U0131 on 2015-2017 Chevrolet Silverado: Power Steering Communication Loss Fixes

What's Unique About the 2015-2017 Chevrolet SILVERADO

For this generation of Silverado and its K2XX platform siblings (GMC Sierra, Tahoe, Suburban, Yukon, Escalade), code U0131 is very strongly linked to specific, well-documented electrical flaws rather than a failed power steering rack. General Motors has issued multiple Technical Service Bulletins (TSBs) that point directly to a poor ground connection (G218) and chafed wiring harnesses under the door sill plates as the primary culprits. This platform-specific knowledge is critical, as it directs diagnosis toward simple, low-cost electrical repairs instead of an immediate, expensive component replacement.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Complete loss of power steering, making the wheel very heavy to turn
• "Service Power Steering" or "Steering Assist is Reduced Drive With Care" message on the instrument cluster
• "Service Stabilitrak" message may appear
• Steering wheel jerks or kicks back when turning, especially at low speeds.
• Instrument panel (IPC), radio, or HVAC displays may go blank or flicker intermittently.
• Headlights and dash lights may flicker.
• Door locks may cycle randomly or alarm may sound when locking doors.

Most Likely Causes

1. Poor Ground at G218 🔴 High Probability As documented in TSB #PIT5405C and its successor #18-NA-161, the dash insulator mat is often trapped between the ground eyelet and the body stud during factory assembly. This creates a high-resistance connection for the Body Control Module (BCM), leading to widespread communication faults, including U0131.
   How to confirm: Visually inspect the G218 ground stud, located behind the driver's side dash end cap/kick panel, near the A-pillar and hood release. Check if the foam insulation is caught under the 10mm ground nut. 🎬 Watch this step-by-step guide to fixing the G218 ground issue. A loose nut or corrosion can also be the cause.
   Typical fix: Disconnect the battery. Remove the 10mm nut, pull the ground terminal eyelet off the stud, and trim away the interfering insulation mat. Clean the eyelet and body surface with a wire brush or emery paper, and re-secure the ground nut tightly.
   Est. part cost: $0-$5
2. Damaged Wiring Under Sill Plates 🔴 High Probability TSB #PIT5457D points out that the Communication Enable circuit (wire 5986, typically a yellow wire) is routed in the harness under the driver and passenger door sill plates. This area is prone to moisture, corrosion, and physical damage from getting pinched or chafed, leading to an open or shorted wire that prevents the PSCM from 'waking up'.
   How to confirm: Remove the sill plates and inspect the wiring harness for chafing, corrosion, or broken wires. With a multimeter, check for ~12V on the Communication Enable circuit (5986) at the PSCM connector when the key is on. TSB #PIT5457D suggests load testing this circuit with a small 194 bulb, as a simple voltage check can be misleading.
   Typical fix: Repair the damaged section of the wire using a butt connector with heat shrink to protect it from future moisture. Pay special attention to splice J365 under the passenger sill plate, which is a known failure point.
   Est. part cost: $5-$20
3. Weak or Faulty Battery / Loose Connections 🟡 Medium Probability Low system voltage can cause unpredictable communication errors between modules. The electric power steering is a high-load system, and voltage drops during steering maneuvers can cause the PSCM to drop offline. TSB #18-NA-161 also points to high resistance in the main battery cables themselves as a potential cause.
   How to confirm: Test the battery with a digital load tester (like a GR8 tester as specified by GM); a simple voltage check is not sufficient. Ensure battery voltage is above 12.4V with the engine off. Perform a voltage drop test on the positive and negative battery cables per TSB #18-NA-161. Inspect all battery terminals for tightness and corrosion at the battery, fuse block, and engine block.
   Typical fix: Replace the battery if it fails a load test. Clean and tighten all battery cable connections. If a voltage drop test fails, replace the faulty negative or positive battery cable assembly.
   Est. part cost: $150-$300

Rare But Worth Checking

• Failed Power Steering Control Module (PSCM): While possible, outright failure of the module is much less common than the wiring and ground issues. The PSCM is integrated into the electric power steering motor on the steering rack. This should be considered a last resort only after all other electrical power, ground, and communication circuit causes have been meticulously ruled out. Replacement requires programming with GM-specific software.
🎬 Watch a professional technician program a new power steering control module.
• Shorted Starter Solenoid B+ Cable: TSB #PIT5405C and #18-NA-161 note that a mis-installed or loose starter heat shield can contact the B+ battery cable terminal on the starter, causing a short to ground. This can lead to widespread electrical issues and voltage drops that trigger U0131, especially when turning the wheel at low speeds.
• Loose Power/Ground Connector at Steering Rack: TSB #PIT5405C advises checking the main 2-pin power and ground connector for the power steering rack itself (connector X183 or X133). Terminals can become loose, backed out, or corroded, cutting power to the entire assembly.

