U0428 on 2015-2019 GMC Sierra 2500: Invalid Steering Angle Data Causes & Fixes

What's Unique About the 2015-2019 Gmc SIERRA 2500

On this generation of GM trucks (K2XX platform), U0428 is strongly linked to specific, well-documented electrical vulnerabilities rather than simple component failure. Manufacturer TSBs consistently point technicians toward three main culprits: a poor ground connection at location G218 under the dash (TSB PIT5405C), damaged communication wires in the harnesses that run under the driver and passenger sill plates (TSB PIT5457D), and a software glitch in the Power Steering Control Module (TSB 20-NA-113). These issues are far more common than the steering angle sensor itself failing and should always be investigated first.

Diagnostic Flowchart

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

Symptoms You May Notice

• "Service StabiliTrak" message on the instrument panel.
• "Steering Assist is Reduced Drive with Care" message.
• ABS and Traction Control warning lights illuminated.
• Intermittent loss of, or reduced, power steering assist, making the wheel feel heavy.
• Steering wheel jerks or kicks back when turning at low speeds.
• In rare cases, the instrument panel, radio, or HVAC may go blank or the engine may stall when turning, especially if the G218 ground is the cause.
🎬 See how these specific codes affect your truck's steering
• Backup camera guidelines may disappear.
• Cruise control may be inoperative.

Most Likely Causes

1. Poor Body Control Module (BCM) Ground (G218) 🔴 High Probability As documented in TSB #PIT5405C, the dash insulator mat can get trapped between the ground eyelet and the body stud under the driver's side dash during assembly. This prevents a solid metal-to-metal connection, causing high resistance and a host of electrical issues that are often triggered by the increased electrical load of the power steering pump during low-speed turns.
   How to confirm: Visually inspect the G218 ground stud, located on the A-pillar support frame, deep inside the driver's side dash, often near the speaker. Access requires removing the side dash panel and possibly the A-pillar trim. Check for the black foam insulation mat being trapped under the 10mm ground nut and eyelet.
   Typical fix: Disconnect the battery. Remove the 10mm ground nut. Cut away or pull back the interfering dash insulator mat. Use a wire brush or sandpaper to clean the ground eyelet, the stud, and the chassis surface to bare metal. Re-secure the nut tightly.
   Est. part cost: $0-$5
2. Damaged Wiring in Sill Plate Harness 🔴 High Probability TSB #PIT5457D specifically calls out that the wiring harnesses running under the driver and passenger door sill plates are susceptible to moisture intrusion from wet shoes, clogged sunroof drains, or poor door seals. This leads to corrosion (often seen as green or white powder), open circuits, or damaged wires, particularly on the low-voltage communication enable circuit (Circuit 5986).
   How to confirm: Remove the driver and passenger sill plates and peel back the carpet to gain access to the wiring channel. Carefully unwrap the harness tape and inspect the bundled wires, especially any twisted pairs, for signs of corrosion, chafing, or breaks.
   Typical fix: Repair any damaged sections of wire using solder and heat-shrink tubing or appropriate sealed, weatherproof butt connectors. If corrosion is extensive, a portion of the harness may need to be replaced. Ensure the area is dry and re-wrap the harness with high-quality electrical tape (like Tesa tape) for future protection.
   Est. part cost: $10-$50
3. Power Steering Control Module (PSCM) Calibration Error 🟡 Medium Probability GM issued TSB #20-NA-113 because of a software glitch where the PSCM fails to transition DTCs to 'history' after the triggering event (like a low battery) is resolved. The code remains 'current' and the 'Service Steering' message appears on every startup, even though no active fault exists. This can lead to misdiagnosis and unnecessary parts replacement.
   How to confirm: If the U0428 code can be cleared with a scan tool but returns immediately on the next key cycle without the vehicle moving, this software issue is highly likely. This is especially true if the vehicle recently had a dead or replaced battery.
   Typical fix: The PSCM must be reprogrammed with the latest software calibration by a dealer or a qualified shop with a J2534 pass-thru device and access to GM's TIS2WEB service.
   Est. part cost: $0 (parts), $150-$300 (labor)
4. Failing Steering Angle Sensor (SAS) ⚪ Low Probability → Shop Steering Angle Sensor
   How to confirm: If and only if all wiring, ground, and software issues have been definitively ruled out, use a professional scan tool to monitor the live data from the steering angle sensor. The angle should change smoothly and logically as you turn the wheel lock-to-lock. If the value is stuck, jumps erratically, or shows 'invalid', the sensor is likely faulty.
   Typical fix: Replace the steering angle sensor, which is typically located in the steering column behind the clock spring. 🎬 Watch: How to locate and remove the steering angle sensor After replacement, the new sensor must be calibrated using a compatible scan tool.
   Est. part cost: $75-$200

