Page 1121 of 5267
6.PCM
NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.
Were there any problems found?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Replace and program the Powertrain Control Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 1122 of 5267
P0210-FUEL INJECTOR 10 CIRCUIT
For a complete wiring diagramRefer to Section 8W.
Page 1123 of 5267

When Monitored:
With battery voltage greater than 10.4 volts, the auto shutdown relay energized, injector pulse width less than
10ms, and engine speed less than 3000 rpm.
Set Condition:
This trouble code takes .64 to 10.0 seconds to set when no inductive kick is sensed .18ms after injector turn
off, and with no other injectors on.
Possible Causes
(K342) ASD RELAY OUTPUT CIRCUIT
(K116) INJECTOR CONTROL NO.10 CIRCUIT OPEN
(K116) INJECTOR CONTROL NO.10 CIRCUIT SHORTED TO GROUND
FUEL INJECTOR
PCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.ACTIVE DTC
Ignition on, engine not running.
With a scan tool, read DTC.
Is the DTC active at this time?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.(K342) ASD RELAY OUTPUT CIRCUIT
Turn the ignition off.
Disconnect the NO.10 Fuel Injector harness connector.
Ignition on, engine not running.
With the scan tool, actuate the ASD Relay.
Using a 12-volt test light connected to ground, probe the (K342) ASD
Relay Output circuit in the NO.10 Fuel Injector harness connector.
Does the test light illuminate brightly?
Ye s>>
Go To 3
No>>
Repair the excessive resistanceorshorttogroundinthe
(K342) ASD Relay Output circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
Page 1124 of 5267

3.FUEL INJECTOR
Using a 12-volt test light connected to 12-volts, probe the (K116) Injec-
tor Control NO.10 circuit.
With the scan tool, actuate the NO.10 Fuel Injector.
What is the state of the test light during the actuation?
Brightly Blinking.
Replace the Fuel Injector.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
ON Constantly.
Go To 4
OFF Constantly.
Go To 5
4.(K116) INJECTOR CONTROL NO.10 CIRCUIT SHORTED TO GROUND
Turn the ignition off.
Disconnect the PCM harness connector.
Measure the resistance between ground and the (K116) Injector Control
NO.10 circuit in the Injector harness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (K116) Injector Control
NO.10 circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 6
5.(K116) INJECTOR CONTROL NO.10 CIRCUIT OPEN
Turn the ignition off.
Disconnect the PCM harness connector.
Measure the resistance of the (K116) Injector Control NO.10 circuit from
the Fuel Injector harness connector to the PCM harness connector.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 6
No>>
Repair the open in the (K116) Injector Control NO.10 circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
Page 1125 of 5267
6.PCM
NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.
Were there any problems found?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Replace and program the Powertrain Control Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 1126 of 5267

P0300-MULTIPLE CYLINDER MISFIRE
For a complete wiring diagramRefer to Section 8W.
When Monitored:
Any time the engine is running, and the adaptive numerator has been successfully updated.
Set Condition:
When more than a 2% (2.5% LEV) misfire rate is measured during two trips. Above 3000 RPM 1 trip less than
3000 RPM 2 trip. Three good trips to turn off the MIL.
Possible Causes
(K342) ASD RELAY OUTPUT CIRCUIT
INJECTOR CONTROL CIRCUIT
COIL CONTROL CIRCUIT
IGNITION WIRE
SPARK PLUG
IGNITION COIL
FUEL PUMP INLET STRAINER PLUGGED
RESTRICTED FUEL SUPPLY LINE
FUEL PUMP MODULE
FUEL PRESSURE LEAK DOWN
FUEL INJECTOR
ENGINE MECHANICAL
PCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.CYLINDER MIS-FIRE CONDITION ACTIVE
NOTE: Check for any TSB’s that apply to a Misfire condition. Review the vehicle repair history for any mis-
fire condition repairs that have been performed.
Star the engine.
Observe the WHICH CYLINDER IS MISFIRING screen for at least one minute on the scan tool.
Is there a misfire present?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.VISUAL INSPECTION
NOTE: Anything that affects the speed of the crankshaft can cause a misfireDTC.
NOTE: When a Misfire is detected for a particular cylinder, the PCM will shut down that cylinders Injector
Control circuit.
- Visually inspect the engine for any of the following conditions.
- Worn serpentine belt
- Binding Engine-Driven accessories: A/C Compressor, P/S Pump, Water pump.
- Misalignment of the Water pump, P/S Pump and A/C Compressor pulleys
- Corroded PCM power and ground circuits.
- Improper CKP, CMP, MAP, and TP Sensor mounting
- Poor connector/terminal to component connection. i.e., CKP sensor, Fuel Injector, Ign coil, etc.
Page 1127 of 5267

