P05B7

Code

Generic P — Powertrain

Active Grille Air Shutter B Supply Voltage Circuit High

Brand: Generic

Type: P — Powertrain

Views: UK: 23 EN: 36 RU: 23

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Short to battery voltage on the shutter B power feed
Faulty grille shutter B actuator internal failure
Corroded, damaged, or loose connector or wiring (power or reference)
Incorrect or intermittent battery/charging system voltage (overcharging)
Faulty PCM or module reporting incorrect voltage

Symptoms

Malfunction Indicator Lamp (MIL) or DTC warning present
Active grille shutter B stuck open or closed or not responding
Reduced aerodynamic efficiency / possible minor fuel-economy impact
Cooling or HVAC performance may be affected under some conditions
Stored related fault codes in powertrain or body control modules

What to check

Read and record freeze-frame, stored data and ALL related codes
Measure battery voltage with engine off and running (verify charging system)
Visually inspect wiring, harness, and connector for shutter B for damage/corrosion
Check fuses and relays in the shutter/engine compartment power feed
Backprobe actuator B connector and measure supply, ground and signal voltages
Wiggle-test harness while observing voltage/continuity to look for intermittent faults

Signal parameters

Normal system battery voltage: ~11–14.5 V (engine off/running varies)
Expected supply to shutter actuator: battery voltage (approx 12–14.5 V) when power is applied
High-voltage fault when supply significantly above normal operating range or above module-specified threshold (varies by manufacturer)
Ground continuity should be near 0 Ω; supply should not show short to constant battery when circuit is expected switched

Diagnostic algorithm

Retrieve freeze-frame and related codes; note operating conditions when code set.
Verify battery and charging system voltage at the battery with engine off and running. If overcharging (>15 V), diagnose charging system first.
Visually inspect the shutter B connector and wiring for damage, pin push-out, corrosion, melted insulation or repair patches.
With connector disconnected, measure resistance/continuity from the PCM/control module output to the actuator connector. Check for short to battery on the supply circuit (supply showing battery voltage when circuit should be off).
With connector backprobbed and key ON (engine off), measure supply voltage at the actuator power pin and verify ground continuity. Compare to expected battery voltage and module data.
If supply is high only at the actuator connector, isolate and repair harness short to constant battery or replace damaged wiring/connector.
If wiring and supply are normal, bench-test or swap the shutter actuator B (if interchangeable) to confirm actuator failure.
If actuator and wiring check OK, use manufacturer procedures to test/replace the PCM or body control module as a last step.
After repairs, clear codes and perform functional test cycles to confirm proper operation and that the DTC does not return.

Likely causes

Wiring short to constant battery voltage on the shutter B supply conductor
Damaged connector pin at the shutter B actuator (corrosion, bent pin)
Failed actuator with internal shorted electronics
Alternator overcharging causing system voltage above normal limits
Intermittent or poor ground at actuator or control module

Fault status

⚠️ Status

Active Grille Air Shutter B supply voltage is higher than the allowed threshold. PCM flagged an over-voltage condition and may disable control of the B shutter until fault is resolved.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-2.5 hours