C1A72 Code - Communication Error from FCM to Driving Support ECU
Quick Answer
If a communication error between the Driving Support ECU Assembly and Forward Recognition Camera is detected, Diagnostic Trouble Code (DTC) C1A72 is stored. Common causes include Faulty Controller Area Network (CAN) Communication System, Faulty Forward Recognition Camera, Faulty Driving Support ECU 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
- C1A72 indicates Communication Error from FCM to Driving Support ECU.
- Common causes
- Common causes include Faulty Controller Area Network (CAN) Communication System, Faulty Forward Recognition Camera, Faulty Driving Support ECU 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 C1A72 Description
What are the Possible Causes of the DTC C1A72?
- Faulty Controller Area Network (CAN) Communication System
- Faulty Forward Recognition Camera
- Faulty Driving Support ECU Assembly
How to Fix the DTC C1A72?
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
If the Forward Recognition Camera has been replaced with a new one, be sure to perform Forward Recognition Camera learning.
When replacing the Driving Support ECU Assembly, always replace it with a new one. If a Driving Support ECU Assembly which was installed in another vehicle is used, the information stored in the Driving Support ECU Assembly will not match the information from the vehicle. As a result, a DTC may be stored.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the C1A72 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
- C1A72 Lexus — Communication Error from FCM to Driving Support ECU
- C1A72 Toyota — Communication Error from FCM to Driving Support ECU
Frequently Asked Questions about C1A72 Code
What does the OBDII code C1A72 mean?
C1A72 indicates a communication error between the Forward Collision Mitigation (FCM) system and the Driving Support ECU, meaning data exchange between these components is disrupted.
What are common symptoms of the C1A72 code?
Symptoms may include illuminated warning lights (like the check engine or collision mitigation system light), deactivated driver assistance features, or erratic system behavior.
What causes the C1A72 code to trigger?
The code can be caused by faulty wiring, a damaged FCM module, a malfunctioning Driving Support ECU, or software issues in either module.
Can a weak battery cause the C1A72 code?
Yes, a weak or failing battery can lead to voltage irregularities, which may disrupt communication between the FCM and Driving Support ECU.
How is the C1A72 code diagnosed?
Technicians use a scan tool to verify the code, inspect wiring and connectors between the FCM and Driving Support ECU, and test the functionality of both modules.
Can I still drive with the C1A72 code active?
While the vehicle may still be drivable, driver assistance features like collision mitigation may not function, increasing the risk of an accident.
How can the C1A72 code be fixed?
Repairs may include checking and repairing wiring, replacing faulty connectors, updating module software, or replacing the FCM or Driving Support ECU if necessary.
Does the C1A72 code require reprogramming?
If the issue is due to outdated software, reprogramming or updating the affected modules may resolve the problem.
What tools are needed to fix the C1A72 code?
A diagnostic scan tool, a multimeter for electrical testing, and possibly manufacturer-specific tools for reprogramming or module replacement are required.
Is the C1A72 code covered under warranty?
It depends on the vehicle’s warranty terms and whether the issue is related to a defective part or wear and tear. Consult your warranty documentation or dealership for confirmation.
Discuss the causes and fixes for C1A72 OBDII Code
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