Modern trucks do not fail with a simple knock and a puff of smoke. They fail with a dash full of lamps, a derate at 40 kilometres an hour, and a parked regen that will not complete on the shoulder of the 401. KG Truck Services has performed 29,000+ electronic diagnostic tests in Mississauga, and that volume is the point: we see the same Cummins, Detroit, PACCAR, Volvo, and Mack control systems every week, so a code is a starting point, not a parts order.
ECM, PCM, and aftertreatment diagnostics
We connect to the engine control module, body controllers, ABS, and aftertreatment with OEM-level software — not a generic code reader that lists every pending fault and calls it a diagnosis. That means we can read live data, freeze-frame, injector contribution, NOx sensor correlation, DPF soot and ash load, DEF quality, and turbo actuator position. We program and calibrate ECMs and PCMs when a module is replaced, when parameters need to match a rebuilt engine, or when a used truck arrives with the wrong calibration for the chassis it is sitting in.
Aftertreatment is where most trucks lose days. A DPF that will not regen, a DEF doser that is crystallized, an EGR valve that is carboned shut, or a NOx sensor that is lying to the ECM will all look like “emissions problems.” They are not the same repair. We separate sensor failure from actual restriction, and we separate a wiring issue from a failed module. If the filter is overloaded, we tell you whether a forced regen, a clean, or a replacement is the honest fix. If the truck is derated because someone deleted or tampered with the system, we tell you that too — and what it will take to make it legal for Ontario roads and a DriveON emissions test.
Electrical, ABS, and hard-to-find faults
Not every problem is in the ECM. Corroded connectors at the firewall, chafed harnesses along the frame rail, failing batteries that brown-out modules, and poor grounds will throw codes that send people to the dealer for a $4,000 module that was never bad. We load-test charging systems, voltage-drop grounds, and smoke or scope circuits when a wiring diagram is the only way through. ABS and collision-avoidance systems get the same treatment: wheel-speed sensors, tone rings, and valve blocks diagnosed before anyone replaces a modulator “just in case.”
We also handle the electronics that sit around an engine rebuild: injector coding, turbo actuator setup, idle and derate parameters, and post-repair verification so a mechanically rebuilt motor is not limited by a leftover fault. If you are combining diagnostics with a DriveON emissions test, we can scan, repair, and retest in the same facility instead of towing between a programmer and an inspection lane.
All makes, one shop in the GTA
Freightliner Cascadias, Peterbilt 579s, Kenworth T680s, Volvo VNLs, Mack Anthems, Internationals, and Western Stars all roll into 6771 Columbus Road. The software stack is different; the method is not. Confirm the complaint, pull the complete code set, look at live data under the condition that sets the fault, then repair the cause. Owner-operators get a plain-language explanation. Fleet managers get a work order they can put in the file.
If the truck will not move, ask about mobile diagnostics. If it will roll, book a bay. Either way, call (905) 564-0880 and skip the cycle of replacing sensors until the lamp goes out. That cycle is how diagnostic invoices get bigger than the original failure.
