P1720: On Nissan, vehicle speed sensor (automatic transmission output) fault
Nissan vehicle speed sensor, A/T output
Severity: Inspect soon
CarsCounsel rates P1720 moderate to high and does not recommend driving if shifting is erratic or the speedometer is dead.
It gets more serious if:
- Stop: Shifting is erratic, the transmission is in limp mode or the speedometer is dead. CarsCounsel does not recommend driving in that state.
P1720 in short
On Nissan, P1720 means the vehicle speed sensor signal for the automatic transmission output is missing or not believable. Wiring, the sensor, the tone ring or a network fault can cause it. A dead speedometer and harsh shifting are common, so have it inspected soon.
The transmission computer uses a vehicle speed signal to decide when to shift. On Nissan, P1720 is the fault for the transmission output speed sensor, shown as V/SP SEN (A/T OUT), and the same signal feeds the instrument cluster.
CarsCounsel lists wiring and connectors, the speed sensor, the tone ring and module or network faults, and symptoms such as an erratic or dead speedometer, harsh shifting and limp mode.
Nissan bulletin 05027 covers a 2005 Pathfinder 4WD with P1720 stored in the engine module. Other makers use P1720 differently, and we only sourced the Nissan meaning.
Pick your make
P1720 is a manufacturer-specific code: its meaning depends on who built the car.
Other makes: meaning not verified. Check with a scan tool that reads manufacturer definitions.
Most likely causes
Cause 1: Wiring or connector fault in the speed sensor circuit
Common general cause- Why it ranks here
- CarsCounsel lists wiring and connectors, and this is a signal fault.
- What would change this
- Rises if the speedometer is erratic and the harness is damaged.
Cause 2: Failed vehicle speed sensor
Common general cause- Why it ranks here
- CarsCounsel lists the speed sensor itself.
- What would change this
- Rises if the wiring tests good and the signal is missing.
Cause 3: Damaged tone ring or reluctor
Possible — needs testing- Why it ranks here
- CarsCounsel lists the tone ring; it needs a teardown to see.
- What would change this
- Rises if the sensor and wiring test good and the signal is erratic.
Cause 4: Speed signal fault stored in the engine module (2005 Pathfinder 4WD)
Supported by vehicle data- Why it ranks here
- Nissan 05027 covers P1720 V/SP SEN (A/T OUT) stored in the engine module on this vehicle.
- What would change this
- Rises on a covered 4WD Pathfinder.
Cause 5: Module or network fault
Possible — needs testing- Why it ranks here
- CarsCounsel lists module and network faults.
- What would change this
- Rises if other communication codes are stored.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Read codes from the engine and transmission modules with a scan tool that supports both, before anything is cleared. Note ABS, speed or communication codes.
If2005 Pathfinder 4WD with P1720 in the engine module
It meansCheck the Nissan bulletin.
Points to: Speed signal fault stored in the engine module (2005 Pathfinder 4WD)
IfCommunication codes are also stored
It meansSuspect a network fault.
IfP1720 alone
It meansWatch the speedometer, then inspect the wiring.
Step 2: Inspect the speed sensor connector and harness for chafing, corrosion and oil inside the plug.
IfDamage or corrosion is found
It meansRepair it and retest.
Points to: Wiring or connector fault in the speed sensor circuit
IfWiring looks fine
It meansA shop should test the sensor signal.
Step 3: Have a shop check the speed sensor signal on a scan tool while the car is driven, and inspect the tone ring if the signal is erratic.
Warning:Shop test. It needs the maker's specifications.
IfSignal is missing and the circuit is good
It meansThe sensor has failed.
IfSignal is erratic with a good sensor
It meansInspect the tone ring.
Symptoms
- Check engine light
- Speedometer reads zero or jumps Gets more serious: stop and have it checked.
- Harsh shifting or limp mode Gets more serious: stop and have it checked.
How to fix
Step 1: Do not clear the code before the transmission module has been read.
Parts and cost context
- Transmission control module (TCM):Do not replace the module for P1720 unless tests point to it.
Labor varies by vehicle and shop; get a quote before you approve a repair.
Compare used part prices on PartPriceGuideOn your vehicle
NissanYour car
2005 · Pathfinder
Supported by vehicle data2005 Pathfinder with 4WD: DTC P1720 V/SP SEN (A/T OUT) stored in the ECM. Whether the bulletin is still current is not verified.
05027Status unverified
Nissan 05027: 2005 Pathfinder 4WD, P1720 V/SP SEN (A/T OUT) stored in the ECM
2005pathfinder · NHTSA 10015998
2005 Pathfinder with 4WD: DTC P1720 V/SP SEN (A/T OUT) stored in the ECM.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
Related codes
No curated relationships for P1720 yet.
P1720 questions
What does P1720 mean on other makes?
We only sourced the Nissan meaning. Other makers use this number for different faults, so check the maker's own information.
Can I drive with P1720?
CarsCounsel rates it moderate to high and does not recommend driving if shifting is erratic or the speedometer is dead.
Sources and review
- P1720 Code: Nissan Vehicle Speed Sensor
- Nissan 05027: 2005 Pathfinder 4WD, P1720 V/SP SEN (A/T OUT) stored in the ECM
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error