LEFT-TURN SIGNAL SELECTION

WHICH SIGNAL FACES WORK IN WHAT CIRCUMSTANCES?

SIGNAL SELECTION
LEFT
TURN
SIGNAL
FACE		 C
A
S
E		 ONCOMING LEFT TURN FACES LEFT
TURN
LANE
NEEDED
TO USE		 LEFT
TURN
MODES
ALLOWED		 SIGNAL
PHASE
ORDERS
ALLOWED		 WALK
SIGNAL
PHASES
ALLOWED		 RIGHT TURN OVERLAP FACES
perm circ fya 3 5 sec perm fya 4 prot fya 3 5 sec perm fya 4 prot
perm circ A
L
L		 OKNO USETRAP? NO USETRAP? NO Permissive Permissive,
Single lead,†
Split phase		 All Walk,
Thru overlap		 ALL FYA
U YIELD		 THRU:
CIRC GRN
NO X LEFT
U YIELD		 NO USE NO USE
fya 3 A
L
L		 NO USEOKNO USE SAFESAFE YES Permissive Permissive,
Single lead,
Single lag,
Split phase		 All Walk,
Thru overlap
No reservice		 ALL FYA
U YIELD		 THRU:
CIRC GRN
NO X LEFT
U YIELD		 THRU:
FYA
NO X LEFT
U YIELD		 NO USE
5 sec perm S P
P H
L A
I S
T E		 OK*OK*OK* OK*OK* NO Split phase Split phase All Walk,
Thru overlap		 ALL FYA
U YIELD		 THRU:
CIRC GRN
X LEFT:
GRN ARR
NO U		 THRU: FYA
X LEFT:
FYA &
U YIELD,
OR
GRN ARR
& NO U		 THRU:
RED ARR
OR TRAP?
X LEFT:
GRN ARR
NO U
5 sec perm   O
A T
L H
L E
  R		 TRAP?NO USETRAP? TRAP?
LIMIT USE		TRAP? If red &
green on
at same
time		 Any†
 Leading /w
anti-backup		 All Walk,
Thru overlap		 ALL FYA
U YIELD		 THRU:
CIRC GRN
X LEFT:
GRN ARR
NO U		 THRU: FYA
X LEFT:
FYA &
U YIELD,
OR
GRN ARR
& NO U		 THRU:
RED ARR
OR TRAP?
X LEFT:
GRN ARR
NO U
fya 4 A
L
L		 NO USESAFETRAP? SAFESAFE MUST
HAVE		 Any Any† All Walk,
Thru overlap
No reservice		 ALL FYA
U YIELD		 THRU:
CIRC GRN
X LEFT:
GRN ARR
NO U		 THRU: FYA
X LEFT:
FYA &
U YIELD,
OR
GRN ARR
& NO U		 THRU:
RED ARR
OR TRAP?
X LEFT:
GRN ARR
NO U
prot A
L
L		 TRAP?SAFETRAP? SAFESAFE If red &
green on
at same
time		 Any, No
permissive		 Any† All Walk,
Thru overlap		 ALL FYA
U YIELD		 THRU:
CIRC GRN
X LEFT:
GRN ARR
NO U		 THRU: FYA
X LEFT:
FYA &
U YIELD,
OR
GRN ARR
& NO U		 THRU:
RED ARR
OR TRAP?
X LEFT:
GRN ARR
NO U

*         - No oncoming traffic may have a green when this leg has a green.

†         - Must test for yellow trap if not a standard flashing yellow arrow (FYA) configuration.

FYA       - Flashing Yellow Arrow.

NO USE    - These signal faces can't be used together for left turns coming from opposite directions.

TRAP?     - This configuration must be tested and sequence-limited to prevent yellow trap.

OK        - These signal faces can be used together for left turns from opposite directions.

SAFE      - These signal faces properly used together prevent yellow trap without sequence limits.

OR TRAP?  - If a green arrow is used, yellow trap must be prevented at the end of the green arrow.

LIMIT USE - These are allowed together only if a lane-use restriction prevents FYA use on one leg.
            Must be tested and sequence-limited to prevent yellow trap.

U YIELD   - U-turns must yield to turns on red. Turns on red can't know if cars are turning left or U.

NO U      - If right green arrow is used, U-turns must be prohibited into the same leg.

Reservice - If a walk occurs before an FYA left begins, starting the walk again causes yellow trap.
            But if the FYA is operated concurrently with the walk, no yellow trap happens.

Lane-use  - If FYA signals are used, left turns must not share lanes with other movements.
 

Red & green on at the same time - When movements share a lane, all must stop and must go together.