OBD-II Code U0131: Lost Communication With Power Steering Control Module

What Does U0131 Mean?

U0131 indicates the vehicle's main computer network lost connection to the Power Steering Control Module (PSCM). This module acts as the brain for the electric power steering (EPS) system. When it stops communicating with the Engine Control Module (ECM) or Body Control Module (BCM), the system shuts off power assist as a safety measure. Your steering immediately becomes extremely heavy, and a dashboard warning light illuminates.

Technical definition: Lost Communication With Power Steering Control Module (PSCM). This generic network communication ('U') code triggers when other control modules on the Controller Area Network (CAN) bus fail to receive required data messages from the PSCM for a calibrated timeframe. It points to an electrical data link failure, not a mechanical failure of the steering gear.

Can I Drive With U0131?

No — Do Not Drive. Do not drive the vehicle. Losing power steering assist makes the vehicle extremely heavy to steer, especially at low speeds or during emergency maneuvers. This significantly increases crash risk. While the vehicle remains technically movable for a short distance to a safe location, continued driving places immense physical strain on the driver and severely compromises vehicle control.

Common Causes

• Poor Power or Ground Connection (Very Common) — This is the primary cause. It includes blown high-amperage fuses, a weak battery, corroded terminals, or a bad ground connection. On GM trucks, ground point G218 is a notorious factory defect. On FCA vehicles, weld spatter on ground studs disrupts contact.
• Damaged Wiring Harness or Connectors (Common) — Chafing, corrosion, moisture, or physical impact damages the PSCM wiring harness. Problem areas include harnesses routed under door sill plates (GM), near the battery tray, or close to the exposed steering rack.
• Internal PSCM Failure (Less Common) — The electronic module fails internally from age, heat stress, or voltage spikes. Modern vehicles integrate the PSCM with the electric steering motor or rack assembly, requiring a complete, expensive unit replacement.
• Outdated or Corrupted PSCM Software (Less Common) — A software bug within the PSCM halts communication, often triggered by a battery replacement or voltage fluctuation. Dealerships resolve this by reprogramming the module (e.g., GM TSB #20-NA-113).
• CAN Bus Network Failure (Less Common) — A short or open circuit in the main CAN bus prevents module communication. This failure almost always triggers additional 'U' codes (like U0073) across multiple modules. A failed 120-ohm terminating resistor also disrupts the network.
• Damage from Previous Repairs (Rare) — Recent collision repairs or maintenance inadvertently cause this code. Technicians frequently find pinched PSCM wiring harnesses or disconnected ground wires following bodywork.
• Aftermarket Device Interference (Rare) — Poorly installed OBD-II devices, such as insurance telematics dongles or custom tuners, disrupt the CAN bus network and trigger a flood of communication errors, including U0131.

Symptoms

• Complete Loss of Power Steering Assist — The primary symptom. Steering requires significant physical effort, making the vehicle exceptionally difficult to turn at low speeds or while parking.
• Illuminated EPS Warning Light — An EPS (Electric Power Steering) indicator or a steering wheel icon with an exclamation mark illuminates on the dashboard.
• Cascading Dashboard Warning Lights — Because the steering system shares data with braking and stability controls, warning lights for ABS, Traction Control, or StabiliTrak frequently illuminate simultaneously.
• Illuminated Check Engine Light (MIL) — The main Malfunction Indicator Lamp turns on to alert the driver of the stored U0131 diagnostic trouble code.
• Intermittent Loss of Electronic Features — If a broader network or grounding issue causes the code, drivers experience seemingly unrelated problems like blank instrument panels or unexpectedly cycling door locks.

