C1244

What Does Code C1244 Mean?

DTC C1244 signifies an issue with the ABS Outlet Valve Coil LR Circuit Short To Battery. This diagnostic trouble code is set by the Anti-lock Braking System (ABS) control module, also known as the Electronic Brake Control Module (EBCM) or integrated into the Hydraulic Control Unit (HCU). The ABS module continuously monitors the electrical circuits of the solenoid valves within the hydraulic unit. Specifically, C1244 indicates that the module has detected an unintended high voltage, equivalent to battery voltage, on the control circuit for the Left Rear (LR) outlet valve solenoid coil. This occurs when the circuit is supposed to be at a lower, controlled voltage or grounded. The presence of battery voltage on this circuit when it should not be means there is an electrical short to a constant power source (battery voltage), which prevents the ABS module from accurately controlling the hydraulic pressure release to the left rear wheel during an ABS event. This critical fault disables the ABS system to prevent uncontrolled braking actions.

Common Symptoms

• ABS Warning Light Illumination: The primary and most common symptom is the constant illumination of the ABS warning light on the instrument cluster.
• Traction Control / Stability Control Light Illumination: Given the interconnectedness of braking systems, the Traction Control System (TCS) and Electronic Stability Program (ESP/ESC/VSC) warning lights may also illuminate.
• Disabled ABS Functionality: The ABS system will be deactivated, meaning the wheels may lock up under hard braking, especially on slippery surfaces.
• Altered Brake Pedal Feel: While less common, some drivers might report a slightly different brake pedal feel due to the compromised system. Normal braking without ABS intervention may still function.

What Causes the Code C1244?

• Damaged Wiring Harness: A common cause is physical damage to the wiring harness leading to the ABS HCU or directly to the LR outlet valve solenoid. This damage (e.g., chafing, cuts, pinching) can cause the wire to short circuit to a positive voltage source (battery voltage).
• Faulty ABS Hydraulic Control Unit (HCU) / Module: An internal short circuit within the ABS module or the integrated solenoid coil for the LR outlet valve can trigger this code. This implies an internal component failure where the solenoid’s coil itself or its driving circuitry is failing.
• Corroded Electrical Connectors: Corrosion at the multi-pin connector for the ABS HCU or the individual solenoid valve connectors can bridge terminals, causing a short to battery voltage.
• Improper Previous Repair or Installation: Errors during previous service work, such as incorrect wiring, improper component installation, or using non-OEM parts, can lead to this diagnostic trouble code.

How to Diagnose and Troubleshoot

Diagnosing C1244 requires careful electrical testing and visual inspection. Always begin with a safe working environment and disconnect the battery if necessary for component removal or extensive wiring inspection.

1. Retrieve All DTCs: Use an OBD-II scanner to read all stored codes. Note any other related ABS, traction control, or engine control module (ECM/PCM) codes, as they might provide additional context. Clear the codes and re-scan to see if C1244 immediately returns.
2. Visual Inspection of Wiring and Connectors:
   • Inspect the entire wiring harness leading from the ABS HCU to the Left Rear wheel area. Pay close attention to areas where the harness passes through firewalls, over sharp edges, or near moving suspension components. Look for signs of chafing, cuts, melting, or rodent damage.
   • Carefully inspect the electrical connectors at the ABS HCU. Disconnect them (if safe to do so) and check for bent pins, corrosion, moisture intrusion, or loose connections.
3. Digital Multimeter (DMM) Testing – Isolating the Short:
   • System Voltage Check: Verify that the vehicle’s battery voltage is within specifications (typically 12.6V-13.8V). Low system voltage can sometimes cause erratic electrical readings.
   • Disconnect ABS HCU Connector: With the ignition OFF, disconnect the main electrical connector(s) from the ABS HCU. This isolates the module from the wiring harness.
   • Voltage Check on Harness Side: Turn the ignition ON (engine OFF). Using a DMM, probe the terminal corresponding to the LR outlet valve coil control circuit on the harness side of the disconnected connector. There should be 0 Volts (or a very low residual voltage). If battery voltage (or close to it) is present, it confirms a short to battery within the wiring harness.
   • Continuity Check on Harness Side: With the ignition OFF and the HCU still disconnected, use the DMM in continuity or resistance mode. Test for continuity between the LR outlet valve control circuit wire (harness side) and a known good ground, and then to a known battery positive source (e.g., the battery positive terminal). There should be no continuity to battery positive. If continuity to battery positive is found, trace and repair the short in the wiring.
   • Internal Solenoid Coil Resistance Test (if accessible): If the HCU has serviceable solenoids, measure the resistance of the LR outlet valve solenoid coil directly. Compare this reading to factory specifications. An out-of-spec reading or an internal short within the solenoid could indicate the HCU is faulty. Note that many modern ABS HCUs have integrated solenoids that cannot be separately tested or replaced.
4. Re-test after Isolation: If the short to battery voltage disappears when the HCU is disconnected (i.e., you measured 0V on the harness side where you previously had B+ with the HCU connected), then the fault is likely internal to the ABS HCU itself, indicating a need for HCU replacement. If the short persists on the harness side, the issue is definitely in the wiring.

Recommended Repairs and Solutions

Based on the diagnostic findings, the following repairs are typically recommended:

• Repair or Replace Damaged Wiring: If the DMM tests confirm a short to battery within the wiring harness, the damaged section of wire must be meticulously located and repaired. Use high-quality, automotive-grade wire, solder connections, and protect them with heat shrink tubing and loom to prevent future damage. Ensure the repaired section is properly routed and secured away from heat sources or moving parts.
• Replace ABS Hydraulic Control Unit (HCU) / Module: If all wiring and external connections are verified good, and the short is determined to be internal to the ABS HCU (or the module integrated within it), the entire ABS HCU will need to be replaced.
  • Brake Bleeding: Replacing the HCU requires careful bleeding of the brake system, often involving specialized procedures (e.g., using a scan tool to cycle the ABS pump and solenoids for a “service bleed”).
  • Module Programming/Calibration: Many new ABS modules require programming, coding, or calibration to the specific vehicle using a factory-level scan tool. Failure to do so can result in continued warning lights or improper system operation.
• Clean Corroded Connectors: If corrosion was found, carefully clean the electrical terminals using electrical contact cleaner and a small brush. Apply dielectric grease to prevent future corrosion before reassembling the connector.
• Perform System Test Drive: After any repair, clear all DTCs from the ABS module and the ECM/PCM. Perform a thorough road test, including several braking events (at safe speeds and locations) that would typically engage the ABS system, to confirm that the code does not return and that ABS functionality is restored.