2020 Chevrolet Silverado-2500hd Check Engine Light

A steady light signals a stored fault; a flashing light indicates a severe misfire that can quickly damage the catalytic converter.

Your truck’s OBD-II system sets a code to identify the affected system and stores freeze-frame data when the light came on. Common triggers range from a loose gas cap to ignition or fuel issues, especially after towing or big temperature swings along the Wasatch Front. Our team in Murray confirms the code and performs pinpoint testing to find the actual cause before any repair.

• Steady vs. flashing behavior helps gauge urgency
• Code examples: P0442 (EVAP small leak), P0300 (random misfire)
• Schedule an inspection to prevent further damage

The five most common causes are O2 sensor faults, EVAP system leaks, MAF sensor issues, catalytic converter efficiency codes, and ignition misfires.

These issues can appear after fuel stops, filter changes, or heavy towing. Our diagnostic process confirms the code, inspects related components, and tests to the root cause rather than replacing parts on guesswork. Addressing these items early protects fuel economy, drivability, and emissions readiness for inspections in Utah.

• Examples: P0131/P0151 (O2 sensor), P0442 (EVAP small leak)
• P0101 (MAF performance), P0420 (catalyst efficiency)
• P0300 (misfire) can overheat and damage the catalytic converter

If the light is steady, drive cautiously to service; if it’s flashing, stop driving to avoid catalytic-converter damage.

A steady light often reflects a non-urgent fault, but continued driving can worsen fuel economy and emissions. A flashing light means a severe misfire that can overheat the catalyst quickly. In either case, limit load, avoid towing, and plan a prompt diagnosis at Larry H. Miller Chevrolet Murray for a clear repair plan.

• Reduce speed and avoid hard acceleration if the light is steady
• Safely pull over and arrange service if the light is flashing
• Book your visit for a confirmed diagnosis

A parts store reads the code, while our dealer team diagnoses the root cause using GM factory scan tools, technical service bulletins, and OEM procedures.

Codes point to systems, not specific failed parts; multiple causes can trigger the same code. Our OEM-certified technicians access proprietary data, verify sensor signals, and perform isolation testing like smoke checks for EVAP leaks. You receive documented results and a written estimate before any repair.

• Factory scan tool access and guided diagnostics
• Isolation tests (e.g., smoke test, voltage and pressure checks)
• Clear estimate and repair options after testing

No—clearing codes usually sets OBD-II monitors to Not Ready, which can cause an emissions test failure in Utah until drive cycles complete.

After a reset, the truck must complete specific drive conditions so readiness monitors can run and report. If the original fault remains, the light will return and the test may fail again. A proper diagnosis in Murray confirms the cause, restores readiness, and avoids repeat inspections.

• Don’t clear codes right before an inspection
• Complete drive cycles after verified repairs
• Schedule diagnostics to restore readiness

You’ll receive an ETA after our quick initial code scan and triage, once we review fault data on your truck.

Timing depends on what the code reveals and whether isolation tests (like smoke testing for EVAP or scope checks for misfire) are required. Your advisor will outline next steps right after the scan and keep you updated if additional testing is needed. Use our online scheduler to choose a drop-off or wait appointment.

• Immediate OBD-II scan and freeze-frame review
• Pinpoint testing as needed based on results
• Written estimate before any repair begins

LHM Chevy Murray serves drivers from Salt Lake City, South Jordan, West Jordan, Midvale, and Sandy with GM-grade engine light diagnostics. A basic code reader only tells you what system flagged; our factory scan tools pull deeper data, including freeze-frame conditions, misfire counters, Mode $06 results, and technical service bulletins relevant to your 2020 Chevrolet Silverado-2500hd. After confirming the code, we verify causes with targeted tests—visual checks, smoke testing for EVAP leaks, fuel/air measurements, and road tests when appropriate. Find us at 5500 S State St, Murray, UT 84107. Have questions or need a convenient time? Schedule your appointment and we’ll prepare a clear repair plan with options.

We focus on facts, not guesses. Your visit begins with a quick intake to confirm symptoms and recent events (fuel stop, towing, or service). Next, we perform an OBD-II scan and review freeze-frame data to understand when and how the fault set. We check GM service information for known patterns, then conduct isolation tests as needed: EVAP smoke testing for small leaks, MAF and intake inspections, ignition and fuel checks for misfires, and live-data or Mode $06 analysis. You’ll receive documented findings and a written estimate before any repair. Ready to move forward? Schedule service and see current service specials online.

Several codes appear frequently on this truck. P0300 (random misfire) points to ignition or fuel issues; ignoring it can overheat and ruin the catalytic converter. P0442 (EVAP small leak) often traces to a loose cap or a small hose leak; left unaddressed, it can keep readiness monitors from setting and cause an inspection failure. P0101 (MAF performance) and P0171 (system too lean) affect drivability and fuel economy; dirty sensors or intake leaks are common. P0420 (catalyst efficiency) may follow prolonged misfires or fuel issues and can become costly if deferred. Bring your 2020 Chevrolet Silverado-2500hd to Larry H. Miller Chevrolet Murray in Murray for an accurate diagnosis — schedule service.