Diagnostic Flowchart

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

Common Fixes & Costs

• Replace the Vehicle Battery — Parts: $150-$300, Labor: $50-$100, ~0.5 hr book time (DIY)
• Replace a Blown High-Amperage Fuse — Parts: $5-$25, Labor: $0-$50, ~0.2 hr book time (DIY)
• Repair Wiring or Clean Ground Connections — Parts: $5-$50, Labor: $150-$500, ~1.5 hr book time (Intermediate)
• Reprogram the PSCM — Parts: $0, Labor: $125-$250, ~1.0 hr book time (Professional)
• Replace the Power Steering Rack Assembly — Parts: $800-$2800, Labor: $300-$800, ~4.5 hr book time (Professional)
  2014-2016 Chevrolet Silverado/GMC Sierra 1500: OEM {'part_number': '23271566', 'brand': 'ACDelco GM Genuine'} (Alt: {"part_number": "203-0166ECQ", "brand": "Carquest Premium (Remanufactured)"}, {"part_number": "N203-0166", "brand": "BBB Industries (New)"})
  2011-2014 Ford F-150 (with EPAS): OEM {'part_number': 'BL3Z3504FE', 'brand': 'Ford Motorcraft'} (Alt: {"part_number": "601-900", "brand": "Dorman OE Fix (New, includes programmer)"}, {"part_number": "22-2121", "brand": "Cardone (Remanufactured)"})
  2016 Jeep Grand Cherokee: OEM {'part_number': '68212044AC', 'brand': 'Mopar'} (Alt: {"part_number": "201-0137E", "brand": "MasterPro (Remanufactured)"})

Used vs. New Parts: Buying Guide

When a used part is worth it: Buying a used Electric Power Steering Rack from a salvage yard is highly discouraged due to safety risks and programming requirements. A professionally remanufactured unit is the most cost-effective alternative to new.

Donor-vehicle mileage cap: roughly under 40000 miles for the part to have meaningful remaining life.

Donor quality checklist:

• Choose a reputable remanufacturer offering a strong warranty.
• Ensure the part number matches EXACTLY, including dealer-verified superseded numbers.
• If buying used against advice, ensure the donor vehicle matches perfectly and avoided front-end collisions.

Decision logic:

• If The fault is confirmed as an internal PSCM or rack assembly failure. → Install a new OEM or high-quality remanufactured unit.
• If Budget is constrained and the vehicle has high mileage. → A remanufactured unit offers the best balance of cost and reliability.
• If The replacement part requires programming. → Factor in $125-$250 for dealer programming, or purchase an aftermarket unit that includes a programmer.

Warranty tradeoff: Salvage yard parts offer 30-90 day warranties. Remanufactured parts provide 1-year to limited lifetime warranties. New OEM parts carry 1-2 year warranties.

Worst-case if a used part fails: $500 - $1000 in wasted labor and alignment costs if a faulty used rack is installed.

What Happens If You Wait — Timeline

1. First Occurrence: An intermittent U0131 code sets due to a temporary voltage drop during a cold crank. The warning light flashes but clears on the next startup. (Added cost: $0)
2. Weeks to Months: The underlying electrical issue worsens. The code sets weekly. Power steering fails to initialize at startup but restores after restarting the car. (Added cost: $150-$250 (Towing cost if it fails permanently).)
3. Months: The fault becomes a 'hard fault.' The code sets instantly on startup and cannot be cleared. Power steering assist is permanently lost. (Added cost: $250-$700 (Cost of diagnosis and electrical repair, plus towing).)
4. 6+ Months of Inaction: A shop replaces the expensive steering rack without fixing the root electrical cause. The problem returns immediately. A persistent short in the CAN bus wiring stresses transceivers in other modules. (Added cost: $1500-$4000+ (Cost of a wasted steering rack replacement and complex diagnostics).)

Cost of Not Fixing It

• Immediate: Extreme safety risk. The vehicle is exceptionally difficult to steer, dramatically increasing crash risk. (Added cost: Cost of an accident, potentially thousands of dollars.)
• Short-Term (Days to Weeks): Complete loss of vehicle use due to the safety hazard. No additional component damage is likely. (Added cost: Cost of towing and alternative transportation.)
• Long-Term (Months): Ignoring a wiring issue allows moisture to cause further corrosion, damaging nearby circuits and turning a simple repair into a multi-module failure. (Added cost: $500 - $2000+ if a wiring fault cascades into module failure.)

