Welcome to a new era in Car Mechanic Simulator 2021, where the game just got a little more realistic — and a lot more complex. With the introduction of fuses and expanded liquid handling, the devs have added a fresh layer of mechanical detail that brings this game even closer to real-world wrenching. Whether you’re a seasoned PC player or a console newcomer, this guide will walk you through the essential mechanics of fuses and fluids, how to handle them, and most importantly, how to avoid costly mistakes.
The Fuse Box: Small Parts, Big Problems
In older versions of CMS, if a car didn’t start, the diagnosis was usually a quick two-step: alternator or starter. That was it. But with CMS 2021, there’s now a third suspect — the fuse box.
Fuses and relays are now fully functional components, controlling electrical systems from the starter to the alternator, wipers, radio, and more. If something electrical isn’t working and you’ve already replaced the related part, your issue might be hiding inside the fuse box.
For example, a dead starter could be caused not by the starter itself, but by Relay A or B. The game doesn’t always tell you which fuse or relay controls what, so you’ll need to troubleshoot like a real mechanic: methodically and patiently.
And yes — if a relay or fuse is shot, you’ll need to replace it.
Liquid Management: Real Costs, Real Consequences
CMS 2021 now punishes sloppy work when it comes to fluids. If you remove a part connected to a fluid system — like a water pump, radiator, power steering reservoir, or brake caliper — without first draining it, the liquid spills out and you’re charged for the mess. It’s not just about realism; it’s about paying attention.
To drain liquids properly:
- Right-click to access Additional Tools.
- Select the Drain Tool.
- Hover over the appropriate component (radiator, reservoir, etc.).
- Hold the button — a comically large syringe will suck out the liquid.
- Done! No penalty, no charges.
This mechanic applies to power steering, coolant, brake fluid, and engine oil. The only fluid system that hasn’t been added (yet) is the fuel line — though future updates could very well bring it in.
Radiator Types: Watch for ‘Radiator C’
Some cars — especially older models — use Radiator C, which features a filler cap directly on the radiator. If your vehicle lacks a dedicated coolant reservoir, then Radiator C is where all coolant activity happens.
Important: Before removing a Radiator C, you must drain it. Failing to do so results in coolant spilling everywhere, and yep — you’ll be charged.
Newer cars tend to have a separate coolant reservoir, making the process more intuitive. But with Radiator C, there’s no shortcut — treat it with care.
Best Practices: Saving Money and Time
Here’s the winning strategy moving forward:
- Step 1: Pop the hood first thing.
- Step 2: Drain all the fluids.
- Step 3: Begin your diagnostic or teardown.
This mindset ensures you never get penalized for spilling fluids, and it keeps your repairs efficient. It’s a new habit worth building, especially with more systems being added to the game over time.
Treat the drain tool as your best friend at the start of every job. It takes seconds to use and saves you money every time. And if you’re a completionist or playing on Expert Mode, skipping this step can quickly become a costly oversight.
Fuses & Fluids = A New Layer of Realism
The addition of fuses and liquids might seem small on paper, but they dramatically change how you approach each job. You’re no longer just a part-swapping machine — you’re a problem-solver, an analyst, a true mechanic. Every bit of attention to detail now matters, and that’s a huge win for the game’s immersion.
If you’re just diving into CMS 2021, or returning after a break, this is the perfect time to embrace the challenge. Learn the systems, get efficient with your tools, and most importantly — stay clean, stay smart, and keep your credits intact.
And remember: always drain before you dismantle. Your wallet will thank you.
Thanks for tuning in — if this guide helped, don’t forget to like, subscribe, or support the channel. Peace out, and enjoy the grind!
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