DTC Troubleshooting

DTC TROUBLESHOOTING CHART

Step	Action	Value(s)	Yes	No
1	Perform an ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK . Is the system check complete?	-	Go to Step 2.	Go to ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK .
2	Install a scan tool to the Data Link Connector (DLC). Turn the ignition ON, with the engine OFF. Request Diagnostic Trouble Codes (DTCs). Is the DTC P0300 set?	-	Go to applicable DTC Table .	Go to Step 3.
3	Perform a visual/physical inspection. Make any repairs that are necessary. Is the repair complete?	-	Go to Step 25.	Go to Step 4.
4	Start the engine and allow it to idle. Are any current misfire counters incrementing?	-	Go to Step 5.	Go to Step 6.
5	Are all counters equal (within a percentage of each other)?	-	Go to Step 7.	Go to Step 11.
6	Turn the ignition ON, with the engine OFF. Review the Freeze Frame Data, and note the parameters. Operate the vehicle within the Freeze Frame conditions and conditions for setting the DTC as noted. Are any current misfire counters incrementing?	-	Go to Step 5.	Go to Diagnostic Aids .
7	Turn the engine OFF. Install a fuel pressure gauge to the fuel rail. Observe the fuel pressure with the engine running. Is the fuel pressure within the specified value?	284 - 325 kPa (41 - 47 psi)	Go to Step 8.	Go to FUEL SYSTEM DIAGNOSIS .
8	Check the fuel for contamination. Is the fuel OK?	-	Go to Step 9.	Go to Step 10.
9	Check for a basic engine problem and repair as necessary. Is the repair complete?	-	Go to Step 25.	-
10	Replace the contaminated fuel. Is the repair complete?	-	Go to Step 25.	-
11	Turn the engine OFF. Disconnect the fuel injector harness connector. Install a spark tester on cylinder #5. Check the engine for a spark. Is a spark observed?	-	Go to Step 12.	Go to Step 21.
12	Replace the malfunctioning spark plug. Is the repair complete?	-	Go to Step 25.	Go to Step 13.
13	Turn the engine OFF. Disconnect the cylinder #5 fuel injector connector from the injector. Install an injector test light on the injector harness connector terminal 2. Crank the engine and note the test light. Does the injector test light blink?	-	Go to Step 14.	Go to Step 15.
14	Perform the FUEL INJECTOR BALANCE TEST . Are the fuel injectors OK?	-	Go to Step 9.	Go to Step 16.
15	Disconnect the injector test light. With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector. Crank the engine. Does the test light illuminate?	-	Go to Step 17.	Go to Step 19.
16	Replace the malfunctioning fuel injector. Is the repair complete?	-	Go to Step 25.	-
17	Check the affected fuel injector driver circuit for an open or short to voltage. Is a problem found?	-	Go to Step 18.	Go to Step 23.
18	Repair the open or the shorted fuel injector driver circuit. Is the repair complete?	-	Go to Step 25.	-
19	Repair the open ignition feed circuit between the fuel injector harness connector and the fuel injector connector. Is the repair complete?	-	Go to Step 25.	-
20	Inspect the Engine Control Module (ECM) connector and connections. Are the connections OK?	-	Go to Step 21.	Go to Step 22.
21	Check the affected cylinder ignition control circuit for an open or short and repair as needed. Is the repair complete?	-	Go to Step 25.	Go to Step 24.
22	Repair the connector or connections. Is the repair complete?	-	Go to Step 25.	-
23	Turn the ignition OFF. Replace the ECM. Is the repair complete?	-	Go to Step 25.	-
24	Replace the faulty ignition coil. Is the repair complete?	-	Go to Step 25.	Go to Step 23.
25	Using a scan tool, clear the DTCs. Start the engine and idle at normal operating temperature. Operate the vehicle within the conditions for setting the DTC as noted. Does the scan tool indicate that this diagnostic run and pass?	-	Go to Step 26.	Go to Step 2.
26	Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed?	-	Go to applicable DTC Table .	System OK