Diagnosis Steps

1. Perform a Full-Module Network Scan
   Use a professional OBD-II scanner to perform a full network scan of all modules (BCM, ABS, TCM). Do not use a basic engine code reader. The absence of the PSCM on the scan tool's topology map confirms it is offline.
   Tools: Professional OBD-II Scanner (Beginner)
2. Test the Battery and Inspect High-Amperage Fuses
   Inspect all power steering fuses, including high-amperage 'mega' fuses on the positive battery terminal. Perform a full battery load test. A healthy resting battery must exceed 12.4 volts, and the alternator must charge between 13.7 and 14.7 volts.
   Tools: Digital Multimeter, Battery Load Tester, Fuse Puller (Beginner)
3. Inspect the PSCM Wiring Harness and Connectors
   Locate the PSCM (often integrated into the steering rack). Meticulously inspect its electrical connectors for corrosion, moisture, or backed-out pins. Trace the wiring harness for chafing or rodent damage, especially near the battery tray and door sill plates.
   Tools: Flashlight, Inspection Mirror (Intermediate)
4. Perform a Voltage Drop Test on the Ground Circuit
   Connect the multimeter's negative lead to the negative battery post and the positive lead to the PSCM ground pin. With the ignition on, a reading above 200 millivolts (0.2 volts) indicates excessive resistance in the ground circuit requiring repair.
   Tools: Digital Multimeter, Vehicle-specific wiring diagram (Advanced)
5. Verify Power Feed to the PSCM
   Back-probe the PSCM connector to verify it receives full battery voltage on the correct pins. The voltage must remain within 0.5 volts of the actual battery voltage. A significant drop indicates a failing power supply wire or blown fuse.
   Tools: Digital Multimeter, Back-probe leads, Wiring diagram (Advanced)
6. Test CAN Bus Network Resistance
   With the key off and battery disconnected for one minute, measure resistance between Pin 6 (CAN High) and Pin 14 (CAN Low) at the OBD-II port. A healthy network reads 60 ohms (± 5 ohms). A 120-ohm reading indicates an open circuit; 0 ohms indicates a short.
   Tools: Digital Multimeter (Advanced)
7. Isolate the Faulty Module
   If CAN bus resistance reads 120 ohms or 0 ohms, unplug network modules one by one, starting with the PSCM. If resistance returns to 60 ohms after unplugging a specific module, you have identified the source of the network failure.
   Tools: Digital Multimeter, Wiring diagram (Advanced)
8. Analyze the CAN Bus Signal (Oscilloscope)
   Connect oscilloscope probes to CAN High and CAN Low. A healthy signal shows a mirroring square wave pattern. CAN High toggles between 2.5V and 3.5V, while CAN Low toggles between 2.5V and 1.5V. Flat lines or excessive noise indicate shorts or interference.
   Tools: Oscilloscope, Back-probe leads (Professional)

When This Code Triggers (Freeze-Frame Conditions)

• Ignition Status: ON (The code sets within seconds of turning the ignition on as modules perform a network check-in.)
• Battery Voltage: 10.5 - 11.8V (During engine cranking, a weak battery causes a voltage drop sufficient to make modules lose communication.)
• Vehicle Speed: 0 mph (Instances frequently occur at startup, before the vehicle moves.)
• Time Since Engine Start: < 5 seconds (The supervising module expects a message from the PSCM within a strict time window after key-on.)

Related Codes

• U0073 — Indicates 'Control Module Communication Bus A Off', signaling a major fault on the main CAN network. If paired with U0131, the problem is a network-wide issue (bad ground, wiring short) rather than an isolated PSCM failure.
• U0140 — Means 'Lost Communication With Body Control Module (BCM)'. The BCM acts as a gateway and shares grounding points. If present with U0131, suspect a shared ground failure (like GM's G218) or a wiring issue near the BCM.
• U0121 — Indicates 'Lost Communication With Anti-Lock Brake System (ABS) Control Module'. Seeing U0121 and U0131 together strongly suggests a CAN bus wiring fault located where harnesses for both modules run, such as under a door sill plate.
• U0420 — Means 'Invalid Data Received From Power Steering Control Module'. The module remains on the network, but sends corrupt data. This precedes a full failure (U0131) or indicates an internal PSCM software fault.

Climate & Environmental Factors

• Cold Weather: Extreme cold exposes intermittent electrical connections that contract, leading to communication loss. Low temperatures also reduce battery efficiency, triggering voltage-sensitive modules to fail.
• High Humidity & Road Salt: In regions with heavy road salt use, corrosion accelerates U0131 faults. Moisture and salt wick into connectors and ground points, causing high resistance. Exposed steering rack connectors are highly vulnerable.

