U0131 on 2015-2019 Chevrolet Silverado 2500: Power Steering Communication Loss Fixes

What's Unique About the 2015-2019 Chevrolet SILVERADO 2500

For this generation of Silverado (K2XX platform), code U0131 is very frequently caused by specific, well-documented wiring and grounding issues rather than a failure of the expensive power steering rack or module itself. GM has issued Technical Service Bulletins (TSBs) that point directly to chafed wiring harnesses under the door sill plates (TSB #PIT5457D) and poor ground points, specifically G218 in the driver's footwell (TSB #PIT5405C), as the primary culprits. This platform-specific knowledge is critical, as it directs diagnosis toward simple, often low-cost, electrical repairs before condemning expensive components. Importantly, the Silverado 2500 HD uses a computer-controlled hydraulic power steering system (termed 'Digital Steering Assist' on some models), not the fully electric rack found in the 1500 series, but it is still dependent on the same vulnerable electrical architecture.

Diagnostic Flowchart

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

Symptoms You May Notice

• "Service Power Steering" or "Steering Assist is Reduced Drive with Care" message on the driver information center.
• Complete loss of power steering assist, making the steering wheel very heavy and difficult to turn.
• Warning lights for ABS, StabiliTrak, and steering on the instrument cluster.
• A chime may sound when the warning message appears.
• In some cases, other electrical issues may occur, like a blank instrument panel or radio, due to the instability of the shared ground circuit.

Most Likely Causes

1. Poor Ground Connection at G218 🔴 High Probability As documented in TSB #PIT5405C and its successor #18-NA-161, a dash insulator mat can get trapped under the BCM ground terminal (G218), causing a poor connection. This ground is located in the driver's footwell, often behind the A-pillar trim or near the speaker. The intermittent connection creates network instability that often manifests when electrical load increases, such as when turning the wheel at low speeds.
   How to confirm: Visually inspect ground G218 in the driver's footwell. Remove the 10mm nut and eyelet terminal. Check if the sound-deadening insulation mat is underneath the terminal. Also inspect for paint or weld spatter on the stud that would prevent a clean connection. Clean the terminal eyelet and the body surface with a wire brush or emery paper, and re-secure it tightly.
   Typical fix: Remove the 10mm nut, pull back the ground terminal, and cut away the section of the dash insulator mat that is interfering with the connection. Clean the contact surfaces of the terminal and stud before reinstalling and tightening the nut.
   Est. part cost: $0
2. Damaged Wiring Harness Under Door Sill Plates 🟡 Medium Probability As documented in TSB #PIT5457D, the wiring harness that runs under the driver and passenger door sill plates is susceptible to damage from moisture, corrosion, or chafing. [Bulletin #PIT5457D] This can cause an open or short in the communication circuits for the PSCM, specifically the Communication Enable circuit 5986. Splice J365 under the passenger front sill plate is a known point of failure.
   How to confirm: Remove the driver and passenger side door sill plates and peel back the carpet to visually inspect the wiring harness for any signs of green corrosion, pinched wires, or breaks. Pay close attention to splice points like J365. A multimeter can be used to check for continuity on the affected circuits.
   Typical fix: Repair the damaged section of the wire harness. This involves cutting out the corroded or broken section, splicing in a new piece of wire using weatherproof connectors, and protecting the repair with heat-shrink tubing.
   Est. part cost: $5-$20
3. High-Resistance Negative Battery Cable 🟡 Medium Probability Over time, the main negative battery cable can develop high internal resistance. This can cause a system-wide low voltage condition under load, which can trigger communication codes for sensitive modules like the PSCM. This issue can sometimes be misdiagnosed as a bad ground at G218, as the symptoms are similar.
   How to confirm: Perform a loaded voltage drop test on the negative battery cable as detailed in TSB #18-NA-161. With the fuel system disabled, crank the engine and measure the voltage between the negative battery post and a clean point on the engine block. A reading above 200 mV indicates excessive resistance.
   Typical fix: Replace the entire negative battery cable assembly with a new OEM part. Ensure all connection points at the battery, body, and engine block are clean and tight.
   Est. part cost: $50-$100
4. Failed Power Steering Control Module (PSCM) or Motor ⚪ Low Probability While less common than wiring issues, the internal electronics of the module or motor can fail. A safety recall (#14743) was issued for some 2015 models for a condition that could cause a sudden loss of power steering assist. The official remedy was to replace the power steering assist motor kit, which contains the module.
   How to confirm: This is typically diagnosed by exclusion. If all wiring (power, ground, communication enable circuit, CAN bus), grounds, and fuses are confirmed to be good, and the module still does not communicate, the PSCM itself is the likely culprit.
   Typical fix: Replace the Power Steering Control Module or the entire power steering gear assembly, which often includes the module and motor. The new module will require programming by a dealer or a properly equipped independent shop to work with the vehicle.
   Est. part cost: $500-$1600
5. Blown Fuse ⚪ Low Probability A voltage spike or a short circuit in the power steering system can blow the fuse that supplies power to the Power Steering Control Module, causing it to shut down completely.
   How to confirm: Locate the fuse for the PSCM in the underhood fuse block. This is often a large-amperage (e.g., 80A-100A) fuse, sometimes on a separate block on the positive battery terminal. Pull the fuse and visually inspect if the internal filament is broken or test for continuity with a multimeter.
   Typical fix: Replace the blown fuse with a new one of the exact same amperage rating. If the fuse blows again, a short circuit exists that must be diagnosed and repaired.
   Est. part cost: $5-$15

