Lamp Headlamp High-Beam Circuit Open
The high-beam headlamp circuit has an open connection, meaning electricity cannot flow to illuminate the high beams. It's like a broken light switch that won't complete the circuit to turn on the lights.
The ECU monitors the high-beam headlamp circuit by checking for proper current draw when the high-beam switch is engaged. It detects an open circuit when voltage drop across the lamp load is absent or current falls below the expected threshold, indicating a break in the wiring or lamp connection.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| High-beam circuit current draw | 3-10 amps (depending on lamp type) | Less than 0.5 amps or no measurable current |
| High-beam lamp voltage at switch activation | 11-14 volts | 0 volts or open circuit detected |
Code B1568 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.
Once the fault is repaired, B1568 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.