Diagnostic Instructions
DTC Descriptor
DTC P050B: Ignition Timing Performance
Circuit/System Description
The engine control module (ECM) continuously compares the commanded spark timing to the actual spark timing. The ECM uses the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor in order to calculate the actual spark timing.
Conditions for Running the DTC
• | DTCs P0300, P0301, P0302, P0303, P0304, P0335, P0336, P0351, P0352, P0353, and P0354 are not set. |
• | The engine is operating. |
• | The engine speed is steady. |
• | The ignition voltage is between 11-16 volts. |
• | The DTC runs continuously once the above conditions are met. |
Conditions for Setting the DTC
• | The ECM detects the difference between the actual spark and the commanded spark is greater than 5 degrees. |
• | The condition exists for more than 7 seconds. |
Action Taken When the DTC Sets
DTC P050B is a Type B DTC.
Conditions for Clearing the DTC
DTC P050B is a Type B DTC.
Reference Information
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Circuit/System Testing
- Engine idling, observe the DTC information with a scan tool. Verify that DTCs P0016, P0324, P0325, or P0340 do not fail this ignition cycle.
- Observe the DTC information with a scan tool. Verify that DTC P050B does not set this ignition cycle.
⇒ | If DTC P050B set this ignition cycle replace the ECM. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
Control Module References
for ECM replacement, setup, and programming