P1605high severityPowertrain
A/T Diagnostic Communication Line
on 2021 Nissan Frontier 3.8L V6 · 4WD
What this code means
Failure in communication between ECM and TCM.
Symptoms
- CEL
- Trans stuck in failsafe
- No shifting past 2nd/3rd
- Overdrive light off
Common causes
- Blown A/T fuse
- Faulty TCM
- Damaged communication wiring
- Corroded connectors
Diagnostic steps
- Check A/T fuse
- Test communication line
- Inspect connectors
- Test TCM
Repair notes
Repair communication line or replace fuse.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1