Severity Medium
C1403

C1403: RF Traction Control Valve Short to Battery

📅 Last reviewed: July 2026
What does the C1403 code mean?

Diagnostic trouble code C1403 indicates a short circuit to battery positive voltage in the right front traction control valve circuit. This valve is part of the vehicle's stability and traction control system, regulating hydraulic pressure to the right front brake to prevent wheel slip. The control module detects that the valve circuit is continuously at battery voltage when it should not be, preventing proper traction and stability system operation.

Medium
Severity
Variable
Typical Cost
Medium
Frequency

1. Commonly Affected Makes

ToyotaLexus

2. Most Common Causes

3. Symptoms You Will Notice

4. Step-by-Step Diagnosis

1

Scan for additional codes and check freeze frame data

2

Visually inspect right front traction control valve connector and wiring for damage, corrosion, or shorts

3

Disconnect valve connector and measure resistance across valve solenoid; compare to specifications

4

Check for battery voltage at valve circuit with ignition on; if present when valve should be off, trace short

5

Inspect wiring harness for chafing or contact with 12V sources

6

If wiring and valve test OK, suspect faulty ABS/VSC module

5. Frequently Asked Questions

Is it safe to drive?

The vehicle may be driven with caution, but traction and stability control will be disabled, increasing risk of loss of control in slippery conditions. Have the issue diagnosed and repaired promptly.

How much does it cost to fix?

Repair costs typically range from $150 to $600, depending on whether the issue is a simple wiring repair or requires replacement of the traction control valve or ABS module.

6. Related Codes

Need an OBD2 Scanner for the C1403? Compare the best scanners compatible with all vehicles
🛒 View OBD2 Scanners →