What Does C1447 Mean?
This code indicates a communication or circuit failure between the traction control module and its request line to other vehicle systems. The traction control module uses this circuit to request engine torque reduction from the PCM and/or brake application from the ABS hydraulic unit when wheel spin is detected. A failure here means traction control cannot coordinate with the engine or brakes to regain traction, even though it may still detect wheel slip.
Common Causes
35%
Open or high resistance in the dedicated traction control request wire between the TC module and PCM/ABS module
25%
CAN bus communication fault preventing the traction control module from sending torque reduction requests to the PCM
25%
Faulty traction control module output driver circuit that generates the request signal
15%
PCM not acknowledging traction control requests due to PCM fault or software incompatibility after module replacement
Diagnostic Steps
1
Step 1: Check for related DTCs in the PCM and ABS module. If CAN communication codes are present in multiple modules, the root cause is likely a CAN bus wiring fault rather than a traction control-specific issue.
2
Step 2: Identify whether the TC request circuit is a dedicated hardwired signal or a CAN bus message by consulting the vehicle wiring diagram. For hardwired systems, test continuity and voltage on the request wire between the TC module and PCM.
3
Step 3: For CAN-based systems, use a scan tool to verify that the traction control module is visible on the network and is transmitting messages. Check the CAN bus for excessive error frames that might indicate a noisy or damaged bus.
4
Step 4: Verify that all module software levels are compatible, especially if any module has been recently replaced or reprogrammed. A software version mismatch can prevent proper handshake on the TC request protocol.
5
Step 5: If the TC module has a dedicated relay for its request circuit, check the relay for proper operation. Measure relay coil resistance (typically 60-100 ohms) and verify contact closure with a DVOM.
Estimated Repair Cost
$150 - $800
Parts + labor, varies by vehicle and location
This code indicates a communication or circuit failure between the traction control module and its request line to other vehicle systems. The traction control module uses this circuit to request engine torque reduction from the PCM and/or brake application from the ABS hydraulic unit when wheel spin...
The most common cause of C1447 (Traction Control Module Request Circuit Failure) is: Open or high resistance in the dedicated traction control request wire between the TC module and PCM/ABS module
Typical repair costs for C1447 range from $150 to $800, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Traction control will be unable to reduce engine power or apply brakes to spinning wheels. On slippery surfaces, excessive wheel spin may cause loss of directional control during acceleration, particularly in rear-wheel-drive vehicles.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to C1447 to identify the root cause.
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Quick Info
Category
Chassis
System
Traction Control System
Difficulty
Type
Manufacturer
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