Chill Mode is openpilot's standard driving state: your car follows the vehicle ahead, maintains your set speed, and leaves all braking decisions to conventional cruise control logic rather than the camera-based driving model. It's the default mode after a fresh install and the state your car returns to whenever Conditional Experimental Mode determines that conditions are straightforward enough for simple, predictable speed control.
The Big Idea
Chill Mode is the "relaxed highway cruising" half of openpilot's two-mode system, where speed control behaves like traditional Adaptive Cruise Control instead of relying on the AI driving model to interpret traffic lights and stop signs.
Every car running openpilot with gas and brake control (openpilot longitudinal) has two fundamentally different ways of managing your speed. In Chill Mode, the system uses proven Adaptive Cruise Control logic: it tracks your set speed, follows the car ahead at a safe gap, and slows down or speeds up based on radar and basic distance calculations. It doesn't try to interpret what the camera sees beyond lane keeping. Think of it as a competent highway cruise control, reliable, predictable, and well-tested.
Experimental Mode is the opposite end of the spectrum. It hands speed control to the driving model's neural network, which processes the raw camera feed and attempts to make human-like decisions: slowing for red lights, stopping at stop signs, and reacting to complex intersections. This is powerful but imperfect, which is why it's labeled "alpha quality."
Chill Mode exists because not every driving situation benefits from end-to-end AI decision-making. On a clear highway with no traffic lights, there's nothing for the AI to interpret. Simple cruise control logic is smoother, more predictable, and less likely to brake unexpectedly for shadows or distant objects. The name "Chill" captures this perfectly: it's the mode where you and the car can both relax.
💡 Tip: Not to be confused with the "Relaxed" driving personality. Chill Mode is a driving mode that determines how your car handles gas and braking decisions (conventional cruise control vs. AI-driven). The "Relaxed" personality is a following profile that adjusts how closely you follow the car ahead. You can use the Relaxed personality while in either Chill Mode or Experimental Mode.
Key Terms (Plain English)
Here's a quick reference for the terms you'll encounter throughout this page.
| Term | What it means |
|---|---|
| Chill Mode | The standard driving state where speed control uses conventional Adaptive Cruise Control logic. Your car follows the vehicle ahead and maintains your set speed without interpreting traffic lights or stop signs. |
| Driving personality | A separate axis of control (Traffic, Aggressive, Standard, Relaxed) that adjusts following distance and acceleration smoothness. Personalities work within both Chill Mode and Experimental Mode. |
| Experimental Mode | The AI-driven driving state where the camera-based model controls gas and braking, attempting to react to traffic lights, stop signs, and complex road situations. |
| Longitudinal planner | The part of the system that decides when to accelerate and brake. In Chill Mode, it runs in "Adaptive Cruise Control" (Adaptive Cruise Control) mode. In Experimental Mode, it runs in "blended" mode where the AI model's predictions also influence braking. |
| openpilot longitudinal | When openpilot directly controls your car's gas and brakes using its own software, rather than relying on your car's built-in cruise control system. The Chill Mode vs. Experimental Mode distinction only exists when this is active. |
Where You'll See It
Chill Mode shows up in two places: the offroad home screen and the on-road driving screen.
On-Road Driving Screen
If you have Conditional Experimental Mode enabled with its Status Widget turned on, a small widget appears near the driver monitoring icon while driving. When the system is in Chill Mode, this widget displays an animated chill mode icon with a black border. When the system switches to Experimental Mode for any reason, the icon and border color change to reflect the specific trigger.
The driving path's edge color also reflects your current mode:
- Black edges: Chill Mode (standard engaged driving). The exact shade of green depends on your selected color theme.
- Orange edges: Experimental Mode is active
- Yellow edges: You manually overrode Conditional Experimental Mode back to Chill Mode
Offroad Home Screen
On the home screen (the main offroad screen you see when the car is parked), there's an Experimental Mode button on the right side. When Experimental Mode is off, this button displays "CHILL MODE ON" with a couch icon on a green-to-blue gradient background. Tapping it navigates to the Toggles settings panel and expands the Experimental Mode toggle where you can switch modes.
