P1791moderate severityPowertrain
Vehicle Speed Signal Malfunction (from A/T)
on 2016 Honda Civic 1.5L I4 Turbo · FWD
What this code means
The transmission control system is not receiving a valid vehicle speed signal. This disrupts shift timing and lock-up control.
Symptoms
- Erratic shifting
- Speedometer issues
- Check engine light on
Common causes
- Faulty vehicle speed sensor
- Damaged wiring or connector
- Poor signal ground
- Faulty PCM
Diagnostic steps
- Scan for stored codes
- Inspect VSS wiring and connector
- Test speed sensor signal output
- Replace sensor if faulty
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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