Honda service bulletin 09-050

Diagnose and fix Honda P0339, P0302, P0303

Honda has issued a technical service bulletin 09-050 to address Honda P0339, P0302, P0303 misfire codes on the vehicles listed below. The bulletin requires a software update that can only be performed by a scan tool equipped with reprogramming capabilities. This reprogramming can be performed by a Honda dealer or an independent shop that does reprogramming.

Honda vehicles covered by the Honda service bulletin 09-050

2008 Honda Accord — all engines

2009 Accord 4-door L4 engine – From VIN 1HGCP2…9A000001 thru 1HGCP2…9A114315 and From VIN JHMCP2…9C000001 thru JHMCP2…9C017331

2009 Accord 2-door L4 engine – From VIN 1HGCS1…9A000001 thru 1HGCS1…9A015888What the Honda service bulletin 09-050

What causes Honda P0339, P0302, P0303

If you tried to start your Honda with a weak battery, the ECM will see improper engine rotation patterns from the crankshaft positon sensor and set a P0339, P0302, P0303.

P0339: Crankshaft Position (CKP) Sensor Circuit Intermittent Interruption

The crankshaft position (CKP) sensor detects crankshaft position. When the engine starts, the notched disc connected to the crankshaft turns and the magnetic flux in the semiconductor device changes. The changes of magnetic flux are converted into pulsing signals to the engine control module (ECM). The CKP sensor detects injection/ignition timing for each cylinder and engine speed. If an abnormal amount of pulsing signals from the CKP sensor are detected, a malfunction is detected and a trouble code is stored.

P0339 sets if the ECM detects a result of anything other than 58 pulses during intervals between reference pulses for each crank revolution and the condition has been detected at least 30 times.

The trouble code and check engine light will clear if the malfunction does not return in three consecutive trips in which the diagnostic runs.

Fix Honda P0339, P0302, P0303

Honda has issued a software fix to correct the problem. Contact your Honda dealer or an independent shop that has software reprogramming capabilities to have the new software installed. The software installation takes about 15 minutes of technician time plus the cost of the software update (that’s right, car makers charge shops for the software even though it was their screw up).

©, 2017 Rick Muscoplat