LED #1 Circuit Short to Battery
An LED circuit is receiving too much electrical power directly from the battery instead of being controlled properly. It's like a light switch that's stuck in the ON position because the wire is touching the positive battery terminal.
The ECU monitors the voltage and current draw of LED #1 circuit by commanding it on and off and measuring the response. When the circuit shorts directly to battery voltage instead of being pulled low by the ECU's driver transistor, the ECU detects an abnormally high voltage that matches battery potential.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| LED Circuit Voltage | 0-5V (controlled switching) | 12V+ (shorted to battery) |
| LED Current Draw | 50-500mA (circuit active) | Exceeds maximum when shorted |
Code B2373 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, B2373 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.