C121C Mitsubishi Code - Torque Request Signal Denied
Quick Answer
The Anti-Lock Brake System (ABS) Module monitors the Yaw Control/Traction Control System. Common causes include Faulty Anti-Lock Brake System (ABS) Module, Faulty Powertrain Control Module (PCM). 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
- C121C Mitsubishi indicates Torque Request Signal Denied.
- Common causes
- Common causes include Faulty Anti-Lock Brake System (ABS) Module, Faulty Powertrain Control Module (PCM).
- 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 C121C Mitsubishi Description
What are the Possible Causes of the DTC C121C Mitsubishi?
- Faulty Anti-Lock Brake System (ABS) Module
- Faulty Powertrain Control Module (PCM)
How to Fix the DTC C121C Mitsubishi?
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 C121C Mitsubishi 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.
Need more information about the C121C Mitsubishi code?
Need more information on how to fix the C121C Mitsubishi code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the C121C Mitsubishi code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about C121C Mitsubishi Code
1. What does the OBDII code C121C mean for a Mitsubishi vehicle?
C121C indicates a "Torque Request Signal Denied," meaning the Engine Control Module (ECM) and other control modules are not properly communicating torque requests or responses.
2. What are the common symptoms of the C121C code in a Mitsubishi?
Symptoms may include the ABS or traction control warning light staying on, reduced engine performance, and possible loss of stability control or traction assistance.
3. What causes the C121C code to trigger?
Common causes include faulty communication between the ECM and ABS module, a malfunctioning ECM, damaged wiring, or corroded electrical connections.
4. Can a low battery cause the C121C code?
Yes, a low or weak battery can lead to voltage irregularities that disrupt module communication and trigger this code.
5. How do you diagnose the C121C code on a Mitsubishi vehicle?
Diagnosis involves scanning for codes using an OBDII scanner, inspecting wiring and connectors for damage or corrosion, and testing the ECM and ABS module for proper operation.
6. Is it safe to drive with the C121C code present?
It may be unsafe, as the vehicle's traction control or ABS systems could be compromised, increasing the risk of losing control in slippery conditions.
7. How can the C121C code be fixed?
Repairs may include cleaning or replacing corroded connectors, repairing damaged wiring, updating/reprogramming the ECM, or replacing a faulty control module.
8. Can clearing the C121C code solve the issue?
Clearing the code may temporarily remove the warning light, but if the underlying issue is not resolved, the code is likely to reappear.
9. What tools are needed to troubleshoot the C121C code?
An OBDII scanner, multimeter, and possibly specialized diagnostic tools for Mitsubishi vehicles are needed to properly diagnose and repair this code.
10. Does the C121C code always require module replacement?
No, module replacement is not always necessary. The issue may be resolved by addressing wiring, updating software, or fixing communication errors between modules.
Discuss the causes and fixes for C121C Mitsubishi OBDII Code
Code C121C Mitsubishi comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
