P CODE FAMILY

Powertrain code references — Page 9.

Engine, transmission and powertrain diagnostic references. Exact vehicle and module context still matters.

Generic OBD-II

P0321

These are code references, not a list of confirmed faults on every vehicle. Read the source and applicability notes, then match the exact vehicle, year, engine and scan report.

an implausible G28 signal can follow an unrelated no-start

missing G28 speed signal and the connected wiring path

Ignition/Distributor Engine Speed Input Circuit Intermittent

Excessive filtered knock intensity, including false knock

Knock-sensor continuity checked with an internal test signal

A connected knock sensor with too little mechanical vibration

Low knock-sensor bias on either signal or return

High knock-sensor DC bias is different from strong knock

knock-sensor intermittency includes mounting as well as wiring

Knock-sensor C open-load detection uses accumulated evidence

Knock-sensor C performance uses a normalized reference level

knock sensor C low filtered output

high output from the documented knock-sensor 3 circuit

Knock/Combustion Vibration Sensor C Circuit Intermittent

Ram insufficient-torque indications and 6.4 L PCM coordination

Knock sensor B circuit monitoring waits for repeated eligible events

A high knock reference is different from a low circuit fault

Knock sensor B low is based on filtered output

knock sensor B high-circuit sampling

knock sensor 2 intermittency and a source identification caution

Crankshaft pulses missing during cranking or running

Crankshaft synchronization is unstable even when pulses exist

Crank position found and then lost during a drive cycle

Crank tooth-count plausibility in a GM implementation

Crank signal timing can be wrong even when pulses are present

Knock-sensor D circuit evidence needs a channel-label check

knock-sensor D reference-signal plausibility

Knock-sensor D low must be separated from an ambiguous sensor number

knock circuit high with an unresolved sensor label

Knock/Combustion Vibration Sensor D Circuit Intermittent

Noisy crank data can undermine misfire and synchronization evidence

Bank 1 camshaft Sensor A pulses are missing

Bank 1 camshaft Sensor A produces the wrong pulse count

A low intake-cam signal means missing edges as the crank turns

bank-1 intake cam signal stops at a high level

Unexpected intake cam events can trigger an intermittent circuit result

Bank 2 intake cam circuit evaluation depends on engine-event relationships

Bank 2 intake-cam performance checks the signal pattern

bank-2 intake cam signal remains low without new edges

A high bank 2 intake-cam input is diagnosed when edges disappear

Bank 2 intake cam intermittency can be a misplaced event

Unexpected crankshaft position during a hybrid auto-start

Reported crankshaft direction reversals while the engine runs

Ion Sense System Performance

Ignition control feedback fails to match the command

Cylinder 1 ignition-control open feedback during the off state

Cylinder 2 ignition output judged open by its driver

Cylinder 3 ignition-control circuit opening versus a weak spark

Coil D open-circuit interpretation needs the actual driver mapping

Coil E open-load evidence needs the internal driver mapping

ignition-coil circuit code with inconsistent coil lettering

Coil G continuity is monitored with its driver switched off

Coil H circuit diagnosis needs its internal channel mapping

Ignition Coil I Primary Control Circuit/Open

Ignition E Control Signal Circuit/Open

Ignition E Control Signal Circuit Low

Ignition E Control Signal Circuit High

Ignition F Control Signal Circuit/Open

Ignition F Control Signal Circuit Low

Ignition F Control Signal Circuit High

Ford coil J primary-monitor feedback fault

Ignition Coil K Primary Control Circuit/Open

Ignition Coil L Primary Control Circuit/Open

fuel shutoff can be the response to a misfire

DC/AC Converter Control Module Control Circuit Range/Performance

Bank 1 camshaft Sensor B pulse loss in crank-referenced windows

Bank 1 camshaft Sensor B pulse-count plausibility

bank-1 exhaust camshaft signal lost at low level

Bank 1 exhaust-cam high means a missing-edge electrical state

Resolve the bank 1 cam-channel label before diagnosing intermittency

Ignition G Control Signal Circuit/Open

Ignition G Control Signal Circuit Low

Ignition G Control Signal Circuit High

Ignition H Control Signal Circuit/Open

Ignition H Control Signal Circuit Low

Ignition H Control Signal Circuit High

Crankshaft-reference plausibility on the N62TU

Timing Reference High Resolution Signal A Too Many Pulses

Missing crankshaft reference points

The crankshaft reference position becomes erratic