Steering Wheel Button Background
The main on-road button (your steering wheel or custom icon) has a black background during Chill Mode, compared to an orange background when Experimental Mode is active.
How It Works (High Level)
Chill Mode is the "off" state of Experimental Mode, and there are three different ways the system enters it.
Path 1: Conditional Experimental Mode Reverting Automatically
This is the most common way drivers experience Chill Mode in daily use. When Conditional Experimental Mode is enabled (which it is by default), it continuously monitors your driving conditions. When none of its trigger conditions are met, the system reverts to Chill Mode. Specifically, the system returns to Chill Mode when:
- Your speed rises above the configured speed thresholds
- You're no longer following a slower or stopped vehicle
- Your turn signal turns off (or the system detects an open lane beside you)
- You've passed a navigation intersection or turn
- The curve you were driving through straightens out
- The driving model no longer predicts a stop ahead
- Speed Limit Controller has found a speed limit (if its fallback was triggering Experimental Mode)
Each of these is simply the clearing of a corresponding trigger condition. Once every condition clears, the status returns to 0, and the longitudinal planner switches back to conventional Adaptive Cruise Control logic.
Path 2: Default After Fresh Install
When you first set up your device, two key settings start in the "off" position. The first, ExperimentalModeConfirmed, defaults to Off, meaning you haven't yet acknowledged the Experimental Mode warning. The second, ExperimentalLongitudinalEnabled, also defaults to Off for cars that need it to unlock openpilot gas and brake control. Until you explicitly enable and confirm Experimental Mode through the settings, your car always drives in Chill Mode.
Path 3: Manually Disabling Experimental Mode
You can toggle Experimental Mode off at any time through the Toggles settings panel. You can also tap the steering wheel icon on the driving screen while openpilot is engaged. When Conditional Experimental Mode is not active, this directly flips between Chill Mode and Experimental Mode.
Mode State Reference
These two modes represent fundamentally different approaches to controlling your car's speed.
| Property | Chill Mode | Experimental Mode |
|---|---|---|
| Braking at red lights | No. Won't react to traffic lights. | Attempts to, but isn't guaranteed. |
| Braking at stop signs | No. Won't react to stop signs. | Attempts to, but isn't guaranteed. |
| Default on fresh install | Yes | No |
| Following the car ahead | Yes, using radar and distance calculations | Yes, with additional model-based predictions |
| Longitudinal planner mode | Adaptive Cruise Control (speed tracking with lead following) | Blended (model-driven acceleration and braking) |
| Path edge color | Green (shade varies by theme) | Orange |
| Smoothness | Generally smoother and more predictable | Can be jerkier in complex or ambiguous situations |
| Speed control approach | Conventional Adaptive Cruise Control logic | AI driving model's end-to-end predictions |
| Speed source | Your set speed (cruise control buttons) | Your set speed as upper bound; the model may drive slower based on what the camera sees |
| Steering (lateral control) | Identical in both modes | Identical in both modes |
| Steering wheel button background | Black | Orange |
⚠️ Warning: Neither mode is a substitute for driver attention. Chill Mode won't stop for traffic lights or stop signs. Experimental Mode attempts to but isn't reliable. You must always be ready to brake yourself.
What's Identical in Both Modes
Steering works exactly the same way regardless of which mode you're in. Always On Lateral, lane centering, lane changes, and all other steering behaviors are completely unaffected by the Chill Mode vs. Experimental Mode distinction. The mode only changes how gas and braking are handled.
Curve Speed Controller also works the same in both modes. It adjusts your target speed for upcoming curves based on curvature data, operating independently of the mode selection. Speed Limit Controller similarly adjusts your set speed based on posted limits in either mode. Your chosen driving personality (Traffic, Aggressive, Standard, or Relaxed) also applies in both modes, governing following distances and acceleration smoothness.
Conditional Experimental Mode: The Primary Mode Manager
For most FrogPilot drivers, Conditional Experimental Mode is the system that decides when you're in Chill Mode and when you're not.
