P059F code meaning
Active Grille Air Shutter A Performance/Stuck Off
Powertrain system Generic code P05xx codes Check engine light
What P059F means
The active grille shutter (A = upper or only shutter, B = second) closes louvres to cut drag and speed warm-up and opens them for cooling; CARB names it as an off-cycle CO2 technology and requires its components to be monitored. P059F compares commanded and reached position. GM checks it in two stages – detection, then five clearing attempts – type B, two trips; Ford's 3.0 L diesel at over 6° deviation in operation or 20° when learning fully open. 'Stuck off' means stuck closed at Toyota (failure type 73) and Nissan; GM and Ford use P059F for any deviation. Typical are ice, snow, debris or a bent bracket – a closed shutter can make the engine run hot in traffic.
P059F at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.3 to 2 hours
- Clears after repairAfter a drive cycle
Symptoms of P059F
- Check engine light on
- Shutter not opening: engine temperature rises in traffic, fan running often
- Often after frost, gone after thawing
Common causes of P059F
- Most likelyLouvres blocked by ice, snow or debris
- PossibleBent bracket or bumper part blocking the louvres
- PossibleActuator, gear or shaft faulty (shutter stays closed)
- PossibleLouvres unhooked or rubbing on horn or intake duct
- Less likelyCalibration or software
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Grille shutterGrille shutter actuatorEngine control module
What each part of P059F means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| 9F | The exact fault in that area. |
What to do next
- Note P059F and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P059F
What does P059F mean?
P059F means "Active Grille Air Shutter A Performance/Stuck Off". The active grille shutter (A = upper or only shutter, B = second) closes louvres to cut drag and speed warm-up and opens them for cooling; CARB names it as an off-cycle CO2 technology and requires its components to be monitored. It is a generic code, so it means the same on every make.
Is it safe to drive with P059F?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P059F fail an emissions test?
Yes, it can. P059F is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P059F to fix?
Difficulty: medium. A typical repair takes 0.3 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P059F clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.