MANUFACTURER REFERENCE

Generic OBD-II code references — Page 24.

Read the source definition and confirm the exact vehicle, reporting module and diagnostic procedure.

Generic OBD-II

P0665

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.

Intake Manifold Tuning Valve Control Circuit High Bank 2

The transmission control module temperature-sensor circuit

TCM substrate temperature must agree with two other measurements

A very low TCM substrate reading is treated as a circuit fault

An implausibly high substrate reading requires a valid operating context

cylinder 1 glow circuit low and the inrush check

cylinder 1 glow output short toward power

cylinder 2 glow control ground-short monitoring

load-dependent high-voltage fault on glow circuit 2

cylinder 3 glow circuit low versus excessive initial current

cylinder 3 glow circuit high has two load-dependent cases

Ford 7.3L glow-plug control-line fault

cylinder 1 glow-plug open-load diagnosis

open circuit detected on cylinder 2 glow output

cylinder 3 glow circuit appears electrically unloaded

cylinder 4 glow output open-load monitoring conditions

cylinder 5 glow open-load monitor with a source-label conflict

cylinder 6 glow circuit open-load evidence

Cylinder7 glow-plug open monitoring requires an active heating command

Cylinder8 open-load evidence depends on glow heating mode

Touareg V10 cylinder 9 glow-plug circuit

cylinder 4 glow ground-short and inrush-current assessment

cylinder 4 glow-plug high-circuit detection

cylinder 5 glow-plug low circuit and inrush faults

understanding the cylinder 5 glow-plug high fault

cylinder 6 low-circuit detection has a startup branch

cylinder 6 glow-plug output high-circuit fault

Cylinder 10 Glow Plug Circuit/Open

Cylinder 11 Glow Plug Circuit/Open

Cylinder 12 Glow Plug Circuit/Open

Ford glow-plug module communication check

Volkswagen CJAA glow-controller communication fault

powertrain relay open-circuit detection uses the off state

low power-relay control voltage can overlap an open fault

power-relay control high with an unresolved state conflict

J271 load-circuit failure can explain fan or no-start complaints

relay feedback remains low when the relay is on

A relay that de-energizes too early is a timing classification

ECM/PCM Power Relay De-Energized Performance - Too Late

Cylinder7 glow-control low is a short-to-ground classification

Zero current alone cannot distinguish every glow-plug fault

Cylinder8 glow-control low uses a different category from open load

Cylinder8 high-circuit evidence needs the driver’s classification

relay feedback stays high after an off command

cooling-fan relay control is unexpectedly low while off

cooling-fan control stays high during an on command

Fan2 circuit low can include an open relay circuit in this Ford monitor

Fan2 high-control monitoring reports a short-to-power category

Fan relay 3 low-side diagnostic can also indicate an open circuit

Fan relay 3 driver reports a high-circuit condition

reference circuit 3 faults include rapid variation

Reference voltage C is low, but the code does not name the attached sensor

A high five-volt reference needs a supply-level diagnosis

Cylinder 9 Glow Plug Control Circuit Low

Cylinder 9 Glow Plug Control Circuit High

Cylinder 10 Glow Plug Control Circuit Low

Cylinder 10 Glow Plug Control Circuit High

The ECM is forwarding a fuel-controller fault request

Throttle Actuator Control Lamp Control Circuit

Ford variable-displacement A/C diagnosis before compressor replacement

Variable compressor valve control circuit low

Variable compressor valve control circuit high

reference D means the fourth monitored ECM reference

transmission speed-sensor supply 1 undervoltage

Reference D high can be a 10.5-volt speed-sensor supply check

Sensor reference A can invalidate several otherwise unrelated monitors

Sensor reference B is a separate monitored supply group

Sensor reference C needs its own circuit identification

Sensor Reference Voltage D Circuit Range/Performance

Control Module Internal Temperature B Too High

Control Module Internal Temperature Sensor B Circuit

Powerup temperature plausibility depends on two independent differences

A low powerup-temperature signal has load and speed prerequisites

An extreme powerup-temperature reading is a circuit diagnosis

engine shutdown code can reflect controller pattern monitoring

Sensor Power Supply A Circuit/Open

speed-sensor supply switch current or temperature fault

Motor A sensor power is a 15-volt rail in this implementation

Sensor Power Supply B Circuit/Open

Sensor supply B low may originate from a protective switch report