Vauxhall Astra Warning Lights: Every Dashboard Symbol, and Why an Astra L Answers Differently to an Astra H

The Astra changed hands, and the dashboard changed with it

Colour is the one part of an Astra dashboard that has never changed. Red means stop as soon as you safely can, amber means a fault has been stored, and green, blue or white only confirm that something is switched on — our guide to what a dashboard warning light is actually telling you sets that out in full.

Everything behind the colour has changed. The Astra G, H and J were General Motors cars with GM electrical architecture, and the K was the last of that line. The Astra L is a Stellantis car built on the EMP2 platform, and its control units and driver-information messages come from the PSA lineage rather than the GM one. Under the skin it has more in common with a Peugeot 308 than with the Astra J it replaced two generations later.

That is not a detail for enthusiasts. It decides whether a fault pattern applies to your car at all. The two best-known Astra electrical faults — the brake-pressure sensor sealed inside the ABS unit, and the Easytronic clutch actuator — belong to the GM cars and do not exist on an L. Meanwhile almost everything published about Astra warning lights was written about the H, which is now the oldest generation most people are still driving.

The first-registration date on the V5C settles the year, and the dashboard settles the rest — two analogue dials with a small trip display on the G and H, a colour screen in the middle of the cluster on many K-generation cars, and a wide digital panel available only on the L. The dates overlap slightly at each changeover, so where the year is ambiguous, trust the dashboard.

Vauxhall Astra warning lights and symbols: the full reference table

This is filtered to lamps an Astra carries. The marque-wide Vauxhall symbol set covers the whole range, including all-wheel-drive descent control, air suspension and van-specific warnings, and none of those belong on a hatchback — when you are matching a shape you can see against a list you cannot, that padding gets in the way. The safe-to-drive column assumes the serious reading wherever a fault could reasonably be trivial or serious.