Diagnosis Steps

1. Perform a full vehicle scan with a tool that can read codes from all modules. Note all present U-codes and which modules are reporting them.
2. Check the battery and charging system. Ensure the battery is fully charged and passes a load test. Verify terminal connections are clean and tight. Perform a voltage drop test on the main battery cables per TSB 18-NA-161.
3. Inspect the G218 ground connection. Remove the driver's side dash end panel, locate the ground stud near the A-pillar, remove the 10mm nut, and check for trapped insulation, looseness, or corrosion as per TSB #PIT5405C. Clean and secure the connection.
4. Inspect the wiring harness under the driver and passenger sill plates for damage, corrosion, or opens, specifically looking for issues with the Communication Enable circuit 5986 (yellow wire) as per TSB #PIT5457D.
5. Check the main power and ground connections for the power steering rack itself at the 2-pin connector (X183 or X133). Ensure terminals are clean, tight, and not backed out.
6. Inspect the starter solenoid B+ cable for any signs of shorting against its heat shield.
7. If all wiring, grounds, and power sources are confirmed good, the final step is to suspect a failed Power Steering Control Module (PSCM), which is part of the steering rack assembly. This requires professional confirmation and programming upon replacement.

Parts You'll Likely Need

• Wire Repair Supplies — To fix the most common causes, which are broken or corroded wires under the sill plates or a bad ground connection.
  Trusted brands: 3M
  OEM price range: $5-$25
  Aftermarket price range: $5-$25
• Power Steering Control Module / Steering Rack Assembly (OEM #84446361) — This is replaced as a last resort after all wiring and ground issues have been ruled out. The module is integrated with the electric power steering rack. Part number 84446361 supersedes 84346954, 84228166, 84073904, 84059834, and 23412215.
  Trusted brands: ACDelco, GM Genuine
  OEM price range: $450-$730
  Aftermarket price range: $400-$600

Related Codes That Often Appear With This One

• U0121 — Lost Communication with Electronic Brake Control Module (EBCM). This often appears with U0131 because both modules can be affected by the same wiring harness (under sill plates) and ground (G218) issues, as cited in TSBs PIT5457D and PIT5405C.
• U0077 — Lost Communication With Body Control Module 'B'. This is another code cited in TSB #PIT5457D related to the same communication enable circuit (5986) fault under the sill plates.
• U0140 — Lost Communication With Body Control Module (BCM). This can be set if the G218 ground, which is the primary ground for the BCM, is compromised, causing the BCM itself to become unstable.

Technical Service Bulletins (TSBs) & Recalls

• PIT5457D: Addresses loss of communication with multiple modules (PSCM, EBCM, etc.) due to a damaged Communication Enable circuit (5986) in the wire harness under the driver/passenger sill plates.
• PIT5405C / 18-NA-161: Cites a long list of electrical gremlins (including U0131 and loss of power steering) resulting from a poor BCM ground at G218, a shorted starter B+ cable, or high-resistance battery cables.

Platform-Specific Known Issues

• TSB #PIT5405C (and its successor 18-NA-161) directly links U0131 to a poor BCM ground at location G218, often caused by a dash insulator mat being trapped under the ground nut during assembly.
• TSB #PIT5457D identifies an open or high resistance in the Communication Enable circuit (5986) under the door sill plates as a cause for loss of communication with the PSCM, setting code U0131.
• A Reddit user on r/mechanicadvice reported that after the G218 ground fix only provided a temporary solution, the ultimate culprit was a faulty negative battery cable with high internal resistance. Replacing the cable resolved the issue permanently.

