Weak or recently disconnected battery, or low voltage during cranking, resetting the control unit's timer; Poor power or earth supply to the control unit (corroded or loose terminals, connectors or fuses); Intermittent wake-up or network signal fault that makes the control unit misjudge how long the car has been off; Outdated or faulty control unit software or calibration where the manufacturer has identified this as a known cause; Charging system fault causing voltage dips or spikes; Internal fault in the control unit's timer or clock circuit.

P02FF

Propulsion System Inactive Timer Performance.

Generic
Powertrain
Generic code
Low severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
2: AreaFuel and air metering (injector circuit)
FF: FaultThe specific fault in that area

What it means

P02FF means the engine or powertrain control unit has judged that its internal timer for how long the propulsion system has been switched off is not performing correctly. This 'inactive' or 'soak' timer is used for cold-start plausibility checks, such as comparing engine and intake temperatures after a long rest, and for some monitor start conditions. The code sets when the timer value does not make sense against other data, or when the timer stops or resets unexpectedly. The exact test and set conditions vary by manufacturer and model.

Symptoms

Engine warning light on
Usually no change in how the car drives
Some self-test monitors may not complete, which can cause a failed emissions test
Other stored codes relating to supply voltage or communication
Possible slightly unusual cold-start behaviour on some models

Possible causes

Weak or recently disconnected battery, or low voltage during cranking, resetting the control unit's timerlikely
Poor power or earth supply to the control unit (corroded or loose terminals, connectors or fuses)likely
Intermittent wake-up or network signal fault that makes the control unit misjudge how long the car has been offpossible
Outdated or faulty control unit software or calibration where the manufacturer has identified this as a known causepossible
Charging system fault causing voltage dips or spikespossible
Internal fault in the control unit's timer or clock circuitrare

How to diagnose

Read all stored and pending codes and note freeze frame data, including battery voltage and engine temperatures at the time of setting
Ask about recent battery disconnection, jump starts, flat batteries or electrical work
Test battery condition and resting voltage, then check cranking voltage and charging output
Inspect battery terminals, main fuses, earth straps and control unit connectors for corrosion, looseness or damage
Check for other codes, especially network communication or supply voltage faults, and diagnose those first
Check the control unit supply, earth and wake-up circuits against the manufacturer's wiring information for the model
Clear the code, then complete a few full drive cycles with proper cold soaks and see whether it returns
Check for manufacturer service information or software updates that apply to this vehicle

How to fix

Recharge or replace the battery if it is weak or failing
Clean and tighten battery terminals and earth connections, and repair any damaged wiring or connectors
Repair the charging system if voltage is unstable
Fix any network or wake-up signal faults found
Update the control unit software or calibration only where the manufacturer lists it as a fix for this code
Repair or replace the control unit as a last resort, once supply and wiring faults are ruled out

Can I keep driving?

Low severity

The car can normally be driven as usual, and it is fine to book it in for diagnosis. Fix it before an emissions test, because incomplete monitors can cause a fail.

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