Diagnosis Steps

1. Read all DTCs from all modules. Note if other modules are also offline, which points to a broader network issue.
2. Check for open recalls, especially safety recall #14743 for 2015 models, which addresses a loss of power steering.
3. Following TSB #PIT5405C / #18-NA-161, locate and inspect ground G218 in the driver's footwell. Remove the 10mm nut and check for a trapped insulation mat. Clean the terminal and stud, then re-secure tightly.
4. Following TSB #PIT5457D, remove the driver and passenger door sill plates and inspect the wiring harness for corrosion, damage, or broken wires, paying special attention to the Communication Enable circuit (5986).
5. Perform a loaded voltage drop test on the negative battery cable as per TSB #18-NA-161. A reading over 200mV while cranking indicates a bad cable that needs replacement.
6. Inspect the fuses related to the Power Steering Control Module in the underhood fuse block.
7. With the battery disconnected, measure the resistance between Pin 6 (CAN_H) and Pin 14 (CAN_L) at the OBD-II port. A healthy network should read approximately 60 Ohms. Readings of 120 Ohms or OL (Open Loop) indicate a break in the CAN bus wiring or a missing termination resistor.
8. If wiring and grounds are good, inspect the electrical connectors at the power steering rack/PSCM (like X183/X133) for corrosion, damage, or loose pins. Test for battery voltage and good ground directly at the PSCM connector to ensure the module is receiving power.
9. If all power, ground, and communication network tests pass, the Power Steering Control Module is the likely point of failure. Replacement requires programming with GM's SPS software.

Parts You'll Likely Need

• Power Steering Rack and Pinion Assembly (with Motor/Module) (OEM #ACDelco 19417063 (Remanufactured)) — This is the part to replace if all wiring and ground issues have been ruled out. The module is integrated with the power steering rack and motor.
  Trusted brands: ACDelco (GM Genuine Parts)
  OEM price range: $1500-$1700
  Aftermarket price range: $800-$1200
• Negative Battery Cable — A common failure point that causes high resistance and system-wide voltage drops, triggering communication codes.
  Trusted brands: ACDelco
  OEM price range: $70
  Aftermarket price range: $40
• Wiring Repair Supplies — Often, the fix is simply repairing a corroded or broken wire in the harness under the sill plates as per TSB #PIT5457D.
  OEM price range: $5-$20
  Aftermarket price range: $5-$20

Related Codes That Often Appear With This One

• U0077 — Indicates a general communication bus issue, often set alongside specific module communication loss codes like U0131. [Bulletin #PIT5457D]
• U0121 — Lost Communication with Anti-Lock Brake System (ABS) Control Module. Often appears with U0131 due to shared wiring harnesses (under the sill plates) and the systems' interdependence. [Bulletin #PIT5457D]
• U0126 — Lost Communication With Steering Angle Sensor Module. Often appears with U0131 due to shared wiring harnesses and the systems' interdependence. [Bulletin #PIT5457D]
• U0415 — Invalid Data Received From Anti-Lock Brake System (ABS) Control Module. This can be a consequence of the communication breakdown that also triggers U0131. [Bulletin #PIT5457D]

Technical Service Bulletins (TSBs) & Recalls

• PIT5457D
• PIT5405C
• 18-NA-161
• 14743

Platform-Specific Known Issues

• TSB #PIT5457D: Specifically calls out inspecting the wire harness under the driver and passenger sill plates for opens or damage to the Communication Enable circuit (5986) when U0131 is present.
• TSB #PIT5405C & #18-NA-161: Points to a poor BCM ground at location G218 (driver's footwell) due to an trapped dash insulator mat as a primary cause for a host of electrical issues, including U0131.
• Safety Recall #14743: Issued for certain 2015 models for a sudden loss of power steering assist. The fix was to replace the power steering assist motor kit. The recall notes that DTC U0131 may be set as a result of this condition.

Mechanic-Grade Diagnostic Values

• CAN Bus Network Resistance — expected: ~60 Ohms. Failure: A reading of ~120 Ohms indicates one of the two terminating resistors is missing or the circuit is open. A reading of ~40 Ohms or less suggests an extra terminating resistor or a short between the CAN lines.
• Negative Battery Cable Voltage Drop (Loaded) — expected: Less than 200 mV (0.2 V). Failure: A reading above 200 mV while cranking the engine indicates excessive internal resistance in the cable, requiring replacement.
• Positive Battery Cable Voltage Drop (Loaded) — expected: Less than 100 mV (0.1 V). Failure: A reading above 100 mV while cranking the engine indicates excessive internal resistance in the cable, requiring replacement.
• CAN Bus Voltage (Key-On, Engine-Off) — expected: CAN High and CAN Low should both read approximately 2.5V relative to ground.. Failure: Significant deviation from 2.5V on either line suggests a bus fault. CAN High should be slightly above 2.5V (e.g., 2.6V) and CAN Low slightly below (e.g., 2.4V) during communication.

