Circuit/System Verification
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NOTE:
This diagnostic assumes the following:
- The battery is completely charged. Refer to Battery Inspection/Test .
- The engine cranking speed is acceptable. Refer to Engine Cranks Slowly .
- There is adequate fuel in the fuel tank.
- Engine cranking for 15 seconds, observe the DTC information with a scan tool. 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 DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Ignition ON, observe the security indicator. The security indicator should illuminate briefly, and then go out.
- If the security indicator stays ON or is flashing, refer to Diagnostic Trouble Code (DTC) List - Vehicle , , and diagnose any theft deterrent DTCs set as current. For more information concerning the Immobilizer system, refer to Immobilizer Description and Operation .
- Engine cranking, observe the scan tool Engine Speed parameter. The scan tool should indicate an engine speed greater than 0 RPM.
- Test the ignition system for spark-Refer to Electronic Ignition System Diagnosis .
- Ignition ON, command the fuel pump ON with a scan tool. The fuel pump should turn ON for 2-3 s and then turn OFF.
- If the fuel pump does not turn ON, refer to Fuel Pump Electrical Circuit Diagnosis for further diagnosis.
- Ignition OFF, install the CH-48027 . Refer to Fuel Pressure Gauge Installation and Removal .
- The fuel pump may need to be commanded ON several times in order to obtain the highest possible fuel pressure.
- The fuel pressure must be verified while the fuel pump is running.
- Do NOT start the engine for this test.
- Ignition ON, command the fuel pump ON with a scan tool. With the fuel pump running, verify the fuel pressure is between the appropriate value listed below:
- 345-414 kPa (50-60 psi): w/o fuel pump control module:
- 345-690 kPa (50-100 psi): w/ fuel pump control module:
- If not within the specified range, refer to Fuel System Diagnosis (Without FPCM) , Fuel System Diagnosis (FPCM) .
- After the fuel pump turns OFF, verify the pressure does not decrease greater than 34 kPa (5 psi) in 1 minute.
- If not within the specified range, refer to Fuel System Diagnosis (Without FPCM) , Fuel System Diagnosis (FPCM) .
- Verify the following conditions do not 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 P0116 .
- Exhaust system restricted-Refer to Restricted Exhaust .
- Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
- Engine mechanical condition such as worn timing chain and gears or low compression-Refer to Symptoms - Engine Mechanical , or Engine Compression Test .
NOTE:
Additional DTCs may set when using the fuel pump output control.
NOTE:
NOTE:
The fuel pressure must be verified after the fuel pump is turned OFF.