Glow plug for cylinder 11 ageing or partly failed, with resistance outside the normal range; Corroded, loose or damaged connector or terminal at the glow plug or control module; Damaged wiring to cylinder 11 glow plug, such as high resistance, chafing or a partial short; Low battery voltage or a poor earth or supply connection affecting glow plug current; Faulty glow plug control module or driver output; Outdated or faulty control unit software where the manufacturer has issued a correction for this fault.

P06C3

Cylinder 11 Glow Plug Circuit Range/Performance.

Generic
Powertrain
Generic code
Low severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
6: AreaComputer and output circuits
C3: FaultThe specific fault in that area

What it means

P06C3 is a generic code meaning the engine control unit has detected that the glow plug circuit for cylinder 11 is operating outside its expected range or performance. The control unit monitors current draw, voltage or feedback from the glow plug driver, and the reading did not match what it expected for that circuit. This code only applies to engines with at least 11 cylinders, and the exact circuit layout and monitoring method depend on the vehicle and engine.

Symptoms

Malfunction indicator or glow plug warning lamp on
Harder starting when the engine is cold
Rough running or white smoke for a short time after a cold start
Increased cold-start emissions or diesel knock until warmed up
Other glow plug circuit codes stored alongside it

Possible causes

Glow plug for cylinder 11 ageing or partly failed, with resistance outside the normal rangelikely
Corroded, loose or damaged connector or terminal at the glow plug or control modulelikely
Damaged wiring to cylinder 11 glow plug, such as high resistance, chafing or a partial shortpossible
Low battery voltage or a poor earth or supply connection affecting glow plug currentpossible
Faulty glow plug control module or driver outputpossible
Outdated or faulty control unit software where the manufacturer has issued a correction for this faultrare

How to diagnose

Read all stored codes and freeze frame data, noting engine temperature, battery voltage and whether other glow plug codes are present
Check battery condition and charging voltage, as low voltage can upset glow plug circuit monitoring
Visually inspect the cylinder 11 glow plug connector, wiring and the control module connector for damage, corrosion, heat damage or water ingress
Check the relevant fuses and the power and earth connections for the glow plug system, following the vehicle wiring diagram
Measure the cylinder 11 glow plug resistance and compare it with the manufacturer specification for that engine
Check the supply voltage and wiring continuity between the control module and the glow plug, and test for shorts to earth or supply
Use a scan tool to activate the glow plug circuit if supported and check the commanded and actual current or feedback
Check for applicable software updates or technical bulletins for the engine concerned

How to fix

Replace the cylinder 11 glow plug if it is out of specification, and consider the others if they are of similar age
Clean or repair the connector terminals, or replace the connector if it is corroded or damaged
Repair or replace damaged wiring between the control module and the glow plug
Restore sound battery, power and earth connections, and charge or replace the battery if it is weak
Replace the glow plug control module if it is confirmed faulty after the wiring and plug have been proven good
Apply a manufacturer software update only if a known fault in the calibration is confirmed for the vehicle

Can I keep driving?

Low severity

The car can normally be driven and booked in for repair, though cold starting may be poorer in cold weather. Have it fixed soon, as a failed glow plug or wiring fault can get worse or leave you with starting problems.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.