Scan Tool Commands That Help

• GM GDS2 / Tech2Win with SPS (Service Programming System): Power Steering Control Module - Programming — This function must be performed after installing a new Power Steering Control Module to load the correct vehicle-specific software onto the module.
• GM GDS2 / Tech2Win with SPS (Service Programming System): Power Steering Control Module - Setup — This is used after programming a new module to configure it to the vehicle's specific options and perform necessary calibrations.
• GM GDS2 / Tech2Win: Special Functions (e.g., Steering Angle Sensor Centering, Software Endstop Learn) — These calibrations are required after the PSCM setup is complete to ensure proper operation of the steering system and related safety systems like StabiliTrak.

Wiring & Ground Locations

• G218 — In the driver's side footwell, behind the A-pillar kick panel, often near the speaker.. This is a primary ground point for the Body Control Module (BCM). A poor connection here (often due to a trapped insulation mat) causes widespread network instability that frequently logs a U0131 code.
• Sill Plate Harness (Circuit 5986) — Runs under the driver and passenger side door sill plates, beneath the carpet. [Bulletin #PIT5457D]. This harness contains the Communication Enable circuit (5986) for the PSCM. It is prone to moisture damage, corrosion, and chafing, which can cause an open circuit and prevent the PSCM from communicating.
• X183 / X133 — The main 2-way power and ground connector at the power steering rack/motor assembly.. A loose connection or corrosion at this main connector can cut power to the PSCM, causing it to go offline and trigger a U0131 code. TSB #PIT5405C specifically calls for inspecting this connector.
• DLC (OBD-II Port) Pins 6 & 14 — Under the driver's side dashboard.. These are the High-Speed CAN bus terminals (CAN_H and CAN_L). They provide a direct access point for testing the electrical integrity (resistance, voltage) of the entire communication network that the PSCM relies on.

Real Owner Repair Stories

• Reddit user comment in r/Chevy (2016 Silverado 1500 (K2XX Platform sibling)) — Dash goes black, steering locks up, StabiliTrak message appears randomly.
  ❌ Tried (didn't work) Took it to the dealership for a brake system recall, but the problem started after that.
  ✅ What actually fixed it The issue was identified as a bad negative battery cable, a known issue documented in TSB #18-NA-161. The fix involves performing a loaded voltage drop test and replacing the cable if it exceeds 200mV.
• YouTube comment on 'G218 Ground Issue Fix' video (2014-2018 GM Truck (specific model not stated)) — Unspecified electrical issues consistent with the G218 ground fault.
  ❌ Tried (didn't work) Spent hours searching Google for a solution.
  ✅ What actually fixed it Following the video's instructions to access and clean the G218 ground terminal in the driver's footwell completely fixed the truck's issues in 30 minutes.

"I Checked Everything" — The Actual Cause

• In cases where grounds and wiring harnesses appear visually intact and test okay for simple continuity, the fault can be hidden. Technicians have found that weld spatter on a ground stud or glue from heat-shrink tubing on a ground eyelet can prevent a solid connection that only fails under electrical load. The fix is to physically disassemble the ground, grind the stud surface flat, and scrape the eyelet clean.
• A similar fault pattern can occur within the underhood fuse block (Power Distribution Center). Even if the main PSCM fuse tests good, high resistance can develop in the internal connections of the fuse block itself. This can be diagnosed by measuring voltage directly at the fuse terminals while the system is under load and observing a significant drop, indicating the fuse block itself needs replacement.

OEM Part Supersession History

• Original Power Steering Assist Motor Kit on 2015 models → New Power Steering Assist Motor Kit — A defect in the original EPS module could cause a sudden loss of power steering assist.
  Heads up: This was part of GM Safety Recall #14743. Vehicles under this recall required the physical replacement of the motor kit, not just a software update.

Model Year Variations Within This Range

• 2015: The 2015 model year was subject to two distinct steering-related actions. Recall #14743 required the replacement of the power steering assist motor kit due to a potential for sudden failure. A separate recall involved a software update to the EPS module to prevent a momentary loss and sudden return of steering assist.
• 2015-2019: Unlike the Silverado 1500 which uses a fully Electric Power Steering (EPS) rack, the 2500/3500 HD models use a hydraulic power steering system, some with 'Digital Steering Assist' (a computer-controlled hydraulic variable-assist). While the mechanical components differ, the Power Steering Control Module (PSCM) that controls it is still vulnerable to the same electrical and network faults as the rest of the K2XX platform, such as the G218 ground and sill plate wiring issues.