Description

Eaton Fuller TCU Repair Services – Reliable Solutions for Truck Transmission Control Units

At Autolectronix, we specialise in professional Eaton Fuller TCU (Transmission Control Unit) repair services for the trucking industry. The Eaton Fuller range of automated and manual transmissions is widely used in heavy-duty trucks such as Freightliner, International, Kenworth, Peterbilt, Volvo, and Mack. Over time, the TCU (also known as ECM or ECU) can develop electronic faults that leave trucks stranded or operating in limp mode. Replacing a TCU is extremely costly, but our repair service offers a cost-effective and reliable alternative.

Common Eaton Fuller TCU Faults

Truck operators and workshops often face the following problems with Eaton Fuller TCU units:

• Water ingress and corrosion inside the module leading to poor communication or complete failure.

• No communication (no COMs) between the TCU and diagnostic tools, often caused by damaged CAN bus circuits.

• Shift solenoid driver failures, resulting in gear selection issues or trucks stuck in neutral.

• Power supply faults, where the unit receives power but fails to boot up.

• Intermittent operation, where the truck may operate normally one moment and fail the next.

• Fault codes such as actuator errors, gear selection mismatch, or input/output sensor failures.

These issues are common across Eaton AutoShift, UltraShift, and Fuller TCU models.

Why Choose Autolectronix?

Our repair process is designed to deliver fast turnaround times, high-quality workmanship, and long-lasting results:

1. Comprehensive Testing – Each TCU is tested on our in-house electronic benches to simulate real-world truck conditions.

2. Component-Level Repairs – We replace failed transistors, drivers, capacitors, and corroded tracks instead of only swapping boards.

3. Data Integrity Checks – We ensure your unit retains correct programming and calibration for your truck model.

4. Water-Damage Restoration – Units affected by moisture or oil ingress are cleaned, repaired, and sealed against future damage.

5. Warranty Backed – All repairs carry our standard Autolectronix warranty, giving you peace of mind.

Supported Trucks & Models

Our services cover a wide range of Eaton Fuller TCU applications, including:

• Freightliner Cascadia / Columbia with Eaton AutoShift.

• Kenworth T680 / T880 with Eaton UltraShift.

• Peterbilt 579 / 389 automated transmission systems.

• International ProStar / Lonestar with Eaton TCU integration.

• Volvo VNL models fitted with Eaton gearboxes.

• Mack Pinnacle / Granite series with Fuller transmission controls.

If your truck uses an Eaton AutoShift, UltraShift, or Fuller TCU, we can assist with repair services.

The Cost-Effective Alternative to Replacement

Brand-new Eaton Fuller TCUs can cost thousands of dollars and may not always be available locally. By choosing Autolectronix repair services, you benefit from:

• Reduced downtime – fast testing and repairs mean your truck is back on the road quickly.

• Lower costs – repairs are significantly cheaper than new replacement modules.

• Extended lifespan – repaired units often last just as long as replacements when properly sealed and installed.

Typical Part Numbers We Repair

Some common Eaton Fuller TCU part numbers we handle include:

• 4309334

• 4309498

• 4309335

• 4309500

• 4309342

(If your part number is not listed, contact us as we can usually still assist.)

Conclusion

When your Eaton Fuller TCU fails, you don’t need to replace it outright. Autolectronix offers expert repairs, restoring your unit to full working condition. Whether you’re dealing with water ingress, no communication, solenoid driver issues, or intermittent failures, our team has the tools and experience to get your truck back in service.

📩 For professional Eaton Fuller TCU repair services, contact us today at sales@autolectronix.co.za.