TSB : Circuit/System Verification

Details

NOTE: This diagnostic assumes the following: The battery is completely charged. The engine cranking speed is acceptable. There is adequate fuel in the fuel tank. Crank the engine for up to 15 seconds. Verify that DTC P0117, P0118, P0122, P0123, P0201-P0208, P0222, P0223, P0300-P0308, P0335, P0336, P0351-P0358, P0562, P0563, P0601-P0604, P0606, P0607, P062F, P0633, P0685, P0690, P1631, P1682, or P2610 is not set. If any of the DTCs are set Refer to Diagnostic Trouble Code (DTC) List - Vehicle . If none of the DTCs are set Ignition ON. Verify the security indicator on the instrument cluster illuminates momentarily If the security indicator stays ON or is flashing Review the Diagnostic Trouble Code (DTC) List - Vehicle , for Immobilizer system DTCs. Refer to Immobilizer Description and Operation for additional information. If security indicator does not stay ON and is not flashing Verify the scan tool Engine Speed parameter displays greater than 0 RPM while cranking the engine. If 0 RPM Refer to DTC P0335 or P0336 . If greater than 0 RPM NOTE: Perform the spark test on at least one cylinder of each cylinder bank. An erratic or weak spark is considered a no spark condition. Ignition OFF, disconnect a spark plug wire from a spark plug. Connect a J 26792 HEI Spark Tester between the boot of the spark plug wire and ground. Verify that the spark tester sparks while cranking the engine. If the spark tester does not spark Refer to Electronic Ignition System Diagnosis . If the spark tester sparks Ignition ON. NOTE: The Fuel Pump Enable may need to be commanded On a few times in order to obtain the highest possible fuel pressure. If the engine is too hot, high fuel pressure readings may result due to hot soak fuel boiling. Allow the engine to cool down until the engine coolant temperature is less than 60 °C (150 °F) before verifying fuel pressure. Command the Fuel Pump Enable On several times with a scan tool. Verify the Fuel Pressure Sensor parameter is between 345-690 kPa (50-100 psi) with the fuel pump running. If not within the specified range Refer to Fuel System Diagnosis . If within the specified range NOTE: The fuel pressure may vary slightly when the fuel pump stops operating. After the fuel pump stops operating, the fuel pressure should stabilize and remain constant. Verify that the Fuel Pressure Sensor parameter, after the pump has turned OFF, stabilizes between 500-599 kPa (72-87 psi). If not within the specified range Refer to Fuel System Diagnosis . If within the specified range Verify that the Fuel Pressure Sensor parameter does not decrease greater than 34 kPa (5 psi) in 1 minute. If not within the specified range Refer to Fuel System Diagnosis . If within the specified range Verify none of the conditions listed below exist: Collapsed air intake duct to the throttle body Restricted air filter element Spark plugs for being fouled A skewed manifold absolute pressure (MAP) sensor-Refer to DTC P0106 . A skewed engine coolant temperature (ECT) sensor-Refer to DTC P0117 or P0118 . Exhaust system restricted-Refer to Restricted Exhaust . Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis . Engine mechanical condition-Refer to Symptoms - Engine Mechanical (LS3) , or Engine Compression Test . If a condition exists Repair or replace as necessary. If no condition exists All OK.