Conditional Experimental Mode ships enabled by default. When it's active, Chill Mode becomes your baseline cruising state, and the system automatically elevates to Experimental Mode only when specific trigger conditions are met. Think of Chill Mode as "home base" that you always return to once the situation that required extra caution has passed.
How Triggers Affect Mode State
Conditional Experimental Mode checks a prioritized list of conditions roughly 20 times per second. The first matching condition activates Experimental Mode. When no conditions match, you stay in (or return to) Chill Mode.
| Priority | Trigger Condition | Enters Experimental Mode When... | Reverts to Chill Mode When... |
|---|---|---|---|
| 1 | Curve detection | Road curvature has been detected for roughly 1 second | The road straightens out (filter decays) |
| 2 | Navigation approach | You're nearing an intersection or turn on your route | You pass the intersection or turn |
| 3 | Slow/stopped lead | The car ahead is much slower or stopped (detected for roughly 1 second) | The lead speeds up or disappears |
| 4 | Speed Limit Controller fallback | Speed Limit Controller can't find a speed limit and its fallback is set to Experimental Mode | A speed limit is found |
| 5 | Speed threshold (no lead) | You're driving below your configured speed with no car ahead | Your speed rises above the threshold |
| 6 | Speed threshold (with lead) | You're following a car below your configured speed | Your speed rises above the threshold or the lead disappears |
| 7 | Stop prediction | The driving model predicts a stop ahead | The model's stop prediction clears |
| 8 | Turn signal | Your blinker is on below the signal speed threshold and no open lane is detected | You cancel the signal or exceed the speed threshold |
Manual Override Cycling
Even with Conditional Experimental Mode active, you can manually override the automatic mode selection by tapping the steering wheel icon on your driving screen. The tap cycles through three states:
- Currently in Chill Mode (status 0): Tap to force Experimental Mode on (status 2)
- Currently in Experimental Mode (status 3+): Tap to force Chill Mode (status 1)
- Currently overridden (status 1 or 2): Tap to return to automatic control (status 0)
The status widget's border turns yellow when you've manually forced Chill Mode, letting you know the automatic system is paused. Tapping again returns to automatic control.
Status Indicators
The on-road status widget and path colors give you instant visual feedback about your current driving mode.
When Conditional Experimental Mode's Status Widget is enabled, you'll see a small icon near the driver monitoring camera icon. Here's what each visual state means:
| Border | Icon | What it means |
|---|---|---|
| Black |  | You're in Chill Mode. No trigger conditions are active. Standard Adaptive Cruise Control is handling your speed. |
| Orange |  | Experimental Mode is active. The AI driving model is handling gas and braking decisions. The specific trigger icon tells you why. |
| Yellow | | You manually overrode Conditional Experimental Mode to stay in Chill Mode. The automatic system is paused until you tap the icon again. |
When the widget shows the chill mode icon with a black border, everything is running in the straightforward, predictable mode. No special braking decisions are being made based on what the camera sees.
Interactions With Other FrogPilot Features
Chill Mode is the baseline state that many other FrogPilot features operate within. Most of them work identically regardless of which mode is active.
Always On Lateral (Independent)
Always On Lateral keeps steering active even when cruise control is off. It has absolutely no connection to the Chill Mode vs. Experimental Mode distinction. These features control completely different systems: Always On Lateral manages steering persistence, while modes manage gas and braking logic. You can have Always On Lateral active in Chill Mode, Experimental Mode, or while switching between them. The steering behavior doesn't change.
Curve Speed Controller (Works in Chill Mode)
Curve Speed Controller reduces your target speed for upcoming curves. Like Speed Limit Controller, it works by adjusting the cruise speed that Chill Mode's Adaptive Cruise Control targets. The curve slowdown happens regardless of whether you're in Chill Mode or Experimental Mode. You don't need Experimental Mode for your car to slow for curves.
