C1273 Code: Meaning, Symptoms, Causes & Fix

C1273

Overview

When C1273 appears, the control module has detected abnormal behavior related to Motor # 2 Input Circuit Short to Vbat in ABS/chassis dynamics and brake control.

Symptoms

  • longer braking intervention
  • ABS/traction light on
  • chassis warning indicator

Common causes

  • Broken terminal inside harness affecting motor # 2 input circuit short to vbat
  • Disconnected or loose connector
  • Connector pin damage/corrosion or harness stress near related components

How to diagnose C1273

  1. Confirm C1273 and capture freeze-frame data with a professional scan tool.
  2. Inspect wiring, connectors, and grounds related to motor # 2 input circuit short to vbat for obvious defects.
  3. Use a continuity test from module pin to component to identify opens/high resistance.
  4. Check for related DTCs to identify the root-cause chain before replacing parts.
  5. After repair, clear codes and confirm readiness monitors complete without recurrence.

Severity of code C1273

Moderate: This code is moderate severity: the vehicle may still operate, but fault progression can increase repair cost over time.

Can you drive with C1273?

Most vehicles can be driven short-term with C1273, 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)

  1. Repair obvious wiring/connector faults first to prevent repeat parts replacement.
  2. Address the root fault mode (open) in the motor # 2 input circuit short to vbat circuit/system.
  3. Apply the required relearn/adaptation procedure if specified by service information.
  4. Road-test and verify C1273 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 C1273

  • 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.

C1273 in common vehicles

C1273 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 C1273?

C1273 is commonly set by open faults affecting motor # 2 input circuit short to vbat.

How much does it cost to fix C1273?

For C1273, repair costs are typically $240-$1200 depending on exact root cause, labor rates, and part quality.

Can I clear C1273 without repair?

You can clear C1273 temporarily, but the code usually returns until the underlying fault is corrected.

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