Many modern-day vehicles can have up to 100 modules that need to communicate with one another in order to function properly. This emphasizes the importance of pre- and post-repair scans, according to Duane “Doc” Watson, Bosch technical trainer, who discussed the topic in a recent Automotive Service Association (ASA) webinar.
“Dash lights won’t tell you a complete story,” Watson explained. “The potential for hidden electrical damage in a modern system is possible. The pre- and post-scan procedures … will help you get a damaged vehicle back to a safe, pre-accident condition.”
And there’s money to be made in-house, he said, as many auto manufacturers now require or recommend pre and post scans to ensure the repair is done properly, including GM, Toyota, Honda and Nissan.
However, Watson noted that knowing when a scan tool is required is a bit murky, and technicians should use sound judgment for each vehicle that comes in for a repair. Factors to consider, he suggested, are the age of the vehicle, the extent and type of damage and what technologies the vehicle is equipped with.
While there is no industry standard for payment yet, Watson said repair shops are getting paid for about 70 percent of the pre- and post-repair scans, but it depends on a few factors.
“Having a printed or a digital report for each scan is key to getting paid,” he explained. “Some insurers pay for them without issue; some require some negotiation, and rates can vary by area, scan method and even the insurer.”
If you’re thinking of performing scans in-house, Watson said a shop will need the following equipment:
- A quality scan tool that’s capable of accurate and complete pre- and post-scans with accompanied diagnostics reports;
- A battery maintainer or a high-end battery jump box—a vehicle with a weak battery can’t be scanned accurately; and
- Copies of the OEM position statements regarding how to properly conduct the procedure.
He also noted that the insurance company will most likely ask for the OEM position statements as well as the pre- and post-repair scan results, if a shop wants to get paid for the work.
But performing pre and post scans in-house requires more than the tool itself. There are test preparations a shop will need to do to ensure getting the best scan results.
“Be sure the battery has at least 12.6 volts before testing,” Watson cautioned. “Failure to do so may result with inaccurate test results due to low battery voltage and giving you erroneous codes. We highly recommend that you use a fully charged battery booster as needed or use a battery maintainer. Do not use a battery charger. A battery charger can influence the CAN [Controller Area Network] bus on a vehicle while doing DTC [Diagnostic Trouble Code] scans.”
Watson also warned of using old-school battery chargers, stating the output voltage could spike, causing erroneous or false codes.