How to Talk to a Mechanic About This Code

Say this: "I have a U0131 code and lost power steering. Before quoting a steering rack replacement, please perform a full network scan to verify module communication and test the power and ground circuits to the Power Steering Control Module. Check for any manufacturer TSBs regarding grounds or wiring."

This signals you understand the most common causes are electrical faults, not a failed steering rack. It directs the technician to perform logical diagnostics first.

Avoid saying:

• My power steering is out, I think I need a new rack.
• Just fix the U0131 code.
• My steering warning light is on, can you check it out?

Questions to ask before authorizing the repair:

• Did the Power Steering Control Module show up on the network scan?
• What was the result of the voltage drop test on the PSCM's power and ground wires?
• Did you check the resistance of the CAN bus at the OBD-II port? What was the reading?
• If recommending a steering rack replacement, have you ruled out the wiring harness and connectors?
• Does the replacement part require programming, and is that included in the quote?

Where to Take It: Dealer vs Independent vs Chain

• Dealer: Recommended if a TSB points to a software update or for complex, hard-to-find network faults.
  Best for: Vehicles under warranty, Known software issues requiring a manufacturer-specific reflash, Complex network diagnostics requiring specialized data bus tools
  Downsides: Highest labor rates, May default to replacing the entire steering rack rather than performing detailed wiring repairs (Typical cost: +50% vs. baseline)
• Independent Shop: Best fit for most scenarios. A qualified independent shop easily handles power/ground issues at a lower cost. Ensure they are comfortable with CAN bus diagnostics.
  Best for: Out-of-warranty vehicles needing common electrical fault repairs (battery, ground, wiring), Shops with strong electrical and diagnostic reputations
  Downsides: May lack the latest manufacturer software for reprogramming modules, Diagnostic skill for CAN bus issues varies widely (Typical cost: +0% vs. baseline)
• Chain Shop: Avoid for diagnosing U0131. They lack the tools for the complex electrical troubleshooting this code requires.
  Best for: Battery testing and replacement
  Downsides: Not equipped for in-depth network diagnostics or module programming, High potential for misdiagnosis and unnecessary part replacement (Typical cost: -10% vs. baseline)

When to Walk Away From the Repair

If the estimated repair cost for a full steering rack replacement exceeds 50% of the vehicle's private-party market value, seriously consider alternatives to repair.

• Car worth $8000, fix is $2200: Fix it. The repair cost is significant but well below the 50% threshold.
• Car worth $4500, fix is $2500: Walk away. The repair cost exceeds 50% of the car's value.
• Car worth $6000, fix is $2800: Borderline. Get a second opinion to confirm the diagnosis. Explore using a remanufactured part to lower costs.

What Scan Tool You Need for This Code

Minimum: A scanner capable of performing a full system scan ('All Module Scan') to read codes from the BCM, ABS, and PSCM.

A basic $20 code reader only checks the Engine Control Module (ECM). U0131 is a network code stored in multiple modules. A basic reader cannot see the code or identify which modules lost communication.

Budget: BlueDriver Pro (~$120) — Performs a full system scan on all modules, views network topology, and reads specific U-codes stored in each module.

Mid-range: Innova 5610 (~$350) — Offers full system scanning and bidirectional controls to command modules to perform self-tests or re-initialization procedures.

Professional: Autel MaxiCOM MK808 / Launch CRP919XBT (~$450-800) — Professional tools offering bidirectional control, all-module scanning, and advanced module programming required when replacing a steering rack.

Rent vs buy: Auto parts stores offer free 'all module' scans for a one-time diagnosis. If you diagnose regularly, buying a BlueDriver or Innova 5610 is a worthwhile investment.

How to Clear the Code After You Fix It

1. Reconnect battery if disconnected for repair.
2. Use a professional OBD-II scan tool to clear codes from ALL modules.
3. Turn the ignition off, wait 1 minute, then start the vehicle to verify the code does not return.
4. Perform a drive cycle to set all readiness monitors.

Drive cycle (~20 minutes): Cold start (sit overnight) -> 3 min idle -> 15 min mixed city/highway driving at steady speeds around 55 mph with periods of deceleration -> Park and idle for 1 min -> Key off.

Readiness monitors affected: This code does not directly affect emissions monitors., Clearing the code resets ALL readiness monitors to 'Not Ready', causing an automatic emissions test failure.

