8. The ignition must remain OFF during the engine OFF portion of the test, and the vehicle must remain at rest.

Note. If the Service Bay Test aborts or fails, a DTC will NOT be set.

1. Install a scan tool.
2. Select the Service Bay Test with the scan tool.
3. Follow the instructions on the scan tool. If the test aborts, correct the condition for running the test, then retest. If the test fails, repair the vehicle for the condition indicated by the failure message on the scan tool.
4. Verify that the EVAP inspection/maintenance system status is set to YES.

See also:
• Diagnostic System Check - Vehicle
• Strategy Based Diagnosis
• Control Module References
• Spark Plug Inspection
• Ignition System Specifications
• Coolant in Combustion Chamber
• Oil Consumption Diagnosis
• Torque Converter Diagnosis
• Heated Oxygen and Oxygen Sensor Caution
• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (LSA)
• Symptoms - Engine Exhaust
• Crankcase Ventilation System Inspection/Diagnosis
• Thermostat Diagnosis
• Loss of Coolant
• Symptoms - Engine Mechanical
• Throttle Body Cleaning
• Temperature Versus Resistance - Engine Coolant Temperature Sensor
• ENGINE COOLANT TEMPERATURE SENSOR REPLACEMENT
• Crankshaft and Bearing Cleaning and Inspection
• Symptoms - Engine Electrical
• DTC P0106
• Engine Control Module Scan Tool Information (V8)
• Temperature Versus Resistance
• Engine Overheating (LSA)
• Supercharger Noise Diagnosis
• Evaporative Emission Control System Description
• Fuel System Description
• Diagnostic Procedure Instructions
• Engine Controls Schematics
• Component Connector End Views
• Supercharger Description and Operation
• Supercharger Cleaning and Inspection
• Charge Air Cooling System Coolant Level Inspection
• Diagnostic Repair Verification
• Battery Inspection/Test
• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Electrical Center Identification Views
• Charge Air Cooling System Draining and Filling (Static)
• Relay Replacement (Attached to Wire Harness)
• Charge Air Cooler Coolant Pump Replacement
• Instrument Cluster Schematics
• Immobilizer Description and Operation (without Y41)
• Immobilizer Description and Operation (with Y41)
• DTC P0685 or P0690
• DTC P0335
• Diagnostic Trouble Code (DTC) List - Vehicle
• Altitude Versus Barometric Pressure
• Fuel System Cleaning
• Engine Compression Test
• Restricted Exhaust
• Camshaft Timing Chain and Sprocket Replacement (LSA)
• Camshaft Timing Chain and Sprocket Cleaning and Inspection
• Fuel Injector Cleaning
• Fuel Pressure Relief (Without CH 48027)
• Engine Control Module Programming and Setup (V8)
• Road Test Warning
• Fuel System Diagnosis
• Inspection/Maintenance System DTC Table