Parts for your 2019 Suzuki Splash-Thermostat

2019 Suzuki Splash thermostat — purpose, servicing and when to replace

Per Suzuki’s factory workshop information for the Splash/Agila platform (K10B 1.0, K12B 1.2 and D13A 1.3 DDiS) and the Suzuki electronic parts catalogue for those engines, this model uses a conventional, wax‑pellet engine‑coolant thermostat mounted in a housing at the cylinder head water outlet. Major technical catalogues from established cooling specialists (e.g., Tridon, Gates, Mahle) also list direct‑fit thermostats for Splash engines from this generation. That means a thermostat is absolutely fitted and relevant on a 2019‑registered Suzuki Splash.

The thermostat’s job is to help the Splash warm up quickly and then hold a steady operating temperature. It stays closed when the engine is cold, so the coolant recirculates within the block and head for a faster warm‑up, better fuel economy and lower wear. Once the coolant reaches its calibrated temperature (typically in the mid‑80s °C, full open in the 90s), the thermostat opens and lets coolant flow through the radiator to shed heat. If it sticks shut, the engine can overheat, if it sticks open, the engine may run too cool, the heater goes lukewarm and fuel use can climb.

As part of routine servicing on a 2019 Suzuki Splash, it’s sensible to check for thermostat‑related clues and refresh the cooling system on schedule. Many owners replace the thermostat preventatively around the 8–10 year/150,000 km mark, or sooner if symptoms show up. When replacing, a new housing seal/O‑ring is a must, coolant should be drained and refilled with the correct long‑life, silicate‑free coolant, and the system bled to remove air. After replacement, confirm the radiator hoses warm in sequence and that the cabin heater is toasty at idle.

• Common signs it’s time: slow warm‑up, fluctuating temp gauge, poor heater performance, fans running more than usual, or coolant boiling/overflowing.
• Good practice: replace the thermostat when doing major cooling work (radiator, water pump, timing‑chain cover service) to save on duplicated labour.
• Tools and tips: have fresh hose clamps ready, clean the gasket surfaces carefully, and torque the housing evenly to avoid leaks or warping.
• Aftercare: use a coolant hydrometer/refractometer to verify mix ratio, inspect for leaks after the first few drives, and recheck the expansion bottle level.

Looked after this way, the Splash’s thermostat quietly keeps temperatures steady through Aussie heat and cooler Kiwi mornings, helping the little Suzuki feel crisp, efficient and reliable for the long haul.

Popular questions about the 2019 Suzuki Splash thermostat

Where is the thermostat located on a 2019 Suzuki Splash?

It sits in a small alloy housing at the cylinder head’s water outlet, typically on the gearbox side of the engine bay. Follow the upper radiator hose back to the engine — where that hose meets the alloy housing is where you’ll find the thermostat tucked inside.

On K10B/K12B petrol engines the housing is compact and secured with a couple of bolts. The unit is serviceable from above after removing the intake ducting for space. Always start with a cold engine and drain enough coolant to avoid spillage under the bonnet.

What temperature thermostat does the Splash use?

Suzuki specifies a thermostat that begins to open in the mid‑80s °C range and is fully open in the low‑to‑mid‑90s °C, depending on engine variant. That calibration gives brisk warm‑up and stable running without constant fan cycling.

If buying a replacement, match the opening temperature printed on the part or in the catalogue to your engine code. Quality brands list the opening temperature clearly, avoid “colder” race thermostats for road use as they can increase fuel use and reduce heater performance.

Can you drive a Splash with a bad thermostat?

Not recommended. A stuck‑closed thermostat can cause rapid overheating and serious engine damage. A stuck‑open thermostat won’t usually overheat, but it can keep the engine too cool, hurting fuel economy and emissions and leaving you with a weak heater on winter mornings.

If you must drive, keep it short, watch the temp gauge like a hawk, and avoid traffic. Better plan: park it, let the engine cool completely, and sort the thermostat and coolant refill/bleed before the next trip.