Before emissions retest: drive at least 50 miles to fully set monitors.

Watch out for:

• Disconnecting the battery does not clear a hard fault; the code returns instantly upon reconnection.
• Basic code readers only clear the ECM and leave the U0131 code stored in the BCM or ABS.
• Driving immediately to an emissions test after clearing codes results in failure due to 'Not Ready' monitors.

Will This Fail Emissions / State Inspection?

Yes — this code typically fails an OBD-II emissions inspection.

• California: An illuminated Check Engine Light is an automatic failure. A drive cycle must be completed to set readiness monitors after repair.
• New York: An active U0131 code with the MIL on results in an immediate OBD-II inspection failure.
• Texas: An illuminated Check Engine Light is an automatic failure in emissions-testing counties. The repair must be made and the light turned off to pass.

Most Commonly Affected Vehicles

• Chevrolet/GMC Silverado/Sierra, Tahoe/Yukon (2014-2020) — Extremely prone to a poor ground at location G218 under the driver's side dash (TSB #PIT5405C) and chafed wiring under door sill plates (TSB #PIT5457D). Some 2015 models faced safety recall #14743B for sudden assist loss.
• Ford F-150 (2011-2014) — Known for failures of the entire electric power steering rack (EPAS), which integrates the PSCM. Connectors on the rack frequently corrode. A 2014 recall (14S09) addressed an incorrectly installed sensor magnet.
• Ford Focus (2012-2018) — Intermittent U0131 codes frequently stem from a weak battery or poor chassis ground connections. Replacing the battery often resolves the issue temporarily, but high-quality Silver-Calcium batteries are required for long-term stability.
• Chrysler/Dodge/Jeep Grand Cherokee, Ram 1500, Charger (2011-Present) — Manufacturing defects like weld spatter or excess glue under ground lugs cause intermittent communication loss. TSBs S1919000004 and S2208000063 instruct technicians to clean specific ground studs (like G908A).
• Honda Civic (2006-2015) — U0131 indicates an F-CAN communication failure between the gauge control module and the EPS unit. Diagnosis requires checking continuity on specific wires between the EPS unit and the ECM.
• Subaru Legacy, Outback, Forester (2018-2022) — Intermittent U0131 codes simultaneously disable the EyeSight driver assist system, which relies on steering input. The cause typically traces to wiring or the PSCM integrated into the steering gearbox.
• Hyundai/Kia Sonata, Optima, Elantra (2011-2015) — Subject to recalls for power steering problems. A 2016 recall for the 2011 Sonata (NHTSA #16V190000) replaced the EPS control unit circuit board due to inadequate protective coating.
• Land Rover Range Rover, Range Rover Sport, Evoque (2012-2016) — TSB SSM71278 states U0131 is primarily a symptom of low battery voltage or high resistance at the EPAS ground points in the front wheel arches (G1D132 & G4D178), not a failed PSCM.

Manufacturer-Specific Notes

• General Motors (GM): GM issued multiple TSBs for U0131. TSB #PIT5405C addresses a poor ground at G218 (dash insulation trapped under the lug), #PIT5457D covers chafed wiring under door sill plates, and #20-NA-113 resolves a software glitch requiring a reprogram.
• Ford: A failing battery or corroded terminals frequently cause intermittent power steering faults. Replacing the PSCM or steering rack requires programming with software like FORScan to restore 'as-built' data.
• Chrysler (FCA/Stellantis): FCA TSBs highlight factory defects, like weld spatter or excess glue on grounding points, causing high resistance. Technicians must inspect and clean these ground studs before replacing modules.
• Land Rover: Electrical systems are highly sensitive to voltage drops. TSB SSM71278 confirms U0131 stems from a weak battery, improper shutdown procedures, or corroded EPAS ground points in the front wheel arches.

Real Owner Stories

2015 GMC Sierra 1500 with intermittent power steering loss

Owner experienced intermittent power steering loss, a 'Service Power Steering' message, and multiple dash warning lights at low speeds.

What they tried:

1. Tested battery and alternator, both passed.

Outcome: The owner located the G218 ground stud behind the driver's side A-pillar trim. Factory sound deadening mat was trapped under the ground terminal. Removing the mat, cleaning the contacts, and retightening the ground permanently resolved all symptoms.