Colour	Symbol	What it means on an Astra	Is it safe to drive?
Red	Brake system — an exclamation mark in a circle with a bracket each side	The handbrake is still applied, or fluid has fallen below minimum. On a manual Astra this lamp covers the clutch fluid too, because the two share a reservoir.	No, unless it goes out the moment the handbrake is fully released. If it stays lit, stop somewhere safe and arrange recovery.
Red	Brake system and ABS lit together	Both braking systems reporting at once. The same unit distributes braking effort front to rear, so that balance may no longer be there.	No. Brake gently, stop as soon as it is safe, and have the car recovered rather than driven on.
Red	Engine oil pressure — an oil can with a drip	Oil pressure has fallen. This is the pressure lamp, not the amber low-level warning further down.	No. Switch the engine off. Bearings are damaged in seconds without oil pressure, not in miles.
Red	Coolant temperature — a thermometer in wavy lines, sometimes with a stop-engine warning	The engine is overheating: coolant low, coolant not circulating, or a failed thermostat, water pump or fan.	No. Stop, switch off and let it cool. Never open a hot expansion tank.
Red	Charging system — a battery with plus and minus terminals	The battery is no longer being replenished. Alternator, drive belt, a connection or the wiring.	Only as far as somewhere safe. Everything is running on stored charge, and the car stops when it is gone.
Red	Airbag and belt tensioners — a seated figure facing an inflated circle	The restraint system has stored a fault. An airbag or a seatbelt pretensioner may not fire in a collision.	The car drives normally, but the protection you are relying on is not there. Have it read straight away.
Red	Engine or transmission electronics — a car outline with a spanner through it	Vauxhall’s powertrain and electronics fault lamp. It is not a service reminder, and the plain spanner further down is a different symbol entirely.	Short journeys at most, and only while the car drives normally. Have the codes read rather than booking a service.
Red	Power steering fault — a steering wheel with an exclamation mark	Steering assistance has failed or been cut.	No. Assistance can disappear without notice, and the steering goes heavy at exactly the moment you need it.
Red or amber	Immobiliser, and Open & Start where fitted — a car outline with a key	Flashing yellow means the key was not recognised and the engine will not start. Steady red is a stored immobiliser fault. On Open & Start cars it can also mean the steering lock has not released.	If it has started, yes for now. If it cranks and dies, or will not crank, it is going nowhere until the codes are read.
Red	Seat belt, and a door, bonnet or tailgate ajar	A belt is unfastened, or a closure is not properly latched.	Stop and put it right before driving on. Neither is a fault in the car.
Amber	Engine management, and emission control — an engine block, and an exhaust with wisps of smoke	Steady: a stored powertrain fault, or emission limits exceeded. Flashing: a fault that can damage the catalytic converter, usually an active misfire.	Steady and driving normally: gently, and get the codes read within days. Flashing: stop. A management lamp that stays lit also fails the MOT.
Amber	ABS — the letters ABS in a circle with a bracket each side	The anti-lock function has switched itself off. Ordinary braking is unaffected.	With care, provided the red brake lamp is not lit as well. The wheels can lock in an emergency stop, so leave more room and brake earlier. It is also an MOT defect.
Amber	Stability and traction control, and the OFF version	Flashing means the system is intervening and working. Steady means it is switched off or has a fault. Not fitted to every Astra G.	Flashing on a wet or greasy road is normal. Steady on dry tarmac in ordinary driving means it is not protecting you — and see the ESP section below before assuming it is the button.
Amber	Power steering, reduced or needing calibration — an amber steering wheel	Vauxhall’s symbol set splits this three ways: assistance disabled, assistance reduced because the unit has overheated, and a system that needs calibrating.	The first is a stop-and-check. The other two are drive-with-care and get it read, because reduced assistance can become none without warning.
Amber	Diesel particulate filter — a filter box with dots inside	Steady: the filter is full of soot and wants a regeneration. Flashing: it has reached its maximum level, and the Astra will start limiting itself — first to 60mph from the next restart, then further, up to refusing to restart at all.	Steady, yes — a sustained run at a steady speed with the exhaust properly hot often completes a regeneration. Flashing needs attention now, before the car limits itself.
Amber	Diesel Astras only — a coiled filament, and a filter box with a water droplet	The preheat coil is normal for a few seconds before a cold start; lit or flashing while driving it is a stored engine fault instead. The droplet means water has collected in the fuel filter.	Preheat: yes, but have it read if it stays on. Water in fuel: only briefly, because water reaching the injection system does expensive damage.
Amber	Low levels — an oil can with a level line, and an expansion tank with a level line	Engine oil or coolant is below minimum. Neither is the red pressure or temperature lamp, and the two pairs get confused constantly.	Yes, briefly. Check with the engine cold and top up. A level that drops again quickly is a leak, not a habit.
Amber	Service due, or oil change due — a plain spanner	A time or mileage interval has been reached, and it is reset at the service. Vauxhall also words this as a service-vehicle-soon message on cars with a display.	Yes. This is the reminder. The car-with-a-spanner-through-it above is the fault.
Amber	Brake pads worn — a circle drawn as a broken dashed ring	The wear sensor has reached the pads’ limit.	Yes, but book it now. The warning arrives with a margin left, and that margin is finite.
Amber	Tyre pressure — a horseshoe with an exclamation mark	A tyre is below pressure, or the monitoring system itself has a fault. On the Astra H this is the deflation detection system, which shows red for pressure loss and yellow for a fault in the system.	Only as far as somewhere you can check all four pressures. Reduce speed and avoid hard braking until you have.
Amber	Bulb replacement, and headlight faults — a bulb with a break, and a headlamp with an exclamation mark	An exterior lamp is out, or the circuit driving it has failed. On cars with adaptive forward lighting the second symbol reports a levelling or bending fault, and the lights may drop to a symmetrical low beam.	Yes, but a lamp that is out is an MOT failure and a hazard after dark. A warning that persists after a new bulb is pointing at the circuit, not the bulb.
Amber	Stop-start fault — the letter A inside a circular arrow	The system has taken itself out of use, most often because the battery is no longer holding enough charge for it.	Yes. The engine simply stops shutting down at junctions. Have the battery and its current sensor checked first.
Amber	Reduced engine power, automatic transmission warning, and Easytronic transmission electronics — no shared glyph; read the display	Reduced power means the engine has dropped into a protective limp mode. The transmission warnings are a gearbox or clutch-control fault, and on an Easytronic the giveaway is an F or an N in the gear display, solid or flashing.	Limited. Limp mode holds low power and sometimes a single gear, so keep the journey short and off fast roads. An Easytronic showing F may not select a gear at all.
Amber	Generic warning, consult workshop — an exclamation mark in a triangle	Vauxhall’s catch-all. The symbol carries no information on its own; on cars with a display, the text beside it is the actual warning.	Read the message first and treat it as whatever it names. Amber means get it looked at, not ignore it.
Amber	Driver assistance — a car between lane lines, plus following distance, parking assist and hill start assist	Lane departure, following-distance or parking assistance is unavailable or intervening. Usually the camera or the sensors cannot see: dirt, ice, snow or road film. On Astra H cars with interactive driving and continuous damping control, a fault in those systems reports here too.	Yes. The car drives normally and the assistance is simply not there, so do not rely on it until the lamp goes out.
Green, blue and amber tell-tales	Dipped beam, main beam, indicators, front and rear fog lights, low fuel, passenger airbag switched off	These confirm that something is switched on, or that a level is low. Indications rather than faults. Vauxhall adds an upshift prompt and an icy-road warning to the same family.	Yes. Two are worth a second look: a rear fog light dazzles the car behind, and a passenger airbag shown as off should be off deliberately.

