How to Spot Problems in Your Truck’s Electrical System
When it comes to modern heavy-duty trucks, electrical systems are just as critical as mechanical components. From engine control modules to lighting, GPS, and emissions systems, everything relies on proper electrical function. If you're experiencing strange behavior from your truck, the issue could be electrical—and early detection is key to avoiding costly downtime.
At 6NZ Truck & Equipment Repair Ltd, we offer expert electrical diagnostics and repair services for heavy-duty trucks and industrial equipment throughout Langley, Surrey, Abbotsford, Vancouver, and beyond.
common signs of electrical issues in your truck—and what they might mean.
- Flickering or Dim Lights
- Trouble Starting the Truck
- Dashboard Warning Lights
- Blown Fuses or Relay Failures
- Non-Functional Accessories or Electronics
1. Flickering or Dim Lights
If your headlights, brake lights, or interior lights flicker or appear dim, this could point to:
• A failing alternator
• Loose or corroded wiring
• Weak battery Driving at night or in poor visibility with flickering lights is dangerous and should be inspected right away.
• Loose or corroded wiring
• Weak battery Driving at night or in poor visibility with flickering lights is dangerous and should be inspected right away.
2. Trouble Starting the Truck
Intermittent or delayed starting may be caused by:
• A weak battery
• Faulty starter motor
• Malfunctioning ignition switch
• Corroded battery terminals If your truck takes multiple attempts to start or cranks slowly, it's time to schedule an electrical diagnostic.
• Faulty starter motor
• Malfunctioning ignition switch
• Corroded battery terminals If your truck takes multiple attempts to start or cranks slowly, it's time to schedule an electrical diagnostic.
3. Dashboard Warning Lights
Your truck’s ECU monitors dozens of electrical components. Warning lights like Check Engine, ABS, or Battery Light are your first clue that something is wrong. Ignoring them could lead to bigger issues down the road.
At 6NZ, we use advanced diagnostic scanners to accurately read trouble codes and isolate the issue quickly.
4. Blown Fuses or Relay Failures
Do you frequently replace fuses or relays? This could indicate a deeper issue such as:
• A short circuit
• Overloaded wiring
• Faulty sensors or switches Frequent electrical overloads are dangerous and can result in equipment failure or even fire if left unaddressed.
• Overloaded wiring
• Faulty sensors or switches Frequent electrical overloads are dangerous and can result in equipment failure or even fire if left unaddressed.
5. Non-Functional Accessories or Electronics
Is your GPS, radio, power mirrors, or climate control system acting up? These systems rely on precise electrical connections. When they fail, it often means:
• Faulty modules
• Damaged wiring harnesses
• Grounding issues We can trace the source and restore full functionality to keep your cab comfortable and safe.
• Damaged wiring harnesses
• Grounding issues We can trace the source and restore full functionality to keep your cab comfortable and safe.
common signs of electrical issues in your truck—and what they might mean.
- ECM/ECU diagnostics and repair
- Battery testing and replacement
- Alternator and starter motor service
- Wiring harness inspections and repairs
- ABS, lighting, and sensor system diagnostics
- PTO, relay, and solenoid troubleshooting
- Mobile electrical repair service available
Our experienced technicians specialize in heavy-duty electrical systems, working with top truck brands like Freightliner, International, Kenworth, Peterbilt, Volvo, and Western Star. We also handle electrical repairs for engines from Cummins, CAT, Detroit Diesel, and PACCAR.
