That's great that you washed your car's body & under body to get the salt off.
I'm sure seeing a light on a dash afterwards was not a fun thing to find.
I recommend you get the vehicle scanned to see what code was set. This will give you the information of whether or not it was connected to the car wash or just happened to come on at this same time.
〉 Answered on Mar 10th, 2015 by Amy Mattinat, Owner and Author at Auto Craftsmen Ltd
Might be a coincidence, or you could've gotten something wet that shouldn't have been exposed to moisture.
〉 Answered on Mar 10th, 2015 by Gelina Aquilina, Service Advisor / Mechanic at