Five Astra lamps that generic guides read wrong

These are the five where following advice written for cars in general, rather than for this car, sends people to the wrong part.

The car with a spanner through it is not a service reminder. Vauxhall uses two separate spanner symbols, and they mean opposite things. A plain spanner is the service or oil-change reminder, reset when the work is done. A small car outline with a spanner through it is the engine and transmission electronics warning — a stored powertrain or control-unit fault. Book a service for the second one and you will collect the car with the lamp still lit, having spent the interval on the wrong thing.

The red brake lamp also covers the clutch on a manual Astra. Generic guides give you the handbrake and the brake fluid and stop there. Vauxhall’s own wording pairs the parking brake with the clutch fluid level, because the clutch hydraulics draw from the same reservoir on a manual car. So a red brake lamp with a clutch that has gone long or spongy is not two problems — it is one, and the level is the first thing to look at.

"Top up the power steering fluid" is the wrong instruction for most Astras. Vauxhall’s symbol set splits the amber steering warning three ways: assistance disabled, assistance reduced because the unit has overheated, and a system that needs calibrating. A system that can overheat and can need calibrating is an electrically assisted one, and there is no reservoir behind it to fill. Open the bonnet and look for a power steering fluid reservoir before you take that advice: if there is not one, the lamp is reporting electronics, and no amount of topping up will change it.

An ESP lamp that will not clear with the button is a specific fault, not a stuck switch. Across the post-2004 Vauxhall and Opel range — Astra, Corsa, Zafira, Meriva and Vectra — there is a well-documented pattern where the stability lamp stays on, the ESP OFF or traction button does nothing at all, and the ABS lamp often joins in. The cause is a brake-pressure sensor failure inside the ABS unit, logged as G201 or 01435. If pressing the button changes nothing, stop treating it as a switch.

An F or an N in the gear display is a warning, not a gear. On an Astra with the Easytronic automated manual, the display sits where the gear number should be and shows F or N, solid or flashing, when the transmission electronics have a fault. Flashing tends to arrive with a car that will not select a gear or will not start. It is easy to read as a quirk of the display because it does not look like a warning symbol, and it is the clearest signal this gearbox gives.

Which unit has actually failed: the Astra lamps that sit in front of a module

Most lamps on an Astra are a sensor, a fluid, a bulb or an interval, and working through those first is the right order. A handful are different: they sit in front of a control unit, and checking levels will never move them. The units below are a narrow slice of the units we repair, picked because on this car they are the ones that announce themselves with a lamp rather than a noise or a leak.

