--- title: Smog Check Came Back Not Ready: Readiness Monitors url: https://xpressoilandlube.com/problems/smog-check-not-ready/ business: Xpress Oil & Lube (Xpress Oil & Lube Center) shops: Reno Northwest: 6100 Mae Anne Ave, Reno, NV 89523, (775) 787-1000, Mon-Fri 8 am-5 pm, Sat 8 am-4 pm, Sun closed; Reno South: 4993 Longley Ln, Reno, NV 89502, (775) 828-6996, Mon-Fri 8 am-5 pm, Sat 8 am-3 pm, Sun closed; Carson City: 1861 E College Pkwy, Carson City, NV 89706, (775) 883-5823, Mon-Fri 8 am-5 pm, Sat 8 am-4 pm, Sun closed; Gardnerville: 1293 US Hwy 395 N, Gardnerville, NV 89410, (775) 301-5912, Mon-Fri 9 am-5 pm, Sat 9 am-3 pm, Sun closed type: Drive-in oil change and vehicle maintenance, no appointment needed, since 1983 --- Today's coupons - $10 off full-service oil change - $5 off smog check - $25 off transmission fluid service [See all coupons](https://xpressoilandlube.com/coupons/) - [Home](https://xpressoilandlube.com/) - [Problems](https://xpressoilandlube.com/problems/) - Smog check came back not ready # The smog check came back not ready A not-ready result means one or more of the car's onboard self-tests, called readiness monitors, has not finished since the computer was last cleared, often after a battery change or a repair. Drive normally for several days to complete them, then come back for the test. ★★★★★ 4.7 stars from 952 Google reviews This week General guidance for this symptom. A warning light that is flashing or an overheating engine: stop driving and call. ## Likely causes - A battery was disconnected or replaced Disconnecting power clears the computer's memory, including the monitor results. They start again from zero. [Battery check](https://xpressoilandlube.com/services/battery-check/) - Codes were cleared after a repair Clearing a check engine light with a scan tool also clears readiness. If the original fault is fixed, the monitors complete with normal driving. [Smog check and emissions test](https://xpressoilandlube.com/services/smog-check/) - Short trips only Some monitors, especially the evaporative system and catalyst monitors, need specific conditions: a cold start, steady highway speed, a certain fuel level or a long idle. A car that only does short trips across town may not hit them. [Smog check and emissions test](https://xpressoilandlube.com/services/smog-check/) - An underlying fault keeps a monitor from finishing If a fault is still present, the related monitor may never complete. A repair shop with a scan tool can see which one is stuck and why. [Multi-point maintenance check](https://xpressoilandlube.com/services/maintenance-check/) A not-ready result is not a failure in the usual sense. In Nevada's testing area, newer vehicles are checked through the onboard diagnostic system, and that system has to report that its own checks are complete. A recently disconnected battery, a code cleared by a scan tool, or a repair that reset the computer wipes those results, and the car needs time on the road to run them again. The EPA describes this as the OBD system confirming that emissions components were monitored. ## Helping the monitors finish - Keep the fuel tank between about a quarter and three quarters full; some evaporative monitors need that range. - Start the car cold at least once a day, after it has sat overnight. - Include some steady highway driving, for example a run on I-80 or US-395 at a constant speed. - Include some city driving with stops and a few minutes of idle. - Repeat over several days. Some monitors finish in one drive, others take a week of mixed driving. Your owner's manual or the manufacturer may publish a specific drive cycle. Following it can speed things up. Our [readiness monitors guide](https://xpressoilandlube.com/guides/smog-check-readiness-monitors/) goes deeper. ## The Nevada rules that apply Smog checks are required at registration renewal for gasoline vehicles 1968 and newer and diesels up to 14,000 lb in the Washoe County and Clark County testing areas. New vehicles are exempt for their first three registrations, and hybrids for their first five model years (Nevada DMV emission program). Carson City, Douglas and Lyon County registrations do not require a test. A passing test is valid for 90 days, so you do not need to cut it close. Test as soon as the monitors are ready, then renew. If your renewal date is near, the DMV page explains the options, and our [renewal steps guide](https://xpressoilandlube.com/guides/nevada-registration-renewal-steps/) lays out the order. ## What our Reno service centers do Our Mae Anne and Longley Lane service centers run the [smog check](https://xpressoilandlube.com/services/smog-check/). When a car comes back not ready, we tell you which monitors were incomplete, so you know what kind of driving to do. You can come back without an appointment when you are ready. If a monitor will not complete because of a fault, that is repair shop territory. We do not do emissions repairs. Once the repair is done and the car has been driven enough, drive back in for the test. ### Sources - [dmv.nv.gov/emission.htm](https://dmv.nv.gov/emission.htm) (Nevada DMV Emission Control Program: testing areas, exemptions, 90-day validity of a passing test; read 10/15/26) - [epa.gov/state-and-local-transportation/vehicle-emissions-on-board-diagnostics-obd](https://www.epa.gov/state-and-local-transportation/vehicle-emissions-on-board-diagnostics-obd) (EPA: on-board diagnostics, the check engine light and emissions faults; read 10/15/26) ### Your service center: Reno Northwest - Call [(775) 787-1000](tel:+17757871000) Mon-Fri 8 am-5 pm, Sat 8 am-4 pm, Sun closed - Address 6100 Mae Anne Ave, Reno, NV 89523 [Directions](https://www.google.com/maps/dir/?api=1&destination=6100+Mae+Anne+Ave%2C+Reno%2C+NV+89523&destination_place_id=ChIJ3dFA7yBEmYARYg1CtQTi_Bk) ### Related - [Failed a smog check](https://xpressoilandlube.com/problems/failed-smog-check/) - [Check engine light on](https://xpressoilandlube.com/problems/check-engine-light-on/) - [Readiness monitors: why a smog check can be 'not ready'](https://xpressoilandlube.com/guides/smog-check-readiness-monitors/) - [Before a smog retest](https://xpressoilandlube.com/checklists/before-a-smog-retest/) - [Smog check and emissions test](https://xpressoilandlube.com/services/smog-check/) Drive in. No appointment. Drive out. Locally owned in Northern Nevada since 1983. No appointment, no pressure: we tell you what the inspection found and you decide. [About us](https://xpressoilandlube.com/about/) ## What we do about it [### Smog check and emissions test Learn more](https://xpressoilandlube.com/services/smog-check/)[### Fuel system cleaning Learn more](https://xpressoilandlube.com/services/fuel-system-cleaning/)[### Multi-point maintenance check Learn more](https://xpressoilandlube.com/services/maintenance-check/) ## Questions people ask Still have a question? Call your service center or drive in; there is no appointment to make. ### Is not ready the same as failing? It is not a pass, but it is not an emissions failure either. The car simply has not finished its self-tests. ### How long does it take for monitors to be ready? It varies by car and monitor. Many are ready after several days of mixed driving; some take longer. ### Can I pass with one monitor not ready? Federal guidance allows a limited number of incomplete monitors depending on the model year. The test station's equipment applies the rule. ### I just replaced my battery. Should I wait to smog it? Yes. Drive normally for several days first so the monitors can complete.