P232D Cylinder 12 Fuel Injector A Offset Learning At Min Limit

The offset-learning codes for injector A of cylinders 1 to 10 sit at P02CC to P02DF; cylinders 11 and 12 were placed separately at P232B to P232E, and P232D is the lower limit for cylinder 12, the last cylinder of a V12. The engine module calibrates each injector in overrun with small test injections and crankshaft-acceleration feedback (GM: test quantity around 1.5 mm³, values kept per rail pressure level). At the lower bound the injector reaches the expected torque with clearly shorter energizing than nominal – a sign of over-delivery or leakage. CARB counts an exhausted fuel feedback correction as a malfunction. Twelve-cylinder diesels are very rare in OBD-regulated vehicles – Audi sold a V12 TDI Q7 from 2008 to 2012 – and no maker documents P232D publicly; the second injector per cylinder has its own B series from P2C52.

Likely causes

Symptoms

• Check engine light on
• Possibly harsher combustion noise or knocking at idle
• Possibly more smoke or consumption

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: law.cornell.edu, gsi.ext.gm.com, en.wikipedia.org.