All Body Electrical DTC Codes — Complete OBD-II Diagnostic Guide (2026)
This comprehensive reference covers every Body Electrical diagnostic trouble code (DTC) — 2 codes total. Each code includes what triggers it, common symptoms, step-by-step diagnostic procedures, and repair guidance.
Detailed DTC Code Guides
B1318: The B1318 code tells the vehicle’s body control module that the on‑board battery voltage is below the safe operating threshold. This usually means the battery, alternator, or wiring isn’t delivering enough voltage for the vehicle’s electrical accessories.
Learn what B1318 means, why your battery voltage is low, and how to fix it. Quick DIY steps, cost estimates, and make‑specific tips for Toyota, Honda, Ford,...
- Verify Battery Connections
- Check Battery Voltage with Scan Tool
- Test Alternator Output
- ...see all 5 steps →
B1325: B1325 signals that the on‑board battery voltage is outside the calibrated range (too high or too low). The condition usually points to a weak battery, a slipping alternator belt, a failing alternator, or a defective voltage regulator.
Step‑by‑step instructions for fixing the B1325 code. Learn how to test battery voltage, inspect wiring, and verify the alternator and voltage regulator on...
- Measure Battery Voltage
- Inspect Battery Terminals & Cables
- Check Alternator Belt Condition
- ...see all 5 steps →
Understanding Body Electrical Codes
Body Electrical diagnostic trouble codes are set by your vehicle's onboard computer (ECU/PCM) when it detects a problem in the electrical system. Here's what you need to know:
- How codes are triggered: Sensors monitor electrical performance. When readings fall outside expected ranges, the ECU stores a DTC and illuminates the check engine light.
- Freeze frame data: When a code is set, the ECU also records engine conditions at that moment. This data helps pinpoint the exact cause.
- Pending vs. confirmed: A code becomes "confirmed" after multiple drive cycles with the same fault. Pending codes may clear on their own.
Tools You'll Need for Diagnosis
- OBD-II scanner — Essential for reading and clearing codes. A basic scanner works for most codes.
- Digital multimeter — For testing sensor voltages, resistance, and continuity.
- Repair manual — Vehicle-specific wiring diagrams and specifications.
- Safety equipment — Gloves, safety glasses, jack stands for under-vehicle work.
When to See a Mechanic
While many electrical codes can be diagnosed at home, see a professional if:
- The code is critical severity — driving may cause further damage
- Multiple related codes are present — suggests a deeper systemic issue
- You don't have the tools or experience for the required diagnostic steps
- The repair involves fuel system, exhaust, or catalytic converter work