Mechanic-Grade Diagnostic Values

• High-Speed CAN Bus Network Resistance — expected: ~60 Ω (Ohms) when measured between Pin 6 and Pin 14 of the Data Link Connector (DLC) with the battery disconnected.. Failure: A reading of ~120 Ω indicates an open circuit or a missing terminating resistor. A reading near 0 Ω indicates a short between the CAN High and Low wires.
• Communication Enable Circuit (Circuit 5986) Voltage — expected: Approximately 12V with the key in ACC, ON, or START. Must maintain at least 11V when load-tested with a 194 bulb (which draws ~250mA).. Failure: Low or no voltage indicates an open, short, or high resistance in the circuit. Voltage dropping below 11V under a light load confirms high resistance that a simple multimeter check might miss.
• High-Speed CAN Bus Voltage (Key On, Engine Off) — expected: CAN High (Pin 6 at DLC) and CAN Low (Pin 14 at DLC) should both rest at approximately 2.5V.. Failure: Voltages stuck high, low, or at battery/ground potential indicate a shorted wire or a faulty module dragging down the bus.
• Negative Battery Cable Voltage Drop — expected: Less than 200 mV while cranking the engine (fuel system disabled).. Failure: A reading above 200 mV indicates high internal resistance in the cable, requiring replacement.

Scan Tool Commands That Help

• GM GDS2 (Global Diagnostic System 2): Power Steering Control Module Programming & Setup — This is required after replacing the PSCM or the entire steering rack. The process involves two steps: 'Programming' to load the correct software and 'Setup' to calibrate the new module to the vehicle's specific options. Failure to perform both steps will result in continued warnings and codes.
• Professional Scan Tool (e.g., Autel): Read All Modules / Network Scan — When diagnosing U0131, it's critical to see which other modules are also reporting the communication loss. If only the EBCM and BCM report the code, the fault is likely between them and the PSCM. If many modules report communication loss codes, it points to a more systemic issue like the G218 ground or a battery problem.

Wiring & Ground Locations

• G218 — Behind the driver's side dash end cap/kick panel, near the A-pillar and hood release.. This is the primary ground for the Body Control Module (BCM). When compromised by trapped insulation from the factory, it causes the BCM to malfunction, leading to widespread communication codes, including U0131.
• Splice J365 — In the wiring harness located under the passenger's front door sill plate.. TSB #PIT5457D identifies this as a known failure point for the Communication Enable circuit (5986). Corrosion or a bad connection at this splice will cut the 'wake-up' signal to the PSCM.
• PSCM Connector X183 / X133 — The main 2-pin power and ground connector located on the electric power steering rack assembly itself.. This is the final connection point for the high-amperage power needed by the steering motor. A loose, backed-out, or corroded terminal here will cut all power to the PSCM, causing it to go offline and trigger U0131.
• PSCM Power Fuse — In a hidden fuse block on top of the battery, under the positive terminal cover. Often a large 100A or 175A J-case fuse.. This is the main fuse for the entire electric power steering system. If it blows due to a short circuit, the PSCM will lose all power. Many owners and technicians are unaware of this fuse location.

Real Owner Repair Stories

• YouTube user 'Best Car Fixes' (2017 Chevrolet Silverado) — Loss of power steering, 'Service Power Steering' message, multiple communication codes including U0131 in the EBCM.
  ❌ Tried (didn't work) Clearing codes (code immediately returned), Checking fuses in the main underhood fuse box.
  ✅ What actually fixed it The vehicle had been in a front-end accident. The technician found that the main power and ground connector on the power steering rack itself was damaged and not making a proper connection. After repairing the connector, communication was restored and the power steering functioned correctly.
• MHH Auto forum user 'steverucano' (2014 Chevrolet Silverado) — No power steering, no communication with PSCM using GDS2, steering angle sensor failing to initialize.
  ❌ Tried (didn't work) Verified 12V power and ground at the PSCM main connector., Load tested the 12V communication enable wire (held 11.5V with a test light)., Checked CAN bus voltages (all appeared normal at ~1.5V or ~2.5V)., Replaced the PSCM.
  ✅ What actually fixed it The user reported that even after replacing the PSCM and verifying all power, ground, and communication enable circuits, the module would still not communicate. The thread ends without a definitive fix, highlighting a scenario where all common TSB-related fixes do not resolve the issue, pointing towards a deeper, un-diagnosed network or wiring harness problem.

OEM Part Supersession History

• 23412215, 84059834, 84073904, 84228166, 84346954 → 84446361 — Standard part evolution, likely for improved reliability or manufacturing changes.
  Heads up: The listed part numbers are for the PSCM module itself, which is integrated with the steering rack. While physically interchangeable, a replacement module/rack requires programming with GM's GDS2 software to match the vehicle's VIN and options.