Are you facing transmission issues with your Nissan? The culprit might be a faulty speed sensor. Finding the right sensor location can save you hundreds in mechanic fees if you’re willing to tackle this repair yourself. This guide will walk you through exactly where to find these crucial components on your Nissan’s CVT transmission and provide practical tips for replacement.
What Is a CVT Transmission Speed Sensor?
Your Nissan’s Continuously Variable Transmission (CVT) relies on two main speed sensors to function properly. These small electronic components monitor how fast different parts of your transmission are moving and relay that information to your car’s computer.
The two main sensors are:
- Primary (Input) Speed Sensor: Measures the rotational speed coming from the engine
- Secondary (Output) Speed Sensor: Tracks the transmission output shaft speed
When either sensor fails, you’ll typically notice jerky shifting, limited speed capability, or even your vehicle going into “limp mode” with a dashboard warning light.
Where Are the Speed Sensors Located on a Nissan CVT?
The speed sensors on most Nissan vehicles with CVT transmissions are mounted directly on the transmission case. While the exact location varies slightly by model, they follow a consistent pattern across the Nissan lineup.
Primary (Input) Speed Sensor Location
On most Nissan models, you’ll find the primary speed sensor:
- On the driver’s side of the transmission
- Usually positioned below or near the starter motor
- Facing toward the front of the vehicle
- Accessible from underneath or after removing the left front wheel and splash shield
To visualize this location, imagine standing in front of your car looking at the engine bay. The primary sensor would be on the left side (driver’s side) of the transmission, often partially hidden by other components.
Secondary (Output) Speed Sensor Location
The secondary speed sensor is typically found:
- Also on the driver’s side of the transmission case
- Positioned toward the top or rear of the transmission
- Near the CV axle where it connects to the transmission
- Often requiring removal of the driver’s side wheel and splash shield for access
Locating Speed Sensors on Popular Nissan Models
Different Nissan models have slight variations in sensor placement. Here’s a breakdown of where to find them on common models:
Nissan Altima (2012-2018)
The Altima is one of Nissan’s most popular models with a CVT transmission. On these vehicles:
- Primary Sensor: Located on the driver’s side of the transmission, below the starter. You can access it by removing the wheel and splash shield, or from above by removing the battery and air intake components.
- Secondary Sensor: Found near the CV axle on the driver’s side, toward the rear of the transmission case.
Many Altima owners find it easier to access the primary sensor from underneath after removing the splash shield, as demonstrated in this helpful video guide.
Nissan Rogue
On the Nissan Rogue, the sensors follow a similar pattern:
- Primary Sensor: Positioned on the driver’s side, below the starter motor
- Secondary Sensor: Located at the top/rear of the transmission near the vent tube and CV axle
For the Rogue, the wheel well and splash shield removal approach typically provides the best access to both sensors. Some Rogue owners have reported success by accessing the area after removing specific components.
Nissan Murano
The Murano’s sensor placement is:
- Primary Sensor: Below the starter/vent tube area on the driver’s side
- Secondary Sensor: On top of the CVT near the breather tube
Access is typically gained from underneath the vehicle on the driver’s side. Murano forums have discussed these locations in detail.
Nissan Quest
The Quest minivan has a slightly different arrangement:
- Primary Sensor: Positioned between the radiator and transmission housing on the driver’s side
- Secondary Sensor: Some models may use a single sensor configuration
How to Access the Speed Sensors
Accessing these sensors typically requires some disassembly. Here’s a general approach that works for most Nissan models:
Method 1: From Underneath (Most Common)
- Safely raise and secure the vehicle on jack stands
- Remove the driver’s side front wheel
- Remove the plastic splash shield/engine guard (usually held by plastic clips and 10mm bolts)
- Locate the sensor near the areas described above
- Disconnect the electrical connector and remove the 10mm bolt holding the sensor in place
Method 2: From Above (Alternative for Some Models)
- Disconnect the vehicle’s battery
- Remove the air intake assembly
- On some models, remove the battery and battery tray
- Look down toward the transmission to locate the sensor
- Disconnect the electrical connector and remove the mounting bolt
Tools Needed for Speed Sensor Replacement
Before starting this job, gather these tools:
- 10mm socket and ratchet
- Flathead and Phillips screwdrivers
- Pliers for removing electrical connectors
- Jack and jack stands
- Replacement sensor(s)
- Replacement O-ring(s) if not included with new sensor
- Transmission fluid (small amount may leak when sensor is removed)
Detailed Sensor Replacement Procedure
Once you’ve located the sensor, the replacement process is straightforward:
- Disconnect the vehicle’s battery
- Access the sensor using one of the methods described above
- Unplug the electrical connector (usually has a tab you need to press)
- Remove the 10mm bolt holding the sensor in place
