What Does P1721 Mean?
The wheel speed sensor signal from sensor number 3 is outside expected parameters during operation. This indicates the sensor reading is either too high, too low, or erratic compared to other wheel speed sensors.
Common Causes
40%
Faulty wheel speed sensor at position 3
25%
Damaged or missing tone ring teeth at wheel bearing hub
20%
Excessive wheel bearing play or worn hub bearing
15%
Wiring or connector issues in wheel speed sensor circuit
Diagnostic Steps
1
Step 1: Identify which wheel position is sensor 3 (typically right rear, but varies by manufacturer)
2
Step 2: Inspect wheel speed sensor for physical damage, debris buildup, or improper air gap
3
Step 3: Check wheel bearing for excessive play by lifting vehicle and attempting to rock wheel
4
Step 4: Inspect tone ring for damage, missing teeth, or excessive runout
5
Step 5: Compare live data readings from all four wheel speed sensors while driving to identify discrepancies
Estimated Repair Cost
$120 - $600
Parts + labor, varies by vehicle and location
The wheel speed sensor signal from sensor number 3 is outside expected parameters during operation. This indicates the sensor reading is either too high, too low, or erratic compared to other wheel speed sensors.
The most common cause of P1721 (Wheel Speed Signal 3 Range/Performance) is: Faulty wheel speed sensor at position 3
Typical repair costs for P1721 range from $120 to $600, depending on the vehicle, location, and whether you do it yourself or go to a shop.
May disable ABS and traction control systems, reducing vehicle stability in emergency braking or slippery conditions. ABS warning light will typically illuminate.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P1721 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Anti-lock Brake System / Traction Control
Difficulty
Type
Manufacturer
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
