2010 Cadillac CTS Sedan AWD V6-3.6L Page 1295
1. Install any components or connectors that have been removed or replaced during diagnosis.
2. Perform any adjustment, programming, or setup procedures that are required when a component or module is removed or replaced.
3. Clear the DTCs.
4. Turn OFF the ignition for 60 s.
5. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in
order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle
(See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) and perform the appropriate diagnostic
procedure.
6. To verify that the performance of the catalytic converter has not been affected by the condition that set this DTC, perform the Repair
Verification for DTC P0420 or P0430. Refer to DTC P0420 or P0430 (See: P Code Charts/P0420).
P0303
DTC P0300-P0306 (w/LLT)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0300
- Engine Misfire Detected
DTC P0301
- Cylinder 1 Misfire Detected
DTC P0302
- Cylinder 2 Misfire Detected
DTC P0303
- Cylinder 3 Misfire Detected
DTC P0304
- Cylinder 4 Misfire Detected
DTC P0305
- Cylinder 5 Misfire Detected
DTC P0306
- Cylinder 6 Misfire Detected
Circuit/System Description
The engine control module (ECM) uses information from the crankshaft position sensor and the camshaft position sensors in order to determine
when an engine misfire is occurring. By monitoring variations in the crankshaft rotation speed for each cylinder, the ECM is able to detect
individual misfire events. A misfire rate that is high enough can cause 3-way catalytic converter damage. The malfunction indicator lamp (MIL)
will flash ON and OFF when the conditions for catalytic converter damage are present. DTCs P0301 through P0306 correspond to cylinders 1
through 6. If the ECM is able to determine that a specific cylinder is misfiring, the DTC for that cylinder will set, and the corresponding fuel
injector is disabled. The ECM will re-enable the fuel injector after 4 crankshaft revolutions when the misfire is not current. The ECM will re-enable
the fuel injector after 8 crankshaft revolutions when the misfire is not current, if the vehicle is equipped with a manual transmission.
Conditions for Running the DTC
* DTC P0121, P0122, P0123, P0221, P0222, P0223, P0335, P0336, P0338, or P0461-P0463 is not set.
* The engine speed is between 400-7,000 RPM and steady.
* The evaporative emissions (EVAP) leak detection is not active.
* The delivered torque signal is greater than 5 % at idle.
* The delivered torque signal is between 6-29 % with the transmission in drive.
* The intake air temperature (IAT) is warmer than -30掳C (-22掳F).
* The fuel level is greater than 11 %.
* The ECM is not in fuel cut-off or decel fuel cut-off mode.
* The increase in engine speed is less than 2,500-4,600 RPM/second.
* DTCs P0300 through P0306 run continuously when the above conditions exist for greater than 1,000 engine revolutions. 200 revolutions