- Carefully pull the sensor straight out of the transmission case
- Check the O-ring and replace if damaged
- Install the new sensor with a new or lubricated O-ring
- Tighten the mounting bolt to specification (typically 7-9 ft-lbs)
- Reconnect the electrical connector
- Reinstall any components removed for access
Sensor Comparison Table: Location and Access Methods
| Model | Primary (Input) Sensor | Secondary (Output) Sensor | Easiest Access Method |
|---|---|---|---|
| Altima 2012-2018 | Below starter, side housing | Near CV axle, driver’s side | Wheel off, splash shield removed |
| Rogue | Below starter, side housing | Top/rear trans, near vent/axle | Wheel well & splash shield |
| Murano | Below starter/vent tube area | Top of CVT near breather tube | Under car, driver’s side |
| Quest | Between radiator & trans housing | N/A (single sensor on some) | Under car, driver’s side |
| Sentra | Driver’s side of transmission | Near axle connection | Wheel well access |
Common Symptoms of a Failed Speed Sensor
How do you know if you need to replace a speed sensor? Watch for these telltale signs:
- Check Engine Light or transmission warning light on dashboard
- Car won’t shift properly or gets stuck in one gear
- Vehicle seems to have limited speed capability
- Erratic speedometer readings
- Transmission goes into “limp mode”
- Vehicle hesitates during acceleration
- Error codes P0720, P0721, P0722, P0723 (output sensor) or P0715, P0716, P0717, P0718 (input sensor)
Speed Sensor Testing and Diagnosis
Before replacing a sensor, confirm it’s actually faulty:
- Use an OBD-II Scanner: Connect a scanner to read any error codes. Codes starting with P07xx often indicate transmission sensor issues.
- Visual Inspection: Check for damaged wiring, connectors, or physical damage to the sensor itself.
- Multimeter Testing: You can test the sensor’s resistance with a multimeter if you have the specifications for your particular model.
- Component Testing: Some advanced scanners can perform active tests on the sensors to verify functionality.
Physical Characteristics of CVT Speed Sensors
Knowing what to look for helps identify the sensors:
- Small cylindrical component (about 2-3 inches long)
- Has an electrical connector with 2-3 pins
- Mounted with a single 10mm bolt
- Contains an O-ring seal where it enters the transmission case
- Usually black or gray in color
- Often has metal tip that extends into the transmission
Ordering the Correct Replacement Parts
To ensure you get the right sensor:
- Use your specific Nissan model, year, and engine size when ordering
- Verify whether you need the input or output sensor (or both)
- Consider using OEM (Original Equipment Manufacturer) parts for reliability
- Check if the replacement includes a new O-ring
Most sensors cost between $20-80 depending on whether you choose OEM or aftermarket options. AutoZone and other parts retailers offer both options.
Tips for Successful Sensor Replacement
- Always disconnect the battery before working on electrical components
- Take clear photos before removing components to help with reassembly
- Be gentle when removing the sensor to avoid damaging the transmission housing
- Apply a small amount of transmission fluid to the new sensor’s O-ring before installation
- Ensure the sensor is fully seated before tightening the bolt
- Don’t overtighten the mounting bolt—follow torque specifications
Recent Nissan CVT Issues and Recalls
It’s worth noting that Nissan has faced several class-action lawsuits regarding CVT reliability. While speed sensors are just one potential issue, they’re often misdiagnosed as more serious transmission problems. Replacing a faulty sensor is much less expensive than transmission repair or replacement.
Some owners have reported success fixing transmission problems simply by replacing the speed sensors, so it’s worth checking these components before assuming you need major transmission work.
DIY vs. Professional Replacement
Replacing a speed sensor is within the capabilities of a moderately experienced DIYer. Here’s a comparison:
DIY Replacement:
- Cost: $20-80 for parts
- Time: 1-3 hours depending on experience
- Tools: Basic socket set and jack stands
Professional Replacement:
- Cost: $150-300 including parts and labor
- Time: Usually completed same-day
- Advantage: Warranty on work performed
If you’re comfortable working on your vehicle and have the proper tools, this is definitely a job you can handle yourself. Many owners have successfully completed this repair with the help of online tutorials and YouTube guides.
Prevention and Maintenance
To extend the life of your transmission sensors:
- Keep up with regular transmission fluid changes
- Address check engine lights promptly
- Avoid extreme driving conditions when possible
- Have your vehicle’s computer systems scanned regularly during maintenance
Remember that speed sensors are electronic components that can fail due to age, heat, or vibration, regardless of maintenance. Having a proactive approach to vehicle care can help identify issues before they cause significant problems.
With this guide, you should now have a clear understanding of where to find those elusive speed sensors on your Nissan’s CVT transmission. Whether you’re planning a DIY repair or just want to understand what your mechanic is talking about, knowing these locations and procedures puts you in a better position to maintain your vehicle effectively.
