C1203 Code - ECM Communication Circuit Malfunction
Quick Answer
The circuit is used to send Traction Control (TRAC) and Vehicle Stability Control (VSC) control information from the Skid Control ECU (Brake Actuator Assembly) to the Engine Control Module (ECM), and engine control information from the ECM to the Skid Control ECU (Brake Actuator Assembly) through the Controller Area Network (CAN) communication system. Common causes include Faulty Engine Control Module (ECM), Incorrect Engine Control Module Installed, Faulty Skid Control ECU (Brake Actuator Assembly). 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
- C1203 indicates ECM Communication Circuit Malfunction.
- Common causes
- Common causes include Faulty Engine Control Module (ECM), Incorrect Engine Control Module Installed, Faulty Skid Control ECU (Brake Actuator Assembly).
- 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 C1203 Description
What are the Possible Causes of the DTC C1203?
- Faulty Engine Control Module (ECM)
- Incorrect Engine Control Module Installed
- Faulty Skid Control ECU (Brake Actuator Assembly)
How to Fix the DTC C1203?
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.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the C1203 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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Information for Specific Makes
- C1203 Buick — Right Front Wheel Speed Sensor Circuit Open or Shorted
- C1203 Cadillac — Right Front Wheel Speed Sensor Circuit Open or Shorted
- C1203 Chevrolet — Right Front Wheel Speed Sensor Circuit Open or Shorted
- C1203 Ford — ABS Rear Dump Valve Circuit Open
- C1203 GMC — Right Front Wheel Speed Sensor Circuit Open or Shorted
- C1203 Hyundai — Front Right Wheel Speed Sensor Open Or Short
- C1203 KIA — Front Right Wheel Speed Sensor Open Or Short
- C1203 Lexus — ECM Communication Circuit Malfunction
- C1203 Lincoln — ABS Rear Dump Valve Circuit Open
- C1203 Mercury — ABS Rear Dump Valve Circuit Open
- C1203 Scion — ECM Communication Circuit Malfunction
- C1203 Toyota — ECM Communication Circuit Malfunction
Frequently Asked Questions about C1203 Code
1. What are the common symptoms of OBDII code C1203 ECM Communication Circuit Malfunction?
- The common symptoms include the Check Engine Light illuminating on the dashboard, issues with engine performance such as stalling or rough idling, and possible difficulty starting the vehicle.
2. What are the potential causes of OBDII code C1203 ECM Communication Circuit Malfunction?
- The code can be triggered by problems with the Electronic Control Module (ECM), damaged wiring in the communication circuit, faulty sensors, or issues with the CAN (Controller Area Network) bus.
3. How can I diagnose the OBDII code C1203 ECM Communication Circuit Malfunction?
- Diagnosis typically involves using an OBDII scanner to retrieve the trouble codes, checking the communication circuit for any visible damage, and testing the ECM and related components for proper functionality.
4. What are some repair tips for addressing OBDII code C1203 ECM Communication Circuit Malfunction?
- Repair tips may include repairing or replacing damaged wiring in the communication circuit, addressing any issues with the ECM or related components, and ensuring proper connections and grounds.
5. Can I drive my vehicle with OBDII code C1203 ECM Communication Circuit Malfunction?
- It is not recommended to drive the vehicle with this code present, as it can lead to further damage and potential safety hazards. It is best to address the issue promptly.
6. How much does it cost to repair OBDII code C1203 ECM Communication Circuit Malfunction?
- The cost of repair can vary depending on the underlying cause of the issue, the labor rates of the repair shop, and the cost of any replacement parts needed. It is advisable to get a few quotes from trusted mechanics.
7. Are there any recalls related to OBDII code C1203 ECM Communication Circuit Malfunction?
- It is advisable to check with the vehicle manufacturer or the National Highway Traffic Safety Administration (NHTSA) website to see if there are any recalls related to this specific OBDII code for your vehicle.
8. Can a DIY enthusiast fix OBDII code C1203 ECM Communication Circuit Malfunction?
- Depending on the skill level and experience of the DIY enthusiast, some repairs related to this code may be possible to do at home. However, complex issues may require professional diagnosis and repair.
9. How long does it take to repair OBDII code C1203 ECM Communication Circuit Malfunction?
- The repair time can vary based on the specific cause of the issue, the availability of parts, and the workload of the repair shop. Some repairs may be completed within a few hours, while others may take longer.
10. Will resetting the OBDII code C1203 ECM Communication Circuit Malfunction make it go away permanently?
- Resetting the code may temporarily turn off the Check Engine Light, but if the underlying issue is not addressed, the code is likely to return. It is crucial to diagnose and repair the root cause of the problem.
Discuss the causes and fixes for C1203 OBDII Code
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I have a 2012 camry hybrid i replaced the ABS actuator complete unit after replace that my all problem slow abu still ABS light on position. DTC cord C1203 coming .......?
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Either you installed an incorrect control unit (ABS actuator) or you have not perform a control unit initialization. You need the Toyota computer to perform initialization.
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