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.
- If the engine speed is 0 RPM, refer to DTC P0335 , or DTC P0336 for further diagnosis.
Test the ignition system for spark-Refer to Electronic Ignition System Diagnosis .

NOTE:

Additional DTCs may set when using the fuel pump output control.

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 digital pressure gauge. Refer to Fuel Pressure Gauge Installation and Removal .

NOTE:

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) .

NOTE:

The fuel pressure must be verified after the fuel pump is turned OFF.

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 .