B1314: Battery Saver Relay Circuit Open
The B1314 code indicates an open circuit in the battery saver relay coil. This relay cuts power to secondary electrical accessories (like the radio, interior lights, or convenience modules) after a preset time when the ignition is off, preventing excessive battery drain. The Body Control Module (BCM) detects the open circuit when it does not see the expected resistance from the relay coil when it tries to energize it.
1. Commonly Affected Makes
2. Most Common Causes
- Open or defective battery saver relay coil
- Broken or open wiring in the relay control circuit
- Corroded, bent, or loose terminals at the relay connector
- Poor ground connection in the relay control circuit
- Faulty BCM with internal relay driver failure
3. Symptoms You Will Notice
- Battery drains overnight or after short periods
- Accessories like radio or interior lights stay on with ignition off
4. Step-by-Step Diagnosis
Check for battery drain with a multimeter; if excessive, suspect relay stuck closed.
Locate the battery saver relay and test coil resistance; should be within spec (typically 50-200 ohms).
Inspect relay connector for corrosion, damage, or loose pins.
Check for 12V and ground at the relay coil control circuit with ignition off.
If all wiring and relay check out, test BCM output to the relay; replace BCM if faulty.
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, but the battery may drain if the relay fails to open, leaving accessories on. It's best to diagnose and fix promptly to avoid a dead battery.
How much does it cost to fix?▼
Typically $50-$150 for relay replacement, or $200-$600 if wiring repair or BCM replacement is needed.