Custom Driving Personalities (Apply in Chill Mode)
Your chosen driving personality (Traffic, Aggressive, Standard, or Relaxed) adjusts the following distance and acceleration smoothness that Chill Mode's Adaptive Cruise Control uses. These are the direct tuning knobs for how Chill Mode feels while driving. Switching to a closer following distance (Aggressive or Traffic) makes Chill Mode more responsive in traffic, while Relaxed gives more buffer space.
Speed Limit Controller (Works in Chill Mode)
Speed Limit Controller adjusts your target speed based on posted speed limits. It works in Chill Mode by modifying the cruise speed that the Adaptive Cruise Control logic targets. This means your car will automatically match speed limits even in Chill Mode's straightforward cruise control mode. If Speed Limit Controller can't find a speed limit and its fallback is set to "Experimental Mode," it will trigger a switch out of Chill Mode through Conditional Experimental Mode (status code 13).
Traffic Mode (Works in Both Modes)
Traffic Mode is a specialized driving personality designed for stop-and-go congestion. It works within Chill Mode by tightening following distances and adjusting acceleration rates. One notable interaction: when Traffic Mode is active, Conditional Experimental Mode's stop light detection is suppressed, keeping the system in Chill Mode even when the driving model predicts a stop. This is because Traffic Mode's close-following behavior handles congestion situations without needing the AI model's interpretation.
Limitations & Known Behaviors
Chill Mode is a driving state, not a configurable feature. Here's what that means in practice.
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Chill Mode has no settings of its own. You can't adjust Chill Mode directly. Instead, you adjust the features that operate within it: driving personalities for following behavior, Speed Limit Controller for speed matching, and Curve Speed Controller for curve handling. Chill Mode is simply the result of Experimental Mode being off.
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Chill Mode will not brake for traffic lights or stop signs. This is by design, not a bug. In Chill Mode, the system maintains your set speed and follows the car ahead. It doesn't interpret visual cues from the camera to make braking decisions. If you need the system to attempt stopping for traffic signals, you need Experimental Mode active (either manually or through Conditional Experimental Mode).
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The Chill Mode vs. Experimental Mode distinction only exists when openpilot controls gas and brakes. If your car uses its factory cruise control for speed (stock longitudinal), there's effectively only one mode: whatever your car's built-in system provides. The Experimental Mode toggle will be grayed out (disabled) in settings, and Conditional Experimental Mode won't be available. On these cars, openpilot handles steering only.
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You can't be in both modes simultaneously. Chill Mode and Experimental Mode are mutually exclusive states. The longitudinal planner runs in either Adaptive Cruise Control mode (Chill) or blended mode (Experimental), never both.
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Chill Mode is not the same as being disengaged. When openpilot is disengaged, it isn't controlling anything. In Chill Mode, openpilot is actively controlling your gas and brakes, just using conventional cruise control logic rather than AI-driven decisions.
Q: My car isn't braking for red lights. Is something wrong?
A: No, this is expected Chill Mode behavior. Chill Mode uses conventional cruise control logic that doesn't interpret traffic lights. If you want the system to attempt braking for traffic signals, you need Experimental Mode active. The easiest way is to enable Conditional Experimental Mode (on by default) and set a speed threshold under Below (No Lead) in its settings. The system will then automatically switch to Experimental Mode when you're driving at lower speeds in areas with traffic lights.
Q: My car keeps switching out of Chill Mode unexpectedly. How do I stop it?
A: Conditional Experimental Mode is switching your car to Experimental Mode because one of its trigger conditions is being met. Look at the status widget on your driving screen. The icon tells you exactly what's triggering the switch. Common causes include: your speed dropping below the configured speed threshold, curve detection triggering on gentle highway bends, or navigation detecting an upcoming intersection. You can either disable the specific trigger that's causing it, or lower the relevant speed thresholds so they don't activate at highway speeds.
Q: I want to always stay in Chill Mode. How do I lock it in?
A: You have two options. The simplest is to disable Conditional Experimental Mode entirely (find it under FrogPilot → Driving Controls → Gas / Brake → Conditional Experimental Mode) and then turn off Experimental Mode in the Toggles panel. Without Conditional Experimental Mode and with Experimental Mode off, your car will always stay in Chill Mode.
