Independent guide · Not a government site
W4-3 warns that another roadway joins ahead with its own added lane.
MUTCD code W4-3 · Warning sign · Source: MUTCD 11th Edition, Section 2C.46
Another road joins with its own lane
Traffic joining the road gets its own lane, so it does not need to merge into yours at that point.
Source: Manual on Uniform Traffic Control Devices, 11th Edition, Section 2C.46; Tennessee Comprehensive Driver License Manual, Section B, Chapter 5, Interstate Driving: Entering the Interstate (p. 68)
Turn
Curve
Cross Road
Stop Ahead
Yield Ahead
Signal Ahead
Merge
Lane Ends
Divided Highway
Slippery When Wet
Grade Crossing Advance Warning
Pedestrian Crossing
Bicycle
No Passing Zone
Road Work
Reverse Turn
Reverse Curve
Winding Road
One-Direction Large Arrow
Chevron Alignment
Large Animals (deer)
Large Animals (cattle)
Farm Vehicle
Emergency Vehicle
Double Arrow
Low Clearance
Dead End
No Outlet
Side Road
T Intersection
Y Intersection
Circular Intersection
Road Narrows
Narrow Bridge
One Lane Bridge
Divided Highway Ends
Two-Way Traffic
Hill
Bump
Dip
Pavement Ends
Soft Shoulder
Two-Direction Large Arrow
Be Prepared to Stop
Truck Crossing
Truck
Right Lane Ends
Golf Cart
Bridge Ices Before RoadDMV Decoded is an independent guide, not a government agency. Check your state's driver handbook for the signs on its test.