High Voltage Service Disconnect Circuit High
The P0B36 code indicates that the high voltage service disconnect circuit voltage is higher than expected. This circuit is part of the high voltage interlock loop, which ensures safety by disabling high voltage components when the service disconnect plug is removed. A high voltage condition can be caused by a faulty service disconnect switch, wiring issues, or a problem with the hybrid battery control module. This code is typically found in hybrid and electric vehicles.
1. Symptoms You Will Notice
- Hybrid system warning light illuminated
- Vehicle may not start or enter high voltage mode
2. Most Common Causes
- Short to battery positive in the service disconnect circuit wiring
- Faulty or damaged service disconnect switch
- Corroded or loose connector/terminal in the monitoring circuit
- Internal failure in the hybrid/EV powertrain control module
- Excessive resistance in the reference ground circuit
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to retrieve all codes and freeze frame data.
Step 2: Visually inspect the service disconnect plug and wiring for damage or corrosion.
Step 3: Test the service disconnect switch circuit for voltage and continuity using a multimeter.
Step 4: Check for technical service bulletins related to P0B36 for your vehicle.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not safe to drive. The high voltage system may be compromised, posing a risk of electric shock or component damage. Have the vehicle towed to a qualified technician.
How much does it cost to fix?▼
The cost typically ranges from $150 to $400, depending on the cause and labor rates. Replacing the service disconnect switch or repairing wiring is usually less expensive than replacing the battery control module.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.