Faulty internal temperature sensor or circuit inside the control module; Module overheating due to heat soak, poor mounting or restricted cooling or airflow around it; Low or unstable supply voltage or poor earth connections affecting module readings; Corroded or damaged connectors or wiring at the module, for example from water ingress; Faulty or inaccurate coolant or intake air temperature sensor causing the plausibility check to fail; Outdated or faulty module software (model and engine dependent).

P0667

Control Module Internal Temperature Sensor A 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
67: FaultThe specific fault in that area

What it means

P0667 means the powertrain control module (PCM) or another control module has found that its internal temperature sensor 'A' is giving a reading that is out of range or does not make sense. The module compares the internal reading with other data, such as engine coolant temperature, intake air temperature and the time since the engine was switched off. When the value does not plausibly match, or is stuck or changing erratically, the code is set.

Symptoms

Engine warning light on
Usually no noticeable change in driving
Possible poor or erratic running if the module limits some functions
Hard starting or cooling fan behaving oddly in some cases
Other temperature-related codes stored alongside

Possible causes

Faulty internal temperature sensor or circuit inside the control modulelikely
Module overheating due to heat soak, poor mounting or restricted cooling or airflow around itpossible
Low or unstable supply voltage or poor earth connections affecting module readingspossible
Corroded or damaged connectors or wiring at the module, for example from water ingresspossible
Faulty or inaccurate coolant or intake air temperature sensor causing the plausibility check to failpossible
Outdated or faulty module software (model and engine dependent)rare

How to diagnose

Read all stored and pending codes and note the freeze frame data, including engine temperature and battery voltage
Check for related codes, especially coolant, intake air or voltage and communication faults, and deal with those first
Compare live coolant and intake air temperature readings on a cold engine; they should be close to each other and to ambient
Inspect the module, its mounting location and connectors for water ingress, corrosion, heat damage or loose pins
Test battery condition, charging voltage and the main power and earth connections to the module
Check for any signs of excess heat around the module, such as exhaust proximity, missing heat shields or blocked ducting
Check the manufacturer's information for software updates or known faults for this model and engine
Clear the code and road test to see if it returns, then recheck live data

How to fix

Repair or clean damaged wiring, connectors and earth points
Restore correct voltage supply by repairing the charging system or replacing a weak battery
Replace any faulty coolant or intake air temperature sensor that is causing the plausibility fault
Fix the cause of excess heat or water ingress around the module, such as missing shields or ducting
Update the module software if an outdated calibration is a known cause for this vehicle
Repair or replace the control module only after all other causes are ruled out, and have it programmed to the vehicle where required

Can I keep driving?

Low severity

The car can usually be driven normally while you book it in for diagnosis. If it starts running poorly or other warning lights appear, have it checked sooner.

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