What does it mean?
B1626 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Lamp Keypad Output Short Circuit to Ground .
Symptoms
- Keypad illumination stays on permanently, or never lights at all
- Lighting fuse blows repeatedly
- Parasitic drain flattens the battery over a few days of parking
- The keypad may stop responding to code entry as well
- The code sets again immediately after being cleared, without touching anything
Likely causes
- Keypad lamp output wire chafed against door sheet metal or the window regulator
- Water inside the door bridging the keypad connector to ground
- Keypad illumination LED or its internal driver shorted
- Bent connector terminal touching a ground pin
- Harness damage from a previous speaker or door trim installation
- Module output driver damaged by the short and now holding the circuit low
- Corroded splice in the door lighting circuit
How to fix it
- Unplug the keypad and see whether the code stops setting, which separates the keypad from the harness in one step
- With the keypad unplugged, ohm the output wire to ground; a very low reading confirms the short is in the wiring
- Inspect the loom in the door hinge boot and where it passes the window regulator, the two most common chafe points
- Check the door vapour barrier and the drain holes, since water in the door is usually the root cause
- Repair and insulate the wire, re-routing it clear of the regulator and sharp metal
- Replace the keypad if it measures shorted internally with the harness disconnected
- Only after the circuit is proven clean, check the module output, because a fresh module will fail again on a shorted circuit