- Vacuum leaks
- Restricted Air Induction system or Exhaust system.
- Internal engine component failures.
Were any of the above conditions present?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 3
3.(K342) ASD RELAY OUTPUT CIRCUIT
Turn the ignition off.
Disconnect the Ignition Coil harness connector of the misfiring cylinders.
Disconnect the Fuel Injector harness connector of the misfiring cylinders.
Ignition on, engine not running.
With a scan tool, actuate the ASD.
Using a 12-volt test light connected to ground, probe the (K342) ASD Outputcircuit in the Ignition Coil harness
connector and Fuel Injector harness connector while the relay is actuating.
Does the test light illuminate brightly?
Ye s>>
Go To 4
No>>
Repair the excessive resistance or short to ground in the (K342) ASD Relay Output circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
4.IGNITION SYSTEM OPERATION
Turn the ignition off.
Connect the Ignition Coil harness connectors.
Remove the Ignition Coils.
Leave the Fuel Injector harness connector of the cylinder being tested disconnected.
Install a spark tester on the Ignition Coil.
While cranking the engine observe the spark coming from the spark tester.
NOTE: A crisp blue spark that is able tojump the gap of the spark tester should be generated.
Is good spark present?
Ye s>>
Go To 5
No>>
Go To 14
NOTE: Connect the Fuel Injector harness connector before continuing.
5.SPARK PLUG
Turn the ignition off.
Remove the Spark Plug.
Inspect the Spark Plug for the following conditions.
-Cracks
- Carbon Tracking
- Foreign Material
- Gap size out of specifications
- Loose or broke electrode
Page 1128 of 5267

NOTE: Lightly tap the bottom of the spark plug on a solid surface. The electrode in the spark plug should
not move.
Does the Spark Plug have any problems?
Ye s>>
Replace the Spark Plug.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 6
6.FUEL PRESSURE CHECK
WARNING: The fuel system is under a constant pressure (even with the engineoff). Before testing or ser-
vicing any fuel system hose, fitting or line, the fuel system pressure mustbe released. Failure to follow
these instructions can result in personal injury or death.
Install a fuel pressure gauge to the fuel rail.
Start the engine and observe the fuel pressure reading.
NOTE: Fuel pressure specification is 407 KPa +/- 34 KPa (59 psi +/- 5 psi).
Choose a conclusion that best matches your fuel pressure reading.
Within Specification
Go To 7
Below Specification
Go To 12
Above Specification
Replace the fuel filter/pressure regulator.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
7.FUEL PRESSURE LEAK DOWN
NOTE: Before continuing visually and physically inspect the fuel delivery system for external leaks or dam-
age. Repair / replace as necessary.
Turn the ignition off.
WARNING: The fuel system is under a constant pressure (even with the engineoff). Before testing or ser-
vicing any fuel system hose, fitting or line, the fuel system pressure mustbe released. Failure to follow
these instructions can result in personal injury or death
Installspecialtool6539(5/16
)or6631(3/8) fuel line adapter.
Install the fuel pressure gauge.
Start the engine and allow the fuel system to reach maximum pressure.
Turn the ignition off.
NOTE: Fuel specification is 407 KPa +/- 34 KPa (59 psi +/- 5 psi).
Using special tool C4390, Hose Clamp Pliers, pinch the rubber fuel line between the fuel pressure gauge and the
engine.
Monitor the fuel pressure gauge for a minimum of 5 minutes.
NOTE: The pressure should not fall below 241 KPa (35 psi)
Does the pressure fall below the listed specification?
Ye s>>
Replace the leaking Fuel Injector(s).
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 8