Sensor Power Supply Circuit High Voltage
The P06B5 code indicates that the Engine Control Module (ECM) has detected a voltage higher than the specified range on the 5-volt reference circuit that powers various sensors (e.g., throttle position, manifold absolute pressure, fuel pressure). This can be caused by a short to battery voltage, a faulty sensor, or an internal ECM issue. The high voltage can disrupt sensor readings, leading to drivability problems.
01. Most Common Causes
- Short to battery voltage on the 5V reference circuit
- Faulty sensor (e.g., throttle position sensor, MAP sensor)
- Damaged wiring or connector causing a short
- Internal ECM failure
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine stalling or rough idle
- Poor acceleration or hesitation
- Reduced fuel economy
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm the code and check for additional codes.
Step 2: Visually inspect the wiring and connectors for damage, corrosion, or shorts.
Step 3: Disconnect sensors one by one while monitoring the 5V reference voltage with a multimeter to isolate the short.
Step 4: If voltage remains high with all sensors disconnected, suspect an ECM issue.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the high voltage can cause erratic sensor readings, leading to stalling or poor performance. Have it diagnosed 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 ECM needs replacement.