Was wondering if anyone has any experience with this?

I purchased my 2011 Tribute last January, have had it for about 16 months. I drive a lot, but have kept up on all of my maintenance needs, oil changes, etc. and all have been done through my dealership.

Today I picked up my Tribute after having work done to the rear axel which was apparently leaking. Within 30 minutes of getting in the car and heading home the wrench warning light came on. My car seems to be driving completely normal, but I'm concerned that this can mean a serious problem, based on the feedback/experiences I've seen posted.

This isn't the first time I've had work done, covered by my warranty, where a light (usually check engine) has gone off soon after my service. It's making my highly doubt the trustworthy-ness and competence of my Mazda dealership.

Anyone know what may cause the light to go on? I plan to call the dealership first thing in the morning and have them take a look; I don't want to get sucked into paying again for something they most likely did. Any insight is helpful, thank you!