Lesson: On GM trucks, always check the G218 ground point (TSB #PIT5405C) before replacing parts. This factory defect is a zero-cost fix for U0131.

2013 Ford F-150 with complete power steering failure

Power steering failed completely a week after suspension repairs. The dealer quoted $3,000 for a new steering rack.

What they tried:

1. Replaced the entire steering rack assembly with a new part.

Outcome: The new rack worked for one day before failing. The owner wiggled the top connector on the steering rack (part # WPT931) while the engine ran and found the power steering cut in and out. Replacing the faulty electrical connector fixed the issue.

Lesson: Do not assume the most expensive part failed. Wiggling harnesses and connectors helps pinpoint intermittent open circuits.

2020 Jeep Cherokee with U0131 and no power steering

Power steering failed and code U0131 triggered. The owner researched common Jeep electrical issues.

What they tried:

1. Checked standard fuses.
2. Inspected the main fuse block on the positive battery terminal.

Outcome: The owner found the first large fuse (F1) in the battery fuse block was blown. Replacing the fuse block assembly (OEM #68365044AA) restored power steering and cleared the code.

Lesson: On FCA vehicles, high-amperage fuses for the power steering system reside in a special block on the positive battery terminal. Always inspect these first.

How to Prevent This Code From Triggering

• Maintain a Healthy Battery and Connections (Every 6 months) — Low voltage is a top cause of communication codes. Clean battery terminals and load-test the battery annually after it reaches 3 years of age.
• Apply Dielectric Grease to Key Connectors (During related service) — Dielectric grease repels moisture. Applying it to the seals of exposed connectors, like the steering rack harness, prevents corrosion and high resistance.
• Inspect and Clean Chassis Ground Points (Every 2 years in 'Salt Belt' regions) — Corrosion at chassis ground points creates high resistance. Cleaning and protecting major ground straps prevents network failures.
• Use a Battery Tender for Stored Vehicles (As needed) — A battery tender maintains optimal voltage during storage, preventing low-voltage conditions that trigger communication faults on startup.

Frequently Asked Questions

Is it safe to drive my car with a U0131 code?

No, driving is strongly discouraged. The steering becomes extremely heavy and difficult to control, posing a severe safety risk during emergencies or at low speeds. You must service the vehicle immediately.

Can a bad battery cause the U0131 code?

Yes. A weak battery providing unstable voltage is a primary cause of this code across all manufacturers. Always perform a comprehensive battery and charging system load test before replacing expensive modules.

Will clearing the code fix my power steering?

No. Clearing the code only erases the fault from the module's memory. If you do not fix the underlying electrical problem, the code returns instantly and power steering remains disabled.

What is the most common misdiagnosis for U0131?

The most costly misdiagnosis is replacing the power steering rack without testing the electrical system. Technicians frequently discover the actual cause is a weak battery, a corroded ground wire, or a blown high-amperage fuse.

My power steering failed right after hitting a pothole. Could that be the cause?

Yes. A sharp impact severs corroded wires or dislodges loose connections. This code also frequently appears after collision repairs where a ground wire was left disconnected or a harness was pinched.

How much does it cost to fix a U0131 code?

Costs vary dramatically based on the root cause. A simple wiring repair or ground cleaning costs $150-$500, while replacing the entire steering rack assembly ranges from $1,500 to over $4,000 at a dealership.

Do I have to go to the dealer to fix this?

Independent shops easily handle diagnosis and wiring repairs. However, replacing the Power Steering Control Module requires special programming and calibration, demanding manufacturer-specific software typically found at dealerships.

Can I just reset the power steering light?

In rare cases, a temporary voltage drop triggers the code, and restarting the car restores function. However, if the light returns, a persistent hardware or wiring fault exists that requires proper diagnosis.

Key Takeaways

• Code U0131 indicates the Power Steering Control Module (PSCM) is offline, causing an immediate and dangerous loss of power steering assist.
• Test the battery and ground connections first; a weak battery under 12.4 volts or a corroded ground (like GM's G218) causes the majority of these faults.
• Never replace the $1,500+ steering rack without performing a full-module OBD-II scan to rule out blown fuses or CAN bus wiring damage.
• If the steering rack requires replacement, factor in $125 to $250 for professional dealer-level programming to sync the new module with the vehicle.