By iCarsoft Official Store Technical Team, Automotive Diagnostics Editors · Updated October 14, 2026 · Technical sources checked
Quick Answer
U0131 can map to PSCM or, on some GM vehicles, be a mis-mapped U0126 steering-angle fault. Check RPO NV8 and bus identity before authorizing a steering module.
What Does the U0131 Code Mean?
GM PIT5755 records U0131 as a loss of communication with K43 Power Steering Control Module on vehicles with RPO NV8, but warns that some vehicles without NV8 may have an incorrect EBCM mapping of U0126 steering-wheel-angle communication as U0131. The full fault record determines the test branch.
GM PIT5755 records U0131 as PSCM communication loss on 2020 Silverado/Sierra 2500/3500 when RPO NV8 is present, but warns that non-NV8 vehicles may have an EBCM mapping U0126 steering-angle loss as U0131. The code therefore requires RPO and bus identification before parts decisions. The RPO condition is not a minor detail.
An EBCM code from an NV8-equipped truck points the investigation toward the K43 communication path, while a non-NV8 mapping may require the B99 steering-angle branch. A generic parts search using only U0131 can therefore select the wrong controller. Preserve RPO data, companion U0126/U-codes and the actual module response. The bulletin’s mapping example does not establish a universal steering-assist test, pinout or programming outcome; those remain VIN-specific.
Do not use a front power-steering interpretation simply because a steering complaint is present. GM’s RPO-dependent note shows that the same displayed code can be a mapping problem. The reporting EBCM, current module access and RPO record should be saved as evidence in the article’s diagnostic branch.
The absence of a PSCM response is still not a proof of an internal PSCM defect until supply, ground, bus and configuration checks support that conclusion. Likewise, a B99 steering-angle path requires its own confirmation.
GM PIT5755 records U0131 as a loss of communication with K43 Power Steering Control Module on vehicles with RPO NV8, but warns that some vehicles without NV8 may have an incorrect EBCM mapping of U0126 steering-wheel-angle communication as U0131.
GM PIT5755 — U0131 PSCM/B99 mapping and bus diagnostic context identifies U0131 as Lost Communication with Power Steering Control Module in a bounded vehicle or module context. The source supplies terminology and limited mechanism evidence; it does not provide a universal topology, threshold or replacement instruction. GM PIT5755 records U0131 as a loss of communication with K43 Power Steering Control Module on vehicles with RPO NV8, but warns that some vehicles without NV8 may have an incorrect EBCM mapping of U0126 steering-wheel-angle communication as U0131.
2020 Chevrolet Silverado/GMC Sierra 2500/3500 diagnostic tip; RPO and module mapping are decisive. Do not road-test a vehicle with abnormal steering assist or stability warnings merely because the code clears.
Save the full module wording and suffix before clearing; they can change the test path.
Separate U0131 from adjacent fault families
| Code | General description | Key distinction |
|---|---|---|
| U0131 | Lost Communication with Power Steering Control Module | The named message endpoint differs from the bus-off and body-module records below. |
| U0073 | Control Module Communication Bus A Off | A bus-off result is a different network condition; confirm the actual fault record. |
| U0140 | Lost Communication with Body Control Module | A body-network code is not interchangeable with this module-specific result. |
Record the complete U0131 description. The suffix, reporting module and companion faults can change the diagnostic path. Use the manufacturer's full wording and test procedure for the exact vehicle.
U0131 Symptoms and Likely Causes
Record U0131 symptoms and fault status; symptoms alone cannot identify a failed part.
Review companion faults.
Record the exact warning, when it appeared and which function changed; it is evidence, not proof of a failed controller.
Compare saved multi-module reports with supported live data; unavailable data does not identify the cause.
Preserve service history and inspect the disturbed branch first while treating timing as a clue.
Save every module's codes and status; a shared supply or network code can change the diagnostic order.
Practical cause-checking order
- GM RPO/module mapping does not match the presumed PSCM path: Use the power-steering control module power, ground, wake and CAN path diagram to identify the required feed, ground and wake state. A missing response is a starting observation; the approved supply checks must determine whether the controller could operate in that state.
- K43 PSCM power, ground or communication branch fault: Inspect the connector and communication branch identified for this VIN, especially any area disturbed during recent work. Document the failed terminal or wiring test instead of attributing every network record to one visible connector.
