LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Suzuki >> 2006 >> Verona Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC P0221 Through P0459 >> DTC P0300: Engine Misfire Detected >> DTC Troubleshooting
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC Troubleshooting

DTC TROUBLESHOOTING CHART

Step Action Value(s) Yes No
1 Perform an ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK .
Was the check performed?		 - Go to Step 2. Go to ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK .
2
  1. Perform a visual/physical inspection.
  2. Make any repairs that are necessary.

Is the repair complete?		 - Go to Step 26. Go to Step 3.
3 Start the engine and allow it to idle.
Are any current misfire counters incrementing?		 - Go to Step 4. Go to Step 5.
4 Are all counters equal (within a percentage of each other)? - Go to Step 6. Go to Step 10.
5
  1. Turn the ignition ON, with the engine OFF.
  2. Review the Freeze Frame data, and note the parameters.
  3. Operate the vehicle within the Freeze Frame conditions and conditions for setting this DTC as noted.

Are any Misfire Current counters incrementing?		 - Go to Step 4. Go to Diagnostic Aids .
6
  1. Turn the engine OFF.
  2. Install a fuel pressure gauge to the fuel rail.
  3. 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 7. Go to FUEL SYSTEM DIAGNOSIS .
7 Check the fuel for contamination.
Is the fuel OK?		 - Go to Step 8. Go to Step 9.
8 Check for a basic engine problem and repair as necessary.
Is the repair complete?		 - Go to Step 26. -
9 Replace the contaminated fuel.
Is the repair complete?		 - Go to Step 26. -
10
  1. Turn the engine OFF.
  2. Disconnect the fuel injector harness connector.
  3. Crank the engine and check for spark.

Is a spark observed on all 6 spark plugs?		 - Go to Step 11. Go to Step 19.
11 Replace any malfunctioning spark plugs if necessary.
Is the repair complete?		 - Go to Step 26. Go to Step 12.
12
  1. Turn the engine OFF.
  2. Disconnect the fuel injector connectors from the injectors.
  3. Install an injector test light on the injector harness connector for the cylinders that had misfired.
  4. Crank the engine and note the test light.

Does the injector test light blink?		 - Go to Step 13. Go to Step 14.
13 Perform the FUEL INJECTOR BALANCE TEST .
Are the fuel injectors OK?		 - Go to Step 8. Go to Step 15.
14
  1. Disconnect the injector test light.
  2. With a test light connected to ground, probe the ignition feed terminal 1 of the injector harness connector for each cylinder that had misfire.
  3. Crank the engine.

Does the test light illuminate?		 - Go to Step 16. Go to Step 18.
15 Replace any malfunctioning fuel injectors.
Is the repair complete?		 - Go to Step 26. -
16 Check the affected fuel injector driver circuit at terminals K89, K67, K91, K66, K90 and K68 for an open or short to voltage.
Is a problem found?		 - Go to Step 17. Go to Step 23.
17 Repair the open or the shorted fuel injector driver circuit.
Is the repair complete?		 - Go to Step 26. -
18 Repair the open ignition feed circuit between the fuel injector harness connector and the fuel injector connector.
Is the repair complete?		 - Go to Step 26. -
19 Measure the resistance of the spark plugs that the spark plug tester did not spark.
Is the resistance of the spark plug less than the specified value?		 30,000 Ω Go to Step 20. Go to Step 24.
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 cylinders ignition control circuit for an open or short and repair as necessary.
Is the repair complete?		 - Go to Step 26. Go to Step 25.
22 Repair the connector or connections.
Is the repair complete?		 - Go to Step 26. -
23
  1. Turn the ignition OFF.
  2. Replace the ECM.

Is the repair complete?		 - Go to Step 26. -
24 Replace the spark plug cable.
Is the repair complete?		 - Go to Step 26. -
25 Replace the faulty ignition coil.
Is the repair complete?		 - Go to Step 26. Go to Step 23.
26
  1. Using the scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. Operate the vehicle within the conditions for setting this DTC as supported in the text.

Does the scan tool indicate that this diagnostic ran and passed?		 - Go to Step 27. -
27 Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?		 - Go to applicable DTC Table . System OK
scientia non olet · About LEMON Manuals