Lamp Keypad Output Short Circuit To Ground
The lamp keypad circuit has a short to ground, meaning the wiring or button is allowing electricity to escape to the vehicle's chassis instead of flowing normally. It's like a water pipe with a hole in it—the current leaks out where it shouldn't.
The ECU monitors the voltage output of the lamp keypad circuit, expecting a normal operating voltage range when the button is pressed or released. When a short to ground occurs, the voltage drops abnormally low or to zero, triggering the fault. The ECU detects this voltage deviation beyond acceptable thresholds and stores the code.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Keypad Output Voltage | 5-12V depending on circuit design | Below 0.5V or shorted to ground |
| Circuit Resistance | Expected load impedance | Near 0 ohms indicating direct ground short |
Code B1626 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, B1626 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.