Kenworth and Peterbilt Heavy Duty Diagnostic Scanners

Written by the YOUCANIC technicians in Towson, Maryland, from the UCAN-HD-A coverage database and our own shop work. Updated October 24, 2026.

A Kenworth or a Peterbilt built in the last decade most likely carries a Paccar MX engine, and the MX is where the money goes when a truck derates: the DPF, the DEF dosing system, the EGR valve, the variable geometry turbo and the injectors all have routines that the dealer runs from a laptop with a subscription. The UCAN-HD-A puts those routines on a tablet with free updates. The Kenworth entry in the coverage database covers the chassis side, codes and live data by model and year from the T2000 era to the T680 Next Gen, and the Paccar entry carries the engine and aftertreatment work for every MX control module generation from 2012 on. Peterbilt trucks share the Paccar engines and the Cummins option, so the same kit covers them through those entries. Pick by what you need to do, then check the connector note.

Which Scanner Do I Need For A Kenworth Or Peterbilt?

CLASS 4 TO 8 TRUCKS, BUSES, ENGINES AND EQUIPMENT

UCAN-HD-A

Full system heavy duty scanner on SAE J1939, J1708 and J1587 with a wireless VCI and the 9 pin, 6 pin and OBD2 connectors in the case. Reads the Kenworth chassis entry and the Paccar MX engine and aftertreatment modules, runs the regeneration, injector, EGR, turbo and DEF routines, and graphs live data. Free updates, no subscription. The tool to own if you keep a Kenworth or Peterbilt working.

PICKUPS, VANS AND CARS

UCAN-II Pro, new or open box

Full system, bidirectional, lifetime free updates, with a built in TPMS module. The scanner for the Ford, RAM, GM and Sprinter pickups and vans that run alongside the tractors. It does not speak J1939 or J1708, so it is not the tool for the Class 8 truck; for a mixed fleet you want both.

What The UCAN-HD-A Does On A Kenworth Or Peterbilt

• ✓ Kenworth chassis entry: ECU Information, Read Codes, Erase Codes and Live Data by model and year, from the T2000, T600, T800 and W900 entries of the 1990s to the T680 Next Gen, T480 and T880 entries of 2021
• ✓ Paccar MX engine and aftertreatment modules for the PMCI, PMCI2, PCI, PCI UDS, EAS-2, EAS-3 and EAS-4 control module generations, 2012 to 2023, with ECU information, codes, live data, Active test and Special functions
• ✓ Regenerate the DPF and DPF Service Regen, Reset the soot level, Install a new DPF, Install a cleaned DPF, Enable regeneration after aftertreatment system repair, Check the particulate matter sensor
• ✓ Cut-out the injectors, Check the cylinder compression, Compression test, Automated cylinder performance test, Injector codes and Change the injector codes, Pump unit codes and Change the pump unit codes
• ✓ DEF and SCR: AdBlue circuit test, AdBlue filter leakage test, Dosing module test, Tank valve heater, the DEF pipe, pump and tank heater activations and tests, Activate the DEF reverting valve, Check the DEF pump module pressure and DEF output, Prime the system with the DEF pump
• ✓ Derate recovery after the repair: Disable Exhaust Gas Recirculation (EGR) derate, Disable the EGR derate, Disable Diesel Exhaust Fluid (DEF) derate, Disable the DEF derate, Disable Diesel Exhaust Fluid (DEF) torque limitation
• ✓ Air side: Initialize the Exhaust Gas Recirculation (EGR), Initialize the BPV, Activate the BPV actuator, Install and calibrate the VTG turbocharger actuator, Diagnose the turbo actuator, Evaluate the turbo actuator functionality, Turbo Actuator Effort Test, Boost pressure control valve, Activate the air shutoff valve, Fan test
• ✓ Engine brake and governor: Engine brake MX, Activate the MX Engine Brake, Assess the MX engine brake, Exhaust brake, Speed limiting, Enable or disable the engine idle shutdown timer
• ✓ Records and lamps: Engine data logger, Clear the snapshot recorder, Clear the fast stop recorder, Read CAL-ID and CVN, Activate the red engine warning, Activate the yellow engine warning, Activate the malfunction indicator lamp
• ✓ Cummins powered Kenworth and Peterbilt trucks use the Cummins entry for the engine side, with Cylinder Cutout Test, Aftertreatment Diesel Particulate Filter Regeneration and the DEF doser tests