- B99 steering-angle mapping or EBCM interpretation condition: Compare the fitted equipment, gateway route and current configuration with manufacturer information. A generic code label cannot show whether a route or software change is appropriate; use an applicable OEM instruction before changing either.
- Gateway, software or wake state affecting the mapped endpoint: Compare the reporting receiver with direct access to the named controller. Record whether the condition is current, intermittent or stored, and repeat only the prescribed wake or verification sequence; do not use repeated battery resets as diagnosis.
- Internal controller fault only after the RPO-specific branch passes: Consider the named controller only after the applicable external checks support that conclusion. Save the evidence that excludes supply, connector, communication and configuration branches, and include required setup and functional verification in the proposed repair.
Did U0131 appear after recent steering-column, battery, module or harness work? Recheck the documented connections, parts and setup steps affected by that work. Record battery and software history; a post-repair code does not prove the new part is defective.
How Serious Is U0131, and Can You Drive?
Do not road-test a vehicle with abnormal steering assist or stability warnings merely because the code clears. Follow the owner manual and all vehicle warnings. U0131 does not establish a safe remaining driving distance. Stop safely and arrange qualified inspection or towing for abnormal function; do not use a successful scan as permission to bypass a warning.
Record warning messages, operating conditions and service history. Do not induce wheel slip, emergency braking or a handling event on public roads. A red stop warning or abnormal control overrides any verification plan.
Stop and arrange a tow if steering, braking, propulsion, charging, parking-brake or other safety behavior is abnormal.
Follow the vehicle-specific electrical, steering, suspension or driveline safety precautions. Do not bypass interlocks or command powered safety components outside the approved procedure.
How to Diagnose U0131 in the Right Order
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Identify the application and preserve evidence
Save the EBCM record, steering/stability warnings and all companion U-codes.
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Inspect the relevant physical and electrical path
Check RPO NV8 and identify whether the vehicle has K43 PSCM; on non-NV8 vehicles investigate the B99 steering-angle mapping first.
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Confirm architecture and prerequisites
Use the GM Data Bus Diagnostic Tool or VIN-specific diagram to separate PSCM communication from B99 communication.
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Separate network behavior from system behavior
Inspect the applicable feeds, grounds and both bus branches without assuming one connector or pinout across trims.
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Prove the repair path before parts
Complete the steering/stability diagnostic for the actual mapped module and do not replace PSCM on the code alone.
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Verify the original condition after repair
Verify steering assist, stability readiness and warning state through the prescribed GM functional check.
Specifications are vehicle-specific. Use the exact VIN specifications, approved test points and required operating state. No generic value or drive cycle can replace the applicable procedure. Manufacturer examples here do not establish specifications for other applications.
U0131 Repairs and Cost Planning
A U0131 repair must address the demonstrated failure. Do not replace an assembly from the code alone.
Recheck installation and required setup after repair. 2020 Chevrolet Silverado/GMC Sierra 2500/3500 diagnostic tip; RPO and module mapping are decisive.
Ask the shop to name the failed branch and the measurement supporting each proposed repair.
Authorize diagnosis before parts while the cause remains uncertain.
| Possible path | Quote basis |
|---|---|
| Repair the demonstrated power, ground, connector, harness, gateway or network branch | VIN-specific quote |
| Restore configuration, software or required setup only through the VIN-specific procedure | VIN-specific quote |
| Replace the isolated controller or assembly only after external evidence and the OEM test support that path | VIN-specific quote |
These are alternative repair paths, not prices to add together. Request a VIN-specific quote separating diagnosis, parts, labor, fluids, taxes, required setup and verification. Ask which failed test supports the proposed repair and whether warranty coverage applies.
Using iCarsoft CR Pro S for U0131
On a supported vehicle, iCarsoft CR Pro S can save accessible faults, available freeze frame, live data and diagnostic reports. Preserve the U0131 evidence before clearing.
Compare the saved and final module records. Scan data supports diagnosis but does not replace the OEM reference, physical measurement or safety-system functional check.
Preserve the power-steering control module power, ground, wake and CAN path evidence
iCarsoft CR Pro S
Review supported codes and relevant live data together. Confirm the exact VIN, controller access, PIDs and any requested active test with iCarsoft before purchase; generic product capabilities do not guarantee a U0131-specific function.
