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

Education posted on 10/18/18

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® Remote Diagnostic 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, but 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 comprehensive diagnostic scan with the asTech® Remote Diagnostic Device, which connects the vehicle to the OEM factory scan tool, 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, performing a full diagnostic service request with an asTech® Remote Diagnostic Device is perfect for quality control. As an example: without a scan there is no way to know if a technician neglected to program a sensor after a repair, or if there is a wiring problem for a module. Scanning with the asTech® Remote Diagnostic Device can prevent these issues from going undiscovered.

post-repair diagnostic scan with the asTech® Remote Diagnostic Device can detect concerns early – before the customer drives away in the vehicle only to return with a complaint.

Why an asTech® Device Is the Perfect Solution

When your shop uses the patented asTech® Remote Diagnostic Device, it makes it easy to fix vehicles correctly, even when there aren’t any MILs present.

The technician, before teardown, begins the repair process by ordering an asTech® diagnostic service request. 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 diagnostic service request is completed with the asTech® Remote Diagnostic Device. The technician can confirm that all DTCs related to the repairs have been corrected and the customer is on their way, completely satisfied.

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