When C1264 appears, the control module has detected abnormal behavior related to Lamp Warning Relay Circuit Short To Battery in ABS/chassis dynamics and brake control.
C1264 Code: Meaning, Symptoms, Causes & Fix
Overview
Symptoms
- longer braking intervention
- ABS/traction light on
- chassis warning indicator
Common causes
- Open circuit in wiring affecting lamp warning relay circuit short to battery
- Disconnected or loose connector
- Connector pin damage/corrosion or harness stress near related components
How to diagnose C1264
- Confirm C1264 and capture freeze-frame data with a professional scan tool.
- Inspect wiring, connectors, and grounds related to lamp warning relay circuit short to battery for obvious defects.
- Use a continuity test from module pin to component to identify opens/high resistance.
- Check for related DTCs to identify the root-cause chain before replacing parts.
- After repair, clear codes and confirm readiness monitors complete without recurrence.
Severity of code C1264
Moderate: This code is moderate severity: the vehicle may still operate, but fault progression can increase repair cost over time.
Can you drive with C1264?
Most vehicles can be driven short-term with C1264, but postpone heavy load/highway driving until repaired.
If the warning lamp is flashing or drivability/safety is affected, avoid driving and diagnose immediately.
How to fix it (step-by-step)
- Repair obvious wiring/connector faults first to prevent repeat parts replacement.
- Address the root fault mode (open) in the lamp warning relay circuit short to battery circuit/system.
- Apply the required relearn/adaptation procedure if specified by service information.
- Road-test and verify C1264 remains cleared under the conditions that originally set the code.
Fix options
- Restore continuity and verify pin tension.
- Repair open circuit and secure connector lock.
- Clear DTCs and verify with live data and completed drive cycle.
Typical repair cost
$240-$1200
Common mistakes when diagnosing C1264
- Replacing parts without verifying voltage, ground, and signal integrity first.
- Ignoring related stored/pending codes that indicate upstream faults.
- Skipping post-repair verification drive cycle and readiness checks.
C1264 in common vehicles
C1264 appears across makes such as BMW, Mercedes-Benz, Audi, Volvo. Failure patterns differ by platform: wiring routes, software calibration, and component supplier revisions can change root cause.
Frequently asked questions
What causes C1264?
C1264 is commonly set by open faults affecting lamp warning relay circuit short to battery.
How much does it cost to fix C1264?
For C1264, repair costs are typically $240-$1200 depending on exact root cause, labor rates, and part quality.
Can I clear C1264 without repair?
You can clear C1264 temporarily, but the code usually returns until the underlying fault is corrected.