Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the sensor that tells the car how fast the right rear wheel is spinning. It's like a broken speedometer for that wheel.
The C122C code indicates an electrical issue with the right rear wheel speed sensor circuit, which affects the vehicle's ability to monitor wheel speed accurately.
The right rear wheel speed sensor is part of the ABS (Anti-lock Braking System) and traction control system. It sends signals to the vehicle's ECU (Engine Control Unit) to help determine wheel speed. An electrical fault in this circuit can lead to improper ABS and traction control functioning.
• ABS warning light on
• Traction control light on
• Inconsistent speedometer readings
• Faulty right rear wheel speed sensor
• Damaged or corroded wiring/connectors
• Faulty ABS module
ABS: Anti-lock Braking System
ECU: Engine Control Unit
• Visually inspect the right rear wheel speed sensor and wiring for damage.
• Use a multimeter to test the sensor's electrical resistance.
• Check the ABS module for fault codes and proper operation.
• Replace the faulty right rear wheel speed sensor.
• Repair or replace damaged wiring/connectors.
• Replace the ABS module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Dodge Charger
• Jeep Grand Cherokee
• Chrysler 300
• Regularly inspect wheel speed sensors and wiring.
• Avoid driving in harsh conditions that can damage sensors.
• Perform routine ABS system checks.
Sensor Issue
• Have the vehicle inspected by a professional if the ABS light is on.
• Avoid driving in conditions where traction is critical until repaired.
Check with the vehicle manufacturer for warranty coverage on ABS components.
This code has been reported in various models, often due to environmental factors affecting sensor integrity.
Moderate – While the vehicle may still be drivable, the ABS and traction control systems may not function properly, increasing the risk of skidding.
Driving with a malfunctioning ABS system can be dangerous and may not comply with safety regulations.
• Vehicle parked and engine off
• Access to the right rear wheel area
The right rear wheel speed sensor is located near the wheel hub of the right rear wheel.
Q: Can I drive with a C122C code?
A: It's possible, but not recommended as the ABS and traction control systems may not work properly.
Q: How do I reset the ABS light?
A: Fix the underlying issue first, then use an OBD-II scanner to clear the code.
Pro · Four-system diagnostics
A handheld scanner aimed at engine, transmission, ABS, and airbag diagnostic work.
Chassis and ABS faults usually need a scanner that can read brake-system data directly.
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Universal · Torque wrench
Useful when reassembly torque matters for wheel, suspension, and under-hood fasteners.
Useful when wheel, hub, or suspension hardware needs correct reassembly torque.
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Universal · Drive-on ramps
Helpful for safer access underneath the vehicle during exhaust, EVAP, and underbody inspection work.
Helpful for safer access during underbody inspection work.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.