By iCarsoft Official Store Technical Team, Automotive Diagnostics Editors · Updated October 14, 2026 · Technical sources checked
Quick Answer
U0134 records lost communication with power steering control module rear. It does not prove a failed module; preserve the full scan and use the VIN-specific network procedure before selecting a repair.
What Does the U0134 Code Mean?
The Autel official DTC table lists U0134 as Lost Communication with Power Steering Control Module Rear. That terminology identifies the named message endpoint; it does not establish a vehicle-specific topology, threshold or failed part. The full fault record determines the test branch.
The Autel table lists the rear power-steering controller as the named message endpoint. It does not say which vehicle uses rear steering or where that controller sits. Separate a rear-steering communication record from front power-steering, steering-angle and chassis warnings by reading the VIN-specific module list and reporting module. The likely diagnostic branches are the controller’s approved supply, ground, wake, connector, network route, configuration or internal availability.
Do not infer rear-steer hardware failure from the code or use a front-steering pinout. If rear steering or stability behavior is abnormal, safety takes precedence over a drive test. Capture the full scan and status before clearing because companion bus faults can change the order of testing. Rear-steering equipment is not universal, so the presence of U0134 itself should prompt an equipment and configuration check.
A receiver can name a rear power-steering controller when the network path is interrupted, but the repair branch depends on whether the vehicle actually carries that system and how its gateway is configured. Preserve the scan status and any stability or steering warning before clearing. If the module is reachable, compare the stored event with current behavior; if not, prove external availability under the approved procedure.
The Autel table gives no universal actuator position, steering-angle or bus measurement. The rear designation can also reflect a manufacturer naming convention rather than a universal physical location. Use the service diagram to identify the module, connector and gateway route. If the module responds, compare its stored status with the receiver’s U0134 record and check whether the event is intermittent.
If it does not respond, the diagnostic order should follow the approved external checks before any replacement. Keep front steering, rear steering and steering-angle messages distinct in the final report so that a shared warning does not become a false parts diagnosis. Do not use a generic front-steering scan result to validate the rear controller path.
If several steering-related codes appear together, use the module map to identify the common route before inspecting a local controller. A rear-steering warning remains a separate functional finding. Document whether the module is current, historical or intermittent, and keep any steering-angle or front-assist code as a separate branch. The code table does not supply a safe road-test method.
The word “Rear” is an architecture clue, not proof that the vehicle is equipped with rear steering; confirm configuration first.
Autel AL519 PDF p.99 lists U0134 as Lost Communication with Power Steering Control Module Rear. The code table confirms the endpoint wording only and supplies no vehicle-specific rear-steering procedure.
Verify the vehicle actually has a rear power-steering system and identify the reporting receiver. Inspect the VIN-correct branch and perform steering/stability checks; do not authorize a rear actuator or controller solely from the code.
Save the full module wording and suffix before clearing; they can change the test path.
Separate U0134 from adjacent fault families
| Code | General description | Key distinction |
|---|---|---|
| U0134 | Lost Communication with Power Steering Control Module Rear | 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 U0134 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.
U0134 Symptoms and Likely Causes
Record U0134 symptoms and fault status; symptoms alone cannot identify a failed part.
Check whether companion faults share a proven cause.
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
- Rear power-steering controller supply or wake unavailable: Use the rear power-steering control module 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.
- Rear-steering connector or network 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.
- Vehicle configuration or gateway route differs from the presumed rear system: 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.
- Controller absent or not responding in a vehicle without confirmed rear steering: 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 steering checks: 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 U0134 appear after recent battery, interior, module, harness or software 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 U0134, and Can You Drive?
The code alone cannot establish a safe driving distance. Follow the owner manual and vehicle warnings; stop safely and arrange qualified diagnosis if the affected function is abnormal.
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 a safety-related function or the affected system behaves abnormally.
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 U0134 in the Right Order
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Identify the reporting and named modules
Save the scan, reporting module, U0134 status, steering warnings and configuration information.
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Preserve the application and status evidence
Confirm rear-steering equipment and the VIN-specific controller identity and bus route.
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Inspect only the proven network branch
Check only approved supply, ground, connector and network conditions for that controller.
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Separate communication from system performance
Separate communication availability from actual rear-steering and stability performance.
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Choose repair only after external evidence
Use the OEM procedure to distinguish configuration, gateway, wiring and controller causes.
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Verify the affected function and network state
Complete the prescribed steering and stability verification before returning the vehicle.
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.
U0134 Repairs and Cost Planning
A U0134 repair must address the demonstrated failure. Do not replace an assembly from the code alone.
Recheck installation and required setup after repair. U0134 is not interchangeable with U0131 front power steering or U0126 steering-angle communication.
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 U0134
On a supported vehicle, iCarsoft CR Pro S can save accessible faults, available freeze frame, live data and diagnostic reports. Preserve the U0134 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 rear power-steering control module 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 U0134-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 rear power-steering control module. 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 U0134 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 rear power-steering control module, 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 U0134 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 Rear Power-Steering Control Module Code Guides
Compare the related monitor families below. Shared symptoms or components do not make their repair procedures interchangeable.
U0134 Frequently Asked Questions
Does U0134 prove the named module is bad?
No. The Autel table provides the code label only. Prove the VIN-specific supply, ground, connector, network and controller evidence before replacing a part; a clear scan does not prove the affected system is ready.
What should I check first for U0134?
Save every module's codes and freeze frame before clearing. Confirm the full definition, suffix and VIN architecture. Then inspect recent battery, interior, module, harness or software 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 U0134 code?
The code alone cannot establish a safe driving distance. Follow the owner manual and vehicle warnings; stop safely and arrange qualified diagnosis if the affected function is abnormal.
Why did U0134 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 U0134 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 U0134?
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 rear power-steering control module.
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
- Autel AL519 Diagnostic Trouble Code Definitions. Official code terminology, PDF p.99, exact U0134 entry; no vehicle-specific repair procedure.
- GM PIT5755 — module and bus mapping example. Manufacturer network context illustrating why module identity and application scope must be confirmed; not a universal U0134 procedure.
- Subaru Electrical Systems Operation & Diagnosis Module 602. General CAN no-message and safety context; not a U0134 wiring or threshold source.
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.