Q: The status widget shows the Chill Mode icon but with a yellow border. What does that mean?
A: A yellow border means you manually overrode Conditional Experimental Mode to force Chill Mode. At some point, you tapped the steering wheel icon on screen while the system was in Experimental Mode, which forced a switch to Chill Mode and paused automatic switching. Tap the steering wheel icon again to clear the override and return to automatic control.
Q: The Chill Mode option doesn't seem to exist anywhere in my settings. Where is it?
A: Chill Mode isn't a toggle you enable or disable. It's the state your car is in whenever Experimental Mode is not active. If you can see the Experimental Mode toggle in your Toggles panel and it's turned off, you're in Chill Mode. If the Experimental Mode toggle is grayed out, your car likely doesn't support openpilot gas and brake control, which means the mode distinction doesn't apply to your setup.
Q: What's the difference between Chill Mode and the Standard driving personality?
A: These are two different things that work together. Chill Mode vs. Experimental Mode determines how speed decisions are made (conventional cruise control vs. AI-driven model). The driving personality (Traffic, Aggressive, Standard, Relaxed) determines the style of those decisions, like following distance and acceleration smoothness. You can be in Chill Mode with an Aggressive personality (close following, quick acceleration) or Chill Mode with a Relaxed personality (larger gap, gentler speed changes). The personality adjusts the behavior within whichever mode is active.
Q: Does Chill Mode still use my car's radar for following the car ahead?
A: Yes. In Chill Mode, the system uses radar data (if your car has it) to track the vehicle ahead and maintain a safe following distance. This is the same proven Adaptive Cruise Control logic used by standard openpilot. Experimental Mode adds camera-based model predictions on top of this, but Chill Mode relies on the conventional radar-based following.
Q: I have Curve Speed Controller enabled. Does it only work in Experimental Mode?
A: No. Curve Speed Controller works in both Chill Mode and Experimental Mode. It operates by adjusting your target cruise speed based on detected road curvature. In Chill Mode, the reduced target speed is fed directly into the Adaptive Cruise Control logic, causing your car to slow for curves without needing AI-driven braking decisions.
Q: My car is a Toyota with stock cruise control. Do I have Chill Mode?
A: If your car uses its own factory cruise control for gas and braking (stock longitudinal), the distinction between Chill Mode and Experimental Mode doesn't apply. openpilot is only handling steering on your car. Your car's built-in cruise control manages speed in its own way. To unlock the Chill Mode / Experimental Mode distinction, your car needs to support openpilot gas and brake control, which may require specific hardware (like a comma pedal or Smart Driver Support Unit on some Toyotas).
Q: I see "CHILL MODE ON" on my screen. What does that button do?
A: That button appears on the right side of the home screen (the main offroad screen you see when the car is parked). It shows your current driving mode. "CHILL MODE ON" means Experimental Mode is turned off. Tapping the button navigates to the Toggles settings panel and expands the Experimental Mode toggle where you can switch modes. Note that if Conditional Experimental Mode is enabled, manual mode changes through this toggle may be overridden by automatic switching once you start driving.
Related Features
Chill Mode is the baseline state that these features either switch away from, complement, or work within.
| Feature | Relationship | How it interacts |
|---|---|---|
| Conditional Experimental Mode | Manages transitions | Automatically switches between Chill Mode and Experimental Mode based on driving conditions. Chill Mode is the default state that the system returns to when no trigger conditions are met. |
| Curve Speed Controller | Works within | Reduces your target speed for curves regardless of driving mode. In Chill Mode, the adjusted speed is handled by conventional Adaptive Cruise Control logic. |
| Experimental Mode | Opposite state | The AI-driven alternative to Chill Mode. When Experimental Mode activates, Chill Mode deactivates, and vice versa. |
| Speed Limit Controller | Works within / can trigger exit | Adjusts your cruise speed based on posted limits in Chill Mode. Can also trigger a switch to Experimental Mode when no speed limit is found and its fallback is configured for it. |
