Safety inspection laws can vary substantially between states and even municipalities, with some states requiring stringent safety check-ups and others requiring no inspections or emissions-only. If you live in an area requiring more intense inspections, deferring maintenance on your vehicle can become a costly misstep.

Failing your safety inspection will often force you to correct any issues quickly, potentially leading to inconvenient or expensive repairs. At worst, a failed inspection may prevent you from legally registering your vehicle. If you have a safety inspection coming up, here are three ways that ignoring ongoing maintenance issues may cause you to fail.

1. Faulty Tires

While many drivers ignore them, tires are one of your vehicle's most important safety components. An old or balding tire can make your vehicle behave unpredictably or even dangerously in inclement weather, often causing an unexpected loss of traction on wet road surfaces. Faulty tires are particularly dangerous because they can often feel secure on dry surfaces, giving a false sense of confidence.

If your state or city requires a safety inspection, you should get in the habit of checking your tires fairly often. The penny test is a relatively good method to determine if your tires have sufficient remaining tread. However, you should also look for signs of bubbling or other visible indications of damage. Don't delay replacing or repairing tires below minimum tread depth or with other potential safety issues.

2. Bad Light Bulbs

Most states that conduct safety inspections will, at a minimum, check for proper bulb operation. Some cars may provide a warning light on the dash or infotainment system when a light bulb fails. If your vehicle doesn't have this feature, perform a check at least once or twice per month to ensure your bulbs are working. Use a helper to check for the proper operation of your brake lights.

While a failed light bulb might seem minor, you shouldn't wait until the last minute to replace it. In addition to being a safety hazard, lights can sometimes fail due to underlying wiring issues or problems with the bulb holder. Replacing your bulb before your safety inspection will give you time to address these issues instead of failing your inspection due to an easily avoidable problem.

3. Check Engine Lights

Your car's onboard diagnostics system (OBD-II) is closely related to your car's emissions equipment. As a result, error codes that trigger a check engine light will typically result in an automatic failure of safety, smog, and emissions checks. If your car has a visible check engine light, ignoring the problem will cause you to fail any upcoming safety inspections.

Note that the OBD-II system relies on a concept known as drive cycles. Clearing a code won't allow you to pass an inspection because certain readiness monitors will show incomplete drive cycles. In other words, any code that returns will inevitably result in a failed inspection, so you'll need to address the underlying issue to pass.

To learn more, contact a safety inspection service in your area.