I was getting occasional CEL P0126s, so I decided to replace the thermostat on a 2006 Mazda5
1) Drained radiator from drain hole on driver's side of radiator - a little over 1 gal of fluid
2) Removed overflow tank (empty & clean) and all hoses from radiator neck for hand access
3) Did not remove tensioner belt as in manual - not needed
4) Thermostat has three 7mm bolts - used 3/8 ratchet with 1/4 adapter & 6" extension - fit perfectly. Removed 1 bolt from top, 2 bolts from bottom.
5) Thermostat has 2 hoses attached - 1 large, 1 small - these are pain to get off. I traced small hose to engine - removed small hose from engine(don't pull off hose with face under engine & mouth open
. With small hose removed, was able to bend large hose so that thermostat is under engine - then able to remove both the small & large hoses from the thermostat. Thishttps://www.amazon.com/dp/ (commissions earned) would really help in getting off the clamps.
6) Note that markings on hose - align with marks on thermostat. Attach large hose to thermostat under engine, then small hose. Push thermostat back to original location.
7) attach small hose to engine
8) bolt back thermostat - 2 from below, one from top
9) hook backup hoses & overflow tank
10) flush radiator
11) refill radiator & you're done
12) check for leaks
I hope this helps someone - no pictures - sorry
1) Drained radiator from drain hole on driver's side of radiator - a little over 1 gal of fluid
2) Removed overflow tank (empty & clean) and all hoses from radiator neck for hand access
3) Did not remove tensioner belt as in manual - not needed
4) Thermostat has three 7mm bolts - used 3/8 ratchet with 1/4 adapter & 6" extension - fit perfectly. Removed 1 bolt from top, 2 bolts from bottom.
5) Thermostat has 2 hoses attached - 1 large, 1 small - these are pain to get off. I traced small hose to engine - removed small hose from engine(don't pull off hose with face under engine & mouth open

6) Note that markings on hose - align with marks on thermostat. Attach large hose to thermostat under engine, then small hose. Push thermostat back to original location.
7) attach small hose to engine
8) bolt back thermostat - 2 from below, one from top
9) hook backup hoses & overflow tank
10) flush radiator
11) refill radiator & you're done
12) check for leaks
I hope this helps someone - no pictures - sorry