Actuator Supply Voltage Circuit Low
The P0658 code indicates that the powertrain control module (PCM) has detected a low voltage condition on the actuator supply voltage circuit. This circuit provides power to various actuators such as throttle actuator, EGR valve, VVT solenoids, etc. A low voltage reading suggests a short to ground, open circuit, or a failing voltage regulator. This can cause erratic operation or failure of the actuators, affecting engine performance and drivability.
1. Most Common Causes
- Short to ground in the actuator supply voltage circuit
- Open circuit or high resistance in the wiring or connectors
- Faulty PCM or internal voltage regulator failure
- Blown fuse or fusible link for the actuator supply circuit
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine performance issues such as hesitation, stalling, or reduced power
- Actuators not functioning properly (e.g., throttle, EGR, VVT)
- Possible limp mode activation
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm the code and check for related codes.
Step 2: Inspect the actuator supply voltage fuse and replace if blown.
Step 3: Visually inspect wiring and connectors for damage, corrosion, or loose connections.
Step 4: Measure voltage at the actuator supply circuit with a multimeter; should be near battery voltage (12.6V) with key on.
Step 5: If voltage is low, isolate the circuit by disconnecting actuators one by one to find the short.
Step 6: If circuit checks out, suspect a faulty PCM and perform further diagnostics or reprogramming.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code as it can cause unpredictable actuator behavior, leading to loss of power or stalling. Have the vehicle diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, but can be higher if the PCM needs replacement or reprogramming.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.