Rare But Worth Checking

• Failing Electronic Brake Control Module (EBCM): The EBCM is a primary user of the steering angle data for StabiliTrak. While uncommon, an internal failure of the EBCM could cause it to misinterpret a valid signal, setting this code. This should be considered a last resort after all other possibilities are exhausted.
• Weak or Failing Battery: → Shop Vehicle Battery A weak battery can cause low voltage during engine cranking, leading to a cascade of communication codes, including U0428. While this may trigger the PSCM software glitch mentioned above, sometimes simply replacing an old battery and clearing the codes can resolve the issue.

Diagnosis Steps

1. Scan all vehicle modules for DTCs and record them. Note all other communication codes that are present alongside U0428.
2. Begin by inspecting the G218 ground location under the driver's side dash, as per TSB #PIT5405C. Check for trapped insulation, looseness, or corrosion. Disassemble, clean all contact surfaces to bare metal, and tighten securely.
3. Remove the driver and passenger side sill plates and inspect the wiring harnesses for any signs of chafing, breaks, or corrosion, as per TSB #PIT5457D. Pay close attention to splice packs and the communication enable circuit (often a small gauge wire).
4. If wiring and grounds are confirmed good, attempt to clear the codes. If U0428 returns immediately on the next key-on without driving, suspect the PSCM software glitch (TSB 20-NA-113) and seek module reprogramming.
5. If the code only returns while driving, and electrical faults have been ruled out, connect a professional scan tool and view the live data for the Steering Angle Sensor.
6. Turn the steering wheel from lock to lock. The angle reading should be smooth and continuous. If it is frozen, erratic, or reads as invalid, the sensor is the likely culprit.
7. If the sensor is replaced, perform the Steering Angle Sensor calibration/relearn procedure with the scan tool to zero the new sensor and ensure proper function.

Parts You'll Likely Need

• Steering Angle Sensor (OEM #13590209) — This sensor provides the critical steering wheel position data. It is the part to replace ONLY if wiring, grounds, and software are confirmed to be good, but the live data is still erratic or invalid. Note: This part may be superseded by other numbers like 13589991, always verify with VIN.
  Trusted brands: ACDelco, GM Genuine
  OEM price range: $100-$150

Related Codes That Often Appear With This One

• U0121 — Lost Communication With Electronic Brake Control Module (EBCM). Often set alongside U0428 due to the G218 or sill plate wiring issue.
• U0131 — Lost Communication With Power Steering Control Module (PSCM). Also related to the common wiring and ground faults.
• U0415 — Invalid Data Received From Electronic Brake Control Module (EBCM). Indicates the same network instability.
• C0544 — Steering Wheel Angle Sensor Circuit Malfunction. A more specific circuit code that often accompanies the U0428 communication code.
• C0710 — Steering Wheel Position Sensor Signal. Another related sensor circuit code pointing to the same system.

Technical Service Bulletins (TSBs) & Recalls

• PIT5457D: Communication DTCs set due to damaged wiring in sill plate harness.
• PIT5405A/C: Multiple DTCs, including U0428, set due to poor BCM ground at G218.
• 20-NA-113: Action Required Steering Assist is Reduced message, DTCs stay 'current' due to PSCM calibration error.

Platform-Specific Known Issues

• TSB #PIT5457D: Documents that communication codes, including U0428, can be caused by damaged or corroded wiring in the harnesses located under the door sill plates.
• TSB #PIT5405C: Points to a poor ground at the G218 location as a cause for a long list of DTCs, including U0428. The issue is often caused by the dash insulator mat getting caught under the ground connection.
• TSB #20-NA-113: Details a software error in the Power Steering Control Module (PSCM) that can cause U0428 to remain 'current' after the initial fault (like a low battery) is fixed, requiring a module reprogram.