Check current CR Pro S price and availabilityCheck CR Pro S compatibility by VINThe official product page describes supported full-system diagnostics, available live data, freeze frame and diagnostic reports; exact controller coverage and active tests depend on the VIN and software. Confirm the requested function by VIN before purchase. Follow OEM prerequisites and stop for abnormal operation.
Know the measurement boundary. Scan data describes ECU-provided information; it does not directly prove the physical condition of the power-steering control module power, ground, wake and CAN path. Where required, use approved multi-module scan access, wiring diagram, voltage-drop/continuity tools and the VIN-specific network procedure and compare reported values with the relevant measured evidence.
Verify the U0131 Repair
After repair, verify installation, clearance and required setup. Save the final findings and clear only erasable records as instructed. Battery disconnection is not a repair.
Run the manufacturer's applicable verification conditions in a safe workshop or route. Compare the original operating state with current data for the power-steering control module power, ground, wake and CAN path, and check current and pending faults in related modules. A clean start or idle period does not prove the repair; use the OEM functional check for the affected system.
Compare the original and final fault status. Record the functional-check result and whether the original event returned.
If U0131 returns, compare its suffix, status, failure order and operating conditions with the saved baseline before replacing another part. Revisit the failed branch and inspect anything disturbed. Confirm the prescribed affected-system functional verification separately from code clearing.
Verification follows the system involved. After saving the original evidence, use the OEM procedure to clear erasable records, complete any required calibration or functional check, and compare the final module status with the original warning and fault conditions.
Related Power-Steering Control Module Power, Ground, Wake And CAN Path Code Guides
Compare the related monitor families below. Shared symptoms or components do not make their repair procedures interchangeable.
U0131 Frequently Asked Questions
Does U0131 prove the Power Steering Control Module is bad?
No. GM PIT5755 records U0131 as a loss of communication with K43 Power Steering Control Module on vehicles with RPO NV8, but warns that some vehicles without NV8 may have an incorrect EBCM mapping of U0126 steering-wheel-angle communication as U0131. Use the VIN-specific procedure to prove the responsible feed, connector, network branch or controller before replacing parts.
What should I check first for U0131?
Save every module's codes and freeze frame before clearing. Confirm the full definition, suffix and VIN architecture. Then inspect recent steering-column, battery, module or harness work, connectors and shared supplies. Those facts determine whether the next test needs approved multi-module scan access, wiring diagram, voltage-drop/continuity tools and the VIN-specific network procedure or a manufacturer-specific functional procedure.
Can I drive with the U0131 code?
Do not road-test a vehicle with abnormal steering assist or stability warnings merely because the code clears. Follow the owner manual and all vehicle warnings. U0131 does not establish a safe remaining driving distance. Stop safely and arrange qualified inspection or towing for abnormal function; do not use a successful scan as permission to bypass a warning.
Why did U0131 return after a part was replaced?
Compare the new record with the original suffix, reporting module and operating state. A replacement may leave an external message-path fault, installation issue or required setup unresolved. Reopen the failed diagnostic branch instead of treating the returning code as proof that the new part is defective.
What should a U0131 repair estimate include?
Ask for the failed-test evidence and a VIN-specific breakdown of diagnosis, parts, labor, taxes, required setup and verification. A code alone cannot establish the repair price.
Can CR Pro S diagnose and clear U0131?
On a supported vehicle, CR Pro S can organize available faults, freeze frame, live data and reports, and can clear erasable records after repair. Confirm exact ECU coverage. It cannot replace the OEM functional procedure or physical measurements for the power-steering control module power, ground, wake and CAN path.
The iCarsoft Official Store Technical Team maintains the store's fault-code library. This guide organizes published technical references and verified product information; it does not document a hands-on test of a particular vehicle or claim an individual engineer's review.
Technical and cost references
- GM PIT5755 — U0131 PSCM/B99 mapping and bus diagnostic context. Primary-source terminology and bounded mechanism evidence; not a universal repair criterion.
- Subaru Electrical Systems Operation & Diagnosis Module 602. OEM training context for no-message communication faults; it does not set another vehicle’s topology or thresholds.
Product information: Official iCarsoft CR Pro S page.
Editorial note: General diagnostic education, not a substitute for the owner's manual, current VIN-specific service information or professional inspection. Test limits, procedures, coverage and costs vary. Related articles provide context; apply only the specifications and repair procedures that match the vehicle. No universal failure rate, repair price or outcome is implied.
