Thermostat M270 for Mercedes-Benz

turbo petrol engine. Restores correct warm up time and stable operating temperature, helps protect against overheating and poor heater performance. Sold per unit, variant specific as supplied with housing and sensor where applicable.

What this is / isn’t:
Included: 1× thermostat assembly

Important: Match by VIN and engine code M270. Transverse models can use different housings, outlet angles or electrical connectors by year and market. Some trims share components with related M274 or M282 families, always confirm by OE part number.

Key Features:

• Precise temperature control: OE matched opening temp and flow for stable engine and cabin heat.

• Integrated housing and seal: Direct bolt on replacement to minimise leaks and comeback repairs.

• Correct sensor or actuator logic: Works with the ECU for accurate warm up and efficiency.

• Durable materials: High temp plastics and elastomers resist glycol and heat cycling.

• Exact fitment: Factory mounting points for a no mod install.

Compatibility:
Vehicles equipped with the M270 inline 4 turbo, match by VIN or OE:

• A Class W176 A180, A200, A250

• B Class W246, W242 B180, B200, B250

• CLA Class C117, X117 CLA180, CLA200, CLA250

• GLA Class X156 GLA200, GLA250
  Note: Longitudinal C Class models typically use M274, check your VIN to avoid mismatch.

Options, engine or sensor variations:

• Standard M270 thermostat → electronic assisted stat with housing.

• Model year revisions → later cars may have updated connector or outlet, verify before ordering.

• Market or emissions variants → confirm heater outlet routing and hose size.

Typical OE reference families, guide only:
A270-200-…, A270-203-…, supersessions vary by year and market.
Always order by the exact OE part number on your vehicle or confirm via VIN.

Symptoms of a faulty thermostat:

• Slow warm up, temperature gauge low or fluctuating.

• Overheating at idle or in traffic.

• Weak cabin heat, fault code P0128 or similar temperature errors.

• Coolant seepage at housing, dried crust around joints.

Installation notes, pro tips:

• Work on a cold engine. Drain coolant to below the housing level.

• Replace the seal or O ring, clean mating faces, torque bolts evenly to spec.

• Refill with Mercedes approved coolant, MB 325.x spec, bleed the system thoroughly.

• Verify fan operation and hose temperatures on first heat cycle, clear stored codes after a road test.

• Inspect adjacent hoses, clamps and plastic tees for age related brittleness.

What’s included / not included:
✅ 1× Thermostat assembly with housing and seal, sensor or actuator if supplied
❌ Coolant, hoses, clamps, water pump, radiator, extra sensors, hardware

Q&A
Q1: How do I confirm I have the M270 engine?
Check the VIN data card or engine stamp. M270 is used in transverse A, B, CLA and GLA models. Your VIN will map to the exact part number.
Q2: Do I need coding after replacement?
No coding is usually required. Clear fault codes and verify operating temperature with a scan tool.
Q3: Which coolant should I use?
Mercedes coolant meeting MB 325.x specification, mixed to the correct ratio for your climate.
Q4: Should I change anything else at the same time?
Consider a coolant service, inspect hoses and clamps, and replace any brittle plastic fittings.

Why choose TOParts:
OE grade engine components for Mercedes Benz with precise fitment, correct specs and long term reliability, trusted by panel shops and independent Mercedes specialists across South Africa.