Dashboard

The gauge grid

When the session is Ready, tiles update from the ECU. Tap Edit to add and remove gauges, drag tiles, pull a corner to resize, and tap a tile to set its style, range, redline and colour. Tap Done when it looks like a dash you can read at a glance.

PIDs opens the picker. Search by name. Imported sensors from a CSV show up here too, once they have been probed. See Custom PIDs.

Each vehicle profile keeps its own layout. Switching profile switches the dash, the adapter, and the protocol hint together.

What the numbers are

Mode 01

Generic OBD-II. RPM, speed, coolant, throttle, engine load, battery voltage (ATRV, with a PID fallback), oxygen sensors, fuel trims, MAP, MAF, whatever this ECU actually answers. Unsupported PIDs stay off the picker rather than sitting at zero pretending.

VAG Mode 22

On Volkswagen, Audi, SEAT and Škoda, RevDash also probes a built-in Mode 22 set: oil temperature, charge pressure actual and specified, torque actual and requested, lambda, timing, rail pressure, wastegate, and current gear from the TCM when a DSG answers. Only DIDs the ECU replies to appear as supported.

Derived values

These are arithmetic over PIDs the car already reports, not extra sensors:

• Gear (estimated): RPM and speed, so it works on a manual. Flickers or drops to 0 during a shift; first gear is the weak spot.
• Boost: from MAP, once atmospheric pressure is known.
• Fuel flow, consumption, CO₂: need a fuel type on the profile, plus MAF or a fuel-rate PID. They stay blank on an EV, on purpose.

Charts

Charts on the dash. A rolling window of the parameters you care about. The window length is in Settings: 15s, 30s, 1m, 2m or 5m. From Edit you can open a single gauge’s trace as well.

Poll pace (Fast / Normal / Eco) is also in Settings. The adapter reads one PID at a time; Fast drops the extra wait, but more gauges still share the bus.

HUD

HUD takes the first four gauges on the dash, draws them very large in amber on black, and mirrors them so a windscreen reflection reads the right way round. Mirroring is on by default; the switch in the HUD chrome turns it off if you are using it as big-numbers mode rather than a reflection. The screen stays on at full brightness while HUD is open, then restores whatever you had.

More than four gauges would not be readable at a glance, and picking a separate HUD set would be another editor. Dash order is already your priority, put the four you want while driving at the front of the layout.

Alarms

Settings → Alarms. One threshold per PID, above or below, spoken or silent. The PID does not have to be on the dash; an alarm adds it to the poll plan so a warning you cannot see still fires.

• Thresholds are stored in metric. The number you type is converted; flipping units later will not turn 100 °C into 100 °F.
• Crossing announces once, then repeats every 60 seconds while it stays crossed.
• Hysteresis is 2% of the threshold, minimum one unit, so a needle on the line does not chatter.
• If the phone has no speech engine, the banner still fires and Settings says speech is unavailable. It will not fail silently.

Alarms follow the driver, not the vehicle: they persist in the backup zip as alarms/alarms.revalarm.

Fault codes

Codes on the dash, with the adapter connected. Stored, pending and permanent banks, freeze frame, and generic SAE titles. Clearing asks before it does anything. Permanent codes cannot be cleared from a scan tool; they go when the ECU is satisfied.

These are generic definitions. Confirm against a manufacturer procedure before repair work. Powertrain only, generic OBD-II does not expose ABS or airbags.

Timed runs

Perf on the dash. Stop the car, tap Get ready, then go. RevDash times, from a standing start:

• 0–60 mph
• 0–100 km/h
• 1/8 mile
• 1/4 mile (with trap speed)

Times come from the car’s own speed sensor over the adapter. They are good for comparing your runs with each other, and not for settling arguments. Speedometers read high by a few percent by design, and a slow adapter is called out as a coarse result rather than a confident hundredth. The screen also keeps trip totals (distance, duration, fuel if it can be measured) with a reset of their own.

Appearance

Settings → Theme: Night, Day, OLED, Midnight. Keep-screen-on is the other switch that matters in a mount. None of this leaves the phone.