New Extended Hours Now Available

Why You Can’t Rely on Warning Lights to Diagnose Repairs

Posted on 06/24/18

When a vehicle isn't diagnosed properly it cannot be repaired correctly and that can lead to unhappy customers. Not all vehicle electronic or diagnostic issues cause a malfunction indicator lamp to light up on the dashboard. Implementing a pre- and post-repair diagnostic repair process using the asTech™ device to diagnose the full scope of electronic issues will allow your repair facility to properly diagnose and understand all of the damage present on the vehicle before repairs begin.

If you're simply using a visual inspection or the presence of an MIL to diagnose the repair issues, you may be setting yourself up for vehicle comebacks and dissatisfied customers.  

Why You Shouldn't Rely On MILs

Instrument cluster warning lights can be a starting place with vehicle diagnosis, whether it's a mechanical repair or a collision repair. However, these MILs cannot give precise insight into many symptoms a car will experience. The problem is that MILs don't cover all the potential problems that arise from a collision.

Here are a few more MIL myths.

Diagnostic Trouble Codes Without an MIL

Don't be fooled into thinking the vehicle is problem-free if a light isn't lit on the dash. Depending on the manufacturer, a whole gamut of diagnostic trouble codes (DTCs) can be present without turning on an MIL. This can be the case with an occupant classification system DTC or an ABS system code. Late-model cars with front and rear parking systems, cameras or radars may be inoperative, yet there are no warning lights illuminated.

A thorough diagnostic scan with an OEM factory scan tool or an asTechTM device can show fault codes set in modules. There might be a problem present, but you'll never know unless a comprehensive diagnostic procedure is completed.

A Great Quality Control Step

Even if there isn't an MIL illuminated, a full diagnostic post-scan test with an asTech™ device is perfect for quality control. As an example, many cars with tire pressure monitoring systems need to be driven a few miles before tire sensors register with the car. Has a technician neglected to program a sensor after a repair or is there a wiring problem for a module?

A post-repair diagnostic scan with the asTech™ device can detect concerns early – before the customer drives away in the vehicle only to return with a complaint.

Why an asTechTM Device Is the Perfect Solution

When your shop uses an asTechTM device, it makes it easy to fix vehicles correctly, even when there aren't any MILs present.

The technician begins the repair process with a complete vehicle scan using the asTechTM device. All modules are checked for DTCs whether there's a light on or not. From Airbag and ABS lights, to Check Engine lights, all DTCs are recorded and reported. The customer can be advised of anything unrelated to the collision repair, saving you headaches at the end of the repair.

Once the technician has completed the repairs, a final scan is done with the asTechTM device. The technician can confirm that all DTCs related to the repairs have been corrected and the customer is on their way, completely satisfied.