C120B 2018 Toyota RAV4 Code - Ignition Supply Voltage Low
Quick Answer
The Diagnostic Trouble Code (DTC) will be set when the Master Cylinder Pressure Sensor power supply voltage decrease occurs, or a history of voltage decrease exists, and defective Master Cylinder Pressure Sensor output continues for 1 second or more. Common causes include Faulty Master Cylinder Pressure Sensor, Master Cylinder Pressure Sensor harness is open or shorted, Master Cylinder Pressure Sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- C120B 2018 Toyota RAV4 indicates Ignition Supply Voltage Low.
- Common causes
- Common causes include Faulty Master Cylinder Pressure Sensor, Master Cylinder Pressure Sensor harness is open or shorted, Master Cylinder Pressure Sensor circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code C120B 2018 Toyota RAV4 Description
What are the Possible Causes of the DTC C120B 2018 Toyota RAV4?
- Faulty Master Cylinder Pressure Sensor
- Master Cylinder Pressure Sensor harness is open or shorted
- Master Cylinder Pressure Sensor circuit poor electrical connection
- Faulty Skid Control ECU (Brake Actuator Assembly)
How to Fix the DTC C120B 2018 Toyota RAV4?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the C120B 2018 Toyota RAV4 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about C120B 2018 Toyota RAV4 Code
1. What does the OBDII code C120B mean on a 2018 Toyota RAV4?
C120B indicates "Ignition Supply Voltage Low," meaning the Anti-lock Brake System (ABS) module is detecting insufficient voltage from the ignition circuit.
2. What are the common symptoms of the C120B code in a 2018 Toyota RAV4?
Symptoms may include the ABS warning light illuminating, poor ABS or traction control performance, or intermittent electrical issues.
3. What can cause the C120B code to appear on a 2018 Toyota RAV4?
Causes may include a weak or failing battery, corroded or loose battery terminals, damaged wiring in the ignition circuit, or a faulty ABS module.
4. How can I diagnose the C120B code on my 2018 Toyota RAV4?
Start by checking the battery voltage and condition, inspect the battery terminals and related wiring for corrosion or damage, and use a multimeter to test the ignition circuit.
5. Can a low battery cause the C120B code on a 2018 Toyota RAV4?
Yes, a low or failing battery is one of the most common causes of this code, as it can lead to insufficient ignition supply voltage.
6. Is it safe to drive my 2018 Toyota RAV4 with the C120B code active?
While the vehicle may still be drivable, the ABS and traction control systems may not function properly, potentially compromising safety in certain driving conditions.
7. How can I fix the C120B code on a 2018 Toyota RAV4?
Repairs may include replacing a failing battery, cleaning or tightening battery terminals, repairing damaged wiring, or replacing the ABS module if necessary.
8. How much does it cost to fix the C120B code on a 2018 Toyota RAV4?
Costs can vary depending on the issue. Battery replacement typically costs $100-$300, while ABS module repairs or replacements can range from $500-$1,500.
9. Can a loose connection cause the C120B code in a 2018 Toyota RAV4?
Yes, loose or corroded battery terminals or damaged wiring connections can lead to voltage drops and trigger this code.
10. How do I prevent the C120B code from returning on my 2018 Toyota RAV4?
Regularly inspect and maintain the battery, ensure terminals are clean and secure, and promptly address any electrical issues to prevent voltage-related problems.
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