Porsche P0621 Generator Lamp L Control Circuit Malfunction

Description

OBD-II Trouble Code Description for P0621 Porsche

Generator Lamp/L Terminal Circuit

What does this mean?

OBD2 Code P0621 Porsche definition:
The Engine Control Module (ECM) or Powertrain Control Module (PCM) uses the generator turn on signal circuit to control the load of the generator on the engine. A high side driver in the ECM/PCM applies a voltage to the voltage regulator. This signals the voltage regulator to turn the field circuit ON and OFF. The ECM/PCM monitors the state of the generator turn on signal circuit. The ECM/PCM should detect low voltage on generator turn on signal circuit when the ignition is ON and the engine is OFF, or when the charging system malfunctions. With the engine running, the ECM/PCM should detect high voltage on the generator turn on signal circuit. The ECM/PCM performs Ignition ON and RUN tests to determine the status of the generator turn on signal circuit.

Symptoms

Possible sumptoms of OBD code P0621 Porsche
– Engine Light ON (or Service Engine Soon Warning Light)

Causes

Possible causes of OBD code P0621 Porsche
– Generator circuit – Generator circuit short to fround – Generator circuit open/high Resistance – Generator circuit short to voltage – Bad generator/alternator – Faulty ECM/PCM The Error code is generally activated on detection of the following conditions: – During the Ignition ON test, the ECM/PCM detects high voltage on the generator turn on signal circuit for 5 seconds. – During the RUN test, the ECM/PCM detects low voltage on the generator turn on signal circuit for 15 seconds.

Possible Solutions

– Replaced alternator/generator

The OBD2 Code Information Be Applicable For Porsche:

2013 Porsche Cayenne,2013 Porsche Boxster S,2013 Porsche Boxster,2013 Porsche 911,2012 Porsche Panamera,2012 Porsche 911,2011 Porsche 911,2010 Porsche Panamera,2010 Porsche Cayenne,2010 Porsche 911 GT3,2009 Porsche 911,2008 Porsche Cayenne,2008 Porsche Boxster,2008 Porsche 911,2007 Porsche Cayman,2007 Porsche Cayman,2007 Porsche Boxster,2007 Porsche Boxster,2007 Porsche 911,2006 Porsche 911,2005 Porsche Boxster S,2005 Porsche Boxster,2005 Porsche 911,2004 Porsche 911,2003 Porsche 911

 

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