Reference
CTC cheat sheet
One-page printable reference. Keep it in your cab.
CARB Clean Truck Check
Reference v.2026-05 · cleantruckcheckmobile.com
Heavy-Duty Inspection & Maintenance (HD I/M) program
In scope (ALL must be true)
- GVWR > 14,000 lbs (manufacturer-rated)
- Fuel = diesel, alt-fuel, or hybrid
- Operates on CA public road (even if out-of-state registered)
Gasoline-only HD and ZEV are NOT in scope.
Which test?
| Diesel/hybrid MY ≥ 2013 | OBD |
| Alt-fuel MY ≥ 2018 | OBD |
| Pre-2013 diesel | Smoke Opacity + Visual |
| Pre-2018 alt-fuel | Smoke Opacity + Visual |
| No compliant OBD-II | Smoke Opacity + Visual |
Frequency
- Semi-annual (every 6 mo) — default
- Annual — non-commercial motorhomes, ag vehicles
- Four times per year starting Oct 2027 for most OBD-equipped vehicles
Deadline anchor: CA-reg → DMV expiration. Out-of-state → last digit of VIN.
Passing test may be submitted up to 90 days before deadline.
Exemptions (self-attested)
- Zero-emission (BEV, FCEV)
- Military tactical (13 CCR § 1905)
- Emergency vehicles (CVC § 165)
- Historical / Horseless Carriage plate
- Experimental permit (HSC § 43014)
- Out-of-state-registered motorhomes
- Engines certified to ULN ≤ 0.010 g/bhp-hr (through 12/31/2026)
No low-use, no small-fleet, no mileage exemptions.
Fees & enforcement
- Annual compliance fee: $32.13 (2026), CPI-adjusted
- Non-compliance can lead to CARB enforcement, DMV registration issues, or a Notice to Submit Testing
- Tampering or removed emissions equipment can create additional enforcement risk
- For penalty amounts and deadlines, verify current CARB guidance before advising a customer
Reporting
Owner reports each vehicle in CTC-VIS within 30 days of acquisition/disposition.
- Report: cleantruckcheck.arb.ca.gov
- VDECS retrofit list: ww2.arb.ca.gov/diesel/verdev/vt/cvt.htm
- CARB CTC help: (866) 634-3735 · hdim@arb.ca.gov
Out-of-state vehicles
CARB provides limited temporary operating options for some out-of-state vehicles. Verify current eligibility and timing directly with CARB before advising a customer.
On-site checks (operator)
- OBD: readiness monitors complete
- OBD: no obvious active/permanent faults
- OBD: VIN/eVIN match and report is not blank
- OBD: note recently cleared DTCs, incomplete monitors, or missing aftertreatment data
- If retrofit: verify CARB VDECS listing and customer documentation