DTC 4343

^ Open or shorted circuit to carbon canister frequency valve.

This code may be caused by:

a. Fuse #28 in fuse relay panel blown. If this is the case, codes 2411, 4312, and 4331 should also be present. Check for short to ground in EGR frequency valve, carbon canister frequency valve, carbon canister shut-off valve and/or oxygen sensor heating element.
b. Faulty fuel pump relay (no power to frequency valve).
c. Open circuit between fuse #28 and carbon canister frequency valve terminal #1 (no power to valve).
d. Open or grounded circuit between carbon canister frequency valve terminal #2 and ECU terminal 12D.
e. Faulty carbon canister frequency valve.