Mechanic-Grade Diagnostic Values

• Communication Enable Circuit (Circuit 5986) Voltage — expected: Approximately 12 Volts with key in ACC or ON position.. Failure: Low or no voltage indicates an open or high resistance in the circuit, often under the sill plates. The circuit should be able to light a small 194 bulb.
• High-Speed GMLAN Bus Resistance — expected: Approximately 60 Ohms between CAN High and CAN Low pins at the DLC (with battery disconnected).. Failure: A reading of 120 Ohms indicates a missing termination resistor or an open in the bus. A reading significantly lower than 60 Ohms (e.g., 40 Ohms) could indicate an extra termination resistor or a shorted module.
• High-Speed GMLAN Bus Voltage (Key On, Engine Off) — expected: CAN High and CAN Low should both be around 2.5V relative to ground. During communication, CAN High toggles toward 3.5V and CAN Low toggles toward 1.5V.. Failure: Voltages stuck high, low, or at 0V indicate a short to power, short to ground, or an open circuit. A multimeter will show average voltages around 2.7V for CAN High and 2.3V for CAN Low during normal activity.

Scan Tool Commands That Help

• GDS2 (GM Dealer Software): Steering Angle Sensor Calibration / Learn — Required after replacing the steering angle sensor, steering column, performing a wheel alignment, or after any repair that disturbs the steering linkage to zero the sensor's position.
• GDS2 (GM Dealer Software): PSCM Reprogramming — Used to apply the latest software calibration to the Power Steering Control Module to fix the known glitch described in TSB 20-NA-113, where a temporary fault code becomes permanently 'current'.
• GDS2 (GM Dealer Software): Clear All DTCs — This is a critical step before attempting to reprogram a module. If codes cannot be cleared, it indicates a hard fault is still present that must be diagnosed and repaired before a software update can be successful.

Wiring & Ground Locations

• G218 — Located deep inside the driver's side dash on the A-pillar support frame, often behind or near the side dash speaker.. This is the primary ground for the Body Control Module (BCM). As per TSB PIT5405C, sound insulation is often trapped under the ground nut from the factory, causing high resistance that disrupts communication across the vehicle, triggering U0428 and many other codes.
• Circuit 5986 (Communication Enable) — Runs in the wiring harnesses located under the driver and passenger side door sill plates. TSB PIT5457D highlights this circuit as being prone to corrosion and damage from moisture.. This circuit is activated by the BCM to 'wake up' other modules like the PSCM and EBCM for communication. An open or short in this wire prevents those modules from communicating, leading to a host of 'Lost Communication' and 'Invalid Data' codes, including U0428.
• K43 Power Steering Control Module Connector X1 — On the power steering rack itself. This is a 12-pin connector.. This connector contains the GMLAN serial data wires (Pins 4, 6, 11) and the Serial Data Communication Enable wire (Pin 2). A fault at this connector can directly cause code U0428.

Real Owner Repair Stories

• YouTube user 'last call' and others in comments/related videos (2014 Chevrolet Silverado (K2XX Platform-mate)) — Multiple electrical issues, Service StabiliTrak message, instrument panel and radio flashing, engine stalling at low speeds when turning.
  ❌ Tried (didn't work) Initial diagnosis was difficult due to the wide range of intermittent electrical symptoms.
  ✅ What actually fixed it The problem was definitively traced to the G218 ground stud behind the driver's side dash speaker. Sound deadening material was trapped under the ground nut. Cutting away the material and cleaning the connection point permanently resolved the issues.
• Reddit user in r/Silverado (2015 Silverado 1500 with 30k miles (K2XX Platform-mate)) — "Service StabiliTrak" message flashes on the dash, radio and other screens flash, seemed to only happen in the rain when turning right.
  ❌ Tried (didn't work) Owner was initially lost and considering checking wheel bearing sensors.
  ✅ What actually fixed it Another user pointed to the G218 ground issue. The original poster researched the G218 ground fix and confirmed this was the likely solution, as many others had the exact same symptoms fixed by cleaning the ground stud.

OEM Part Supersession History

• 13589991 → 13590209 — Standard part number update/revision by the manufacturer.
  Heads up: No known incompatibility. 13590209 is the current correct service part. Always verify with VIN.

Model Year Variations Within This Range

• 2015-2019: There are no significant variations within the 2015-2019 model years for the GMC Sierra 2500 that affect the diagnosis or common causes of code U0428. The entire range uses the K2XX platform and is susceptible to the same G218 ground and sill plate wiring issues.