B1316

Battery Saver Relay Coil Circuit Short To Ground

Body Chassis/Safety Battery Management 🟢 Low — Fix at next service ✅ Safe to Drive
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What This Actually Means

In plain language — no jargon

The battery saver relay, which protects your battery from draining, has an internal short circuit to ground. Think of it like a switch that's stuck in the 'on' position due to a damaged wire touching metal.

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Symptoms You May Notice

3 known symptoms for this code
Battery drains rapidly when vehicle is off
Dashboard lights flicker or dim intermittently
Vehicle may not start or starts weakly
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How Your ECU Detects This

Technical sensor logic and voltage thresholds

The ECM monitors the coil circuit resistance and voltage in the battery saver relay control line. It detects when the circuit shorts to ground, creating an abnormally low resistance path. When resistance drops below threshold, the ECM sets this fault code.

Voltage & Parameter Thresholds

ParameterNormal RangeFault Condition
Coil Circuit Resistance 5-15 ohms when energized Less than 2 ohms or zero ohms (short to ground)
Control Voltage 12V when relay armed Below 2V (pulled to ground)
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Diagnostic & DIY Fix Guide

Check these in order — from cheapest to most complex
1
Battery saver relay harness connector
Inspect and reseat the connector at the relay module; corrosion or loose pins often cause false shorts.
2
Wiring harness to battery saver relay
Check for damaged insulation, pinched wires, or contact with metal chassis; repair or re-route as needed.
3
Battery saver relay assembly
Replace the relay if internal coil is shorted and wiring checks out clean.
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When to See a Professional Mechanic

Not all fault codes are safe to DIY

Code B1316 is a low-severity fault. Your vehicle is generally safe to drive to a workshop for diagnosis. However, do not ignore it indefinitely — low-severity codes often indicate developing problems that become expensive if neglected. Book a diagnostic appointment within 2–4 weeks. If you notice any additional symptoms (rough running, power loss, unusual smells), treat it as higher priority.

Safety note: OBD-II codes identify the system or circuit where a fault was detected — they do not always identify the exact failed component. A professional mechanic using live sensor data will diagnose the root cause more accurately than replacing parts based on the code alone.
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How to Clear Code B1316

What happens after you fix the fault

Once the fault is repaired, B1316 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.

The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.

✅ Safe to Clear When
  • Fault has been diagnosed and repaired
  • You want to confirm the repair worked
  • Code appeared after a sensor was cleaned
⚠️ Do Not Clear When
  • Preparing for an emissions/PUC test
  • Root cause is still undiagnosed
  • Check engine light is flashing
Emissions test note: Clearing codes resets OBD readiness monitors. Most vehicles need 50–100 km of mixed driving before monitors complete. Do not clear codes immediately before an emissions or PUC inspection.