P05A7: Active Grille Air Shutter A Supply Voltage Circuit Low

An active grille shutter closes louvres in the grille to cut drag and speed warm-up and opens them for cooling; CARB names it as an off-cycle CO2 technology and treats the actuator as an output component. Smart actuators (Ford 3.0 L diesel, Toyota) check their own coil and supply and report over LIN; simpler ones (VW 1.8 T) have their own supply and a control line from the engine module. GM uses none of P05A2–P05A8. A fault usually only costs fuel and warm-up time. P05A7 means the supply is present but too low. Ford's 3.0 L diesel sets it at once when the actuator measures its internal supply below 6.9 V while system voltage is 9–16.26 V, from 5 s after start – pointing to a voltage drop in feed or ground or an internal actuator fault.

Symptoms

• Check engine light on
• Shutter inoperative at times
• Possibly further voltage codes

Most likely causes

• Contact resistance in connector, wire or ground (corrosion)
• Actuator faulty internally (measuring wrong)
• Weak battery or charging system

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the battery, connectors, and wiring
2. With the connector unplugged, check whether the signal wire is making contact with ground.
3. Read the live data with a scanner
4. Follow the manufacturer's service manual

Good to know

• Repair difficulty: easy
• It affects emissions.

What each character of P05A7 means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• 5: Speed and idle
• A7: Specific fault in that system

Frequently asked questions

Can I keep driving with code P05A7?

If the car is running normally, drive in moderation to a repair shop. If it loses power or another warning appears, do not continue.

What causes code P05A7?

The most common causes are: contact resistance in connector, wire or ground (corrosion); actuator faulty internally (measuring wrong); weak battery or charging system.

Related codes

• P05A6Active Grille Air Shutter A Supply Voltage Circuit/Open
• P05A8Active Grille Air Shutter A Supply Voltage Circuit High
• P0562System Voltage Low
• U0284Lost Communication With Active Grille Air Shutter Module A
• P05B6Active Grille Air Shutter B Supply Voltage Circuit Low

Sources

• fordservicecontent.com: obd summary diesel 2023
• static.nhtsa.gov: MC 10121130 9999

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.