Service Functions By Job On A Kenworth Or Peterbilt

On the tablet you pick the make entry, then the model or engine control module generation, then the module, the function category and the routine. Kenworth holds the chassis entry; the Paccar entry holds the Engine control module and Aftertreatment modules with their Active test and Special functions lists. These are the routines the coverage database lists, grouped by the job you are doing. Names are as they appear on the tablet. Coverage varies by model year, engine and software, so check yours before you order.

What The Scanner Sees On A Kenworth Or Peterbilt

Three entries pulled from the coverage database. The Kenworth entry lists codes and live data by model and year; the Paccar entry lists the engine and aftertreatment modules with the routines on top of that.

Symptom, Then The Routine That Fixes It

• DPF lamp, high soot or a derate on a Paccar MX: Regenerate the DPF or DPF Service Regen in the Paccar entry, then Disable the EGR derate or Disable the DEF derate once the repair is done.
• A new or cleaned DPF just fitted: Install a new DPF or Install a cleaned DPF, then Reset the soot level and Enable regeneration after aftertreatment system repair.
• DEF quality or dosing codes: AdBlue circuit test, Dosing module test, the DEF heater tests and Check the DEF pump module pressure and DEF output.
• A weak or dead cylinder: Cut-out the injectors and Automated cylinder performance test, then Compression test.
• New injectors or a new fuel pump: Change the injector codes or Change the pump unit codes.
• Boost or turbo actuator codes: Diagnose the turbo actuator, Turbo Actuator Effort Test and, after a replacement, Install and calibrate the VTG turbocharger actuator.

Frequently Asked Questions

Will it run a forced regen on my T680 with a Paccar MX engine?

Yes. Regenerate the DPF and DPF Service Regen are in the Paccar entry under the Engine control module and Aftertreatment modules, alongside Reset the soot level and the Install a new or cleaned DPF routines. Confirm your engine control module generation in the coverage checker first.

Is Peterbilt covered?

Through the engine. Peterbilt is not a separate entry in the database, but a Peterbilt with a Paccar MX uses the same Paccar engine and aftertreatment entry as a Kenworth, and a Cummins powered Peterbilt uses the Cummins entry. Send the VIN to support@youcanic.com before you order and we will confirm the chassis side too.

Can it clear a DEF or EGR derate after the repair?

The Paccar entry lists Disable the DEF derate, Disable Diesel Exhaust Fluid (DEF) torque limitation, Disable the EGR derate and Disable Exhaust Gas Recirculation (EGR) derate as service routines for use after the fault is repaired, plus Enable regeneration after aftertreatment system repair.

Which connector does my truck have?

The Paccar entries list the 9 pin Deutsch Type I general connector, the 9 pin Deutsch Type II green connector and the SAE J1962 OBDII connector, and the UCAN-HD-A kit includes all three plus the 6 pin Deutsch for the older J1708 trucks.

Can it change the road speed limiter or flash the ECM?

It does not flash an ECM. The Paccar entry lists Speed limiting and Enable or disable the engine idle shutdown timer as routines on supported engines; dealer password protected parameters stay with the engine maker's software.

How do I know my exact truck and function are covered?

Use the coverage checker by make, model and engine, or call 1-888-959-4265, Monday to Friday 9 AM to 4 PM Eastern, with the VIN and the engine, and a technician will tell you plainly. If it does not do what you need, we will say so. Every scanner also comes with 31 day returns, no questions asked.

Cummins powered? See the Cummins engine page. For other makes see the scanners by make hub, the service functions explained one job at a time, and the step by step repair guides on youcanic.com.