High Voltage Service Disconnect Circuit Malfunction
The P0B33 code indicates a fault in the high voltage service disconnect circuit, which is a safety feature that isolates the high voltage battery pack during maintenance. This circuit includes the service disconnect plug, wiring, and associated sensors. When the powertrain control module detects an open, short, or unexpected voltage in this circuit, it sets the code. This can prevent the vehicle from starting or entering ready mode, and may disable the high voltage system for safety.
01. Most Common Causes
- Faulty high voltage service disconnect plug
- Damaged wiring or connectors in the service disconnect circuit
- Corrosion or loose connections at the service disconnect switch
02. Symptoms You Will Notice
- Vehicle may not start or enter ready mode
- Warning lights on the dashboard (e.g., check hybrid system)
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to read the code and check for related codes.
Step 2: Visually inspect the service disconnect plug and wiring for damage or corrosion.
Step 3: Test the service disconnect switch continuity with a multimeter.
Step 4: Check for open or short circuits in the wiring harness between the switch and the hybrid control module.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not safe. The high voltage system may be disabled, and the vehicle may not operate. Attempting to drive could cause unexpected shutdown or safety hazards.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, depending on the cause. Replacing a faulty service disconnect plug or repairing wiring is usually inexpensive.