ABS and ESP

Anti-lock braking and stability control share a hydraulic modulator and a control unit, which is why a fault in one so often lights both. On the Astra the recurring codes are pump motor circuit and pump motor faults, C0110 and C0200, and a brake pressure sensor fault, C1100 — and the separate ESP pattern above logs G201 or 01435. Wheel-speed sensors are a genuine and much cheaper cause, so the codes are what tell you which you are dealing with. Our background pages cover how an ABS pump actually works, what ESP does on a car, what does and does not clear an ABS light afterwards, and whether an ABS light fails the MOT. The repair work sits under ABS pump and module repairs, and the Corsa D ABS pump page shows what that work looks like on a Vauxhall unit of the same era.

The Easytronic clutch actuator

The Easytronic lets the control unit operate the clutch and select gears on what is mechanically a manual gearbox, and the actuator that does it is the same failing part across the Vauxhall range that used the system. The symptoms are consistent: F or N in the display, solid or flashing, gears that will not engage, and in the worst cases a car that will not start. One thing is worth knowing before you shop for a second-hand replacement — the actuator is coded to the vehicle, so a used unit from another car is rarely a straight swap. Vauxhall Easytronic clutch actuator repairs covers the fault, with the wider work under clutch and gear actuators and transmission control module repairs.

The instrument cluster

Rule the cluster in or out early, because one that is misreporting makes every other lamp on this page untrustworthy — you stop diagnosing the car and start diagnosing the thing describing the car to you. The signs are gauges that drop to zero, stick or sweep on their own, backlighting that flickers or fails, a screen that dims or comes and goes with temperature, missing segments, and several unrelated lamps lit with nothing behind them. That work sits under instrument cluster repairs, and repairing your own unit rather than fitting another keeps your mileage where it is.

Power steering

Where the assistance is electric, the steering lamp is reporting electronics and there is nothing to top up. Steering that is heavy from cold and normal once warm, assistance that fades in and out, or a wheel that goes heavy on one lock and not the other all point at the unit rather than the mechanical rack. Vauxhall’s overheating and calibration warnings are the tell that you are looking at an electrically assisted system. Those units are rebuilt under steering and EPS repairs.

The immobiliser, and Open & Start

If the immobiliser lamp flashes and the engine cranks strongly, fires for a moment and dies, the car has not authenticated the key and has blocked fuelling. Try the spare key first: it costs nothing and separates a failing key from a failing module in one attempt. On Astra H cars with Open & Start there is a second possibility — the steering lock not releasing — which presents as a car that will not crank at all. Our guide to a car that will not start, and whether it is the immobiliser takes it further. Where the symptoms are lighting, wipers, indicators or central locking rather than starting, that is the body control module instead.

Engine management, and where it goes

Too many possible causes to guess at, so the codes come first. If diagnosis points at an internal failure of the engine ECU itself, that work belongs with the independent specialists at ecu-repairs.com. If it points at the turbocharger — the management lamp often arrives alongside lost boost and a smoke complaint on the diesels — that is one for our turbo specialists at turbo-repairs.com, our sister site for everything turbo.

What to do when a warning light comes on in your Astra

1. Take the colour at face value. Red means find somewhere safe and stop. Amber means you have time to think about it, but not an unlimited amount of it.
2. Write down anything the display says, before you switch off. On a K or an L the written message carries more than the icon does, and some messages do not survive the ignition going off.
3. Establish which Astra you have. First-registration date on the V5C, then the dashboard. It decides whether a fault pattern you read about applies to your car at all.
4. Do the checks that cost nothing. Handbrake fully off, fuel cap clicked shut, oil and coolant levels with the engine cold, all four tyre pressures, closures latched, and a walk round for a dead bulb.
5. If a stability lamp is lit, press the ESP OFF button once. Not to switch anything off — to see whether it responds. A button that does nothing at all is information, and it points somewhere specific.
6. Have the codes read and recorded, and note which module reported them. That is half the diagnosis, and clearing the codes destroys it.

Two rules hold throughout: never attempt a do-it-yourself repair on the braking or restraint systems, and never clear a safety lamp simply to stop it bothering you. If you are working on a different car, the method is the same — we have built Vauxhall Corsa warning lights the same way, and Peugeot dashboard warning lights is the closer relative for an Astra L than anything else we have written.

Vauxhall Astra warning lights FAQs