RESET SERVICE MINDER also what type of brake fluid do you use?

Karen, the garage that did the fluid change should have done this for you, it is part of the service. Can not find your exact model, will post links to similar.
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Instructions for Resetting Brake Fluid Service Indicator
DIY resetting service due lights
DIY 335 Service Light Reset

Most is just an oil and oil filter change. What Andrew said should be checked. Most don't do it. Unless it is obvious..

A13 is broken down to A, 1, and 3.

A means you have to change your oil.
1 means you need your tires rotated.
3 means you need to change your transmission fluid.

It's a maintenance minder code. You could look in the owners manual and decipher the code. You will probably find something like this:

B = Replace engine oil and oil filter; inspect brakes, hoses and lines; check parking brake adjustment; inspect tie rod ends, steering gear box, boots, suspension components, driveshaft boots, all fluid levels and condition of fluids, exhaust system, fuel lines and connections

1 = Rotate tires

3 = Replace transmission fluid (for A/T only)

This is your vehicles maintence minder system letting you know you are 100 miles over due for an oil change. If you had an oil change performed recently and they did not reset the maintenece minder go off the rec. mileage sticker on the windshield. In answer to your question code A is the main code for an oil service. Often times the main letter codes will be followed by sub-codes that will appear as numbers following the letter. Exp.. A-1, B-1, B-2... The Dealership can clarify what each series of codes and sub-codes means in regards to the needed service. Best piece of advice when the maintenence minder hits 15% oil life remaining bring the car in for service. And check the oil at least once a month.

From Owner's Link:

Maintenance Minder B Scheduled Maintenance
Recommended service for your 2006 Honda Ridgeline:

Replace engine oil and oil filter
Rotate tires
Inspect front and rear brakes
Check parking brake adjustment
Inspect tie rod ends, steering gear box, and boots
Inspect suspension components
Inspect driveshaft boots
Inspect brake hoses and lines (including ABS)
Inspect all fluid levels and condition of fluids
Inspect exhaust system#
Inspect fuel lines and connections#

Adjust the valves during services A, B, 1, 2, or 3 if they are noisy.

Maintenance Minder 6 Scheduled Maintenance
Recommended service for your 2006 Honda Ridgeline:

Replace VTM-4 rear differential fluid: Driving in mountainous areas at very low vehicle speeds or trailer towing results in higher level of mechanical (shear) stress to fluid or frequently fully loaded. This requires differential fluid changes more frequently than recommended by the Maintenance Minder. If you regularly drive your vehicle under these conditions, have the differential fluid changed at 7,500 miles (12,000 km), then every 15,000 miles (24,000 km).

That wrench is a maintenance minder indicator lettting you know that your oil's service life is at 15%, not that the level or amount is low. Have your oil changed and have the maintenance minder light reset.

Got B12 service minder.
B12:
B:
Replace engine oil and oil filter, Rotate tires, Inspect front and rear brakes, Check parking brake adjustment, Visually inspect tie rod ends, steering gear box, and boots, Visually inspect suspension components, Visually inspect driveshaft boots, Visually inspect brake hoses and line (including ABS), Visually inspect all fluid levels and condition of fluids, Visually inspect exhaust system, Visually inspect fuel lines and connections

1:
Rotate tires
2:
Replace air cleaner element (If you drive primarily in dusty conditions, replace every 15,000 miles (24,000 km).
Replace dust and pollen filter
If you drive primarily in urban areas that have high concentrations of soot in the air from industry and from diesel-powered vehicles, replace every 15,000 miles (24,000 km).
Inspect drive belt

Hold trip reset button down then turn key on but do not crank engine over light maint. light will go off after a couple of second

THIS IS HOW YOU RESET IT HAPPY HOLIDAYS

this is your maintence minder code.
A- oil change
B- oil change brake check and adjust
1-tire rotation
2-replace engine and cabin air filters
3- replace transmission fluid