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C1203 Toyota Code - ECM Communication Circuit Malfunction

- Code Popularity: 91,483 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC C1203 Toyota?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Engine Control Module (ECM)
  • Incorrect Engine Control Module Installed
  • Faulty Skid Control ECU (Brake Actuator Assembly)
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How to Fix the DTC C1203 Toyota?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

Code Tech Notes

DTC C1203/95 is output when an incorrect Engine Control Module (ECM) is installed. If initialization is performed and learning occurs with an incorrect Engine Control Module installed, operations and functions will differ from those stored when the vehicle was shipped from the factory. Therefore, make sure that learning occurs properly.

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the C1203 Toyota code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Anti-Lock Brake System (ABS) Warning Light ON
  • Engine Light ON (or Service Engine Soon Warning Light)

Code C1203 Toyota Description

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.

OBDII Code C1203 Toyota - ECM Communication Circuit Malfunction - AutoCodes.com
C1203 Toyota Code - ECM Communication Circuit Malfunction

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Code C1203 Toyota comments

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