Parts for your 2020 Suzuki Splash-Thermostat housing

2020 Suzuki Splash Thermostat Housing — what it does and how to look after it

Based on technical references including the Suzuki Splash/Ritz Service Manual (Cooling System section), the Suzuki K10B/K12B Engine Workshop Manual, and OEM parts catalogues used by dealerships and aftermarket suppliers, the 2020-registered Suzuki Splash is fitted with a thermostat and a bolt-on thermostat housing. So yes, a thermostat housing is relevant and used on this vehicle.

On the Splash’s K-series engines, the thermostat housing anchors the thermostat, routes coolant from the cylinder head to the radiator, and often carries the coolant temperature sensor and bleed points. Its job is to help the engine warm up quickly, then hold temperature steady under Aussie and Kiwi conditions—whether it’s peak-hour crawl in Brisbane or a chilly start in Dunedin.

A sound thermostat housing keeps the cooling system sealed and pressurised, prevents leaks, and ensures the heater works a treat. Most Splash housings are a moulded composite/plastic assembly with an O-ring seal and hose connections. Over time, heat cycles and coolant chemistry can make the plastic brittle and the seals flatten, which is why periodic checks matter.

For servicing, stick with the correct thermostat temperature spec for the Splash engine and refresh coolant at the interval in the service schedule. Inspect the housing for hairline cracks, white crusty deposits, staining around joints, or dampness under the outlet neck. If the vehicle is around the 8–10 year mark or showing any leak, warping, or sensor issues, replacing the housing (and thermostat) together is smart preventative maintenance. Always use quality coolant that meets Suzuki Super Long Life Coolant specs, and new O-rings/gaskets.

Quick tips when replacing the 2020 Suzuki Splash thermostat housing:

• Match the part to the engine (K10B 1.0 litre or K12B 1.2 litre) and thermostat temperature rating.
• Clean gasket faces carefully, don’t gouge the alloy head.
• Torque the housing bolts evenly to spec, overtightening can crack plastic.
• Refill with fresh 50/50 premix coolant, bleed air, confirm heater is hot and fans cycle correctly.
• Scan for codes like P0128 (coolant temp below thermostat regulating temperature) after road test.

Watch for these signs the thermostat housing or thermostat needs attention:

1. Coolant weep or a sweet smell near the housing or lower radiator hose.
2. Slow warm-up, fluctuating temp gauge, or poor cabin heat.
3. Overheating at idle but cooler on the open road.
4. Visible cracks, chalky residue, or distorted hose connections.

Popular questions about 2020 Suzuki Splash thermostat housing

Where is the thermostat housing on a 2020 Suzuki Splash?

It’s mounted at the cylinder head outlet where the lower radiator hose connects, typically on the gearbox side of the engine bay. Follow the main hose from the radiator back to the engine, the hose clamps onto the housing.

On K12B/K10B engines it’s a compact plastic assembly that may also hold a coolant temp sensor and bleed screw.

What symptoms point to a bad thermostat housing or thermostat?

Look for coolant stains or dampness around the housing, slow warm-up, erratic temperature readings, or overheating in traffic. A thermostat stuck open can trigger a P0128 code, stuck closed risks overheating.

Heater going cold at speed and hot at idle can indicate air in the system or a leak at the housing letting air in.

Should the housing be replaced with the thermostat?

Often, yes. The Splash’s plastic housing can become brittle with age, and its O-ring flattens. Replacing the housing and thermostat together reduces repeat labour and helps ensure a long-lasting seal.

If the housing is perfectly sound, you can replace just the thermostat and seal—but inspect closely and don’t reuse old O-rings.