Instrument cluster with several driver assist warnings lit at once

Honda Sensing Fault: Why ACC, Lane Assist and Collision Warnings Often Come On Together

Honda Sensing warning on your Civic, CR-V or HR-V, with ACC, Lane Keeping Assist (LKAS) and Collision Mitigation messages often arriving together? Honda Sensing reads the road through a forward camera behind the windscreen, Honda calls it the multipurpose camera unit, and a millimetre-wave radar behind the front grille. ACC leans on the radar, LKAS on the camera, and the Collision Mitigation Braking System (CMBS) reads both, so one disturbed sensor can fill the dash. The checks that cost nothing come first; calibration, when your car needs one, is from £162 inc VAT.

Please note

Safe to drive, but the assists are off

You can drive the car. With a Sensing fault showing, the Collision Mitigation Braking System isn't watching the road for you, and whatever shares the faulted sensor usually drops with it: Adaptive Cruise Control when it's the front radar, Lane Keeping Assist and Road Departure Mitigation when it's the windscreen camera. Normal brakes and steering are untouched. Leave more following distance and don't lean on the assists until it's sorted.

What's actually triggering Honda Sensing on your car

Honda Sensing reads the road through two sensors: the multipurpose camera unit at the top of the windscreen and a millimetre-wave radar behind the front grille. ACC leans on the radar, LKAS on the camera, and CMBS reads both, which is why one lost aim can put three or four warnings up at once. The triggers, most common first.

Adaptive Cruise Control leans on the radar. Lane Keeping Assist and Road Departure Mitigation read the camera. The Collision Mitigation Braking System reads both. So a radar that's lost its aim flags ACC and CMBS together, a camera that's lost its aim flags LKAS and CMBS, and to the driver it looks like the whole suite failing at once. It's still one root cause, one sensor, and usually one calibration to clear it.

The big camera-side trigger, and the usual story behind the Civic's 'out of automatic correction range' message. The multipurpose camera unit comes off with the old glass and goes back on with the new, and its aim shifts by more than the small drift Honda Sensing can absorb on its own. Past that range the car stops trusting the image and stays flagged. The calibration is a separate step that many windscreen fitters don't carry kit for, which is why the warnings often show up on the drive home. The fix is a static aim against the target board, run to Honda's documented calibration procedure: front camera calibration, £162 inc VAT (£135 +VAT) at a centre.

The millimetre-wave radar sits behind the front grille, right where the work happens. Unclipping and refitting a bumper, a new grille, or a front-end repair can shift its aim by enough to stop the aiming routine completing, which is what the CR-V's 'Millimeter Wave Radar Aiming Incomplete' message with fault code B2A60-54 is reporting. ACC and CMBS read from the radar, so those warnings tend to land first. After a bigger front-end job the camera can have moved too; both are checked, and calibrated where needed, in the same visit.

The camera aims through the windscreen, so the glass in front of the lens is part of the optical path. On the HR-V, aftermarket glass is one of the typical triggers we see, and it's the first thing to check when a calibration keeps failing to hold after a screen swap. Tell the centre what glass went on when you enquire, and the written quote takes it into account.

Trolley contact in a car park, a kerb strike on the lower bumper trim, a nudge that never left a mark. None of them show visible damage, but any of them can shift the radar bracket behind the grille enough to throw a warning days later. A slow walk round the front end costs nothing and is worth doing before anything is booked.

Every sensor Honda Sensing uses for CMBS, ACC and LKAS sits at the front of the car, so a rear bumper coming off for a repaint doesn't touch them and shouldn't put a Sensing warning on the dash. What a rear bumper job can disturb is the rear parking sensors, which unclip with the bumper skin. If a parking fault appears after the refit, that's a set-up job on the parking module rather than a Sensing calibration, priced as its own line: £184.80 inc VAT (£154 +VAT) at a centre.

If the trigger was a real impact rather than a minor knock, the radar housing or the camera bracket can be cracked rather than just shifted, and a calibration won't hold on damaged hardware. This is what the diagnostic scan is for: it says which case you're in before any work is booked, and if a camera or radar does need replacing, the rate card has a line for the coding and calibration that follow.

How we fix it

Worth checking first: note which warnings arrived together, because the pattern points at the sensor. ACC flagging alongside CMBS leans towards the front radar; LKAS or Road Departure Mitigation in the mix points at the windscreen camera. Then the free checks: was the windscreen recently replaced, and what glass went on? Walk round the front end for signs of bumper or grille work, or a parking knock. Honda Sensing absorbs small aim drift on its own, so a one-off warning that goes and stays gone needs nothing booked. One that keeps returning, or arrived with glass or bodywork, is past the correction range, and the car keeps flagging until the aim is reset.

Still showing? The job starts with a diagnostic scan, £54 inc VAT (£45 +VAT), always itemised as its own line. A Sensing fault has more than one possible ending, a camera moved by a glass swap, a radar shifted by bumper work, or hardware that's genuinely damaged, and the scan settles which one yours is before anything is booked.

From there it's one of three jobs:

  1. The camera's lost its aim. The usual outcome after a windscreen swap. It's a static aim against a target board whose references are set per model and Sensing generation, run to Honda's documented calibration procedure: front camera calibration, £162 inc VAT (£135 +VAT) at a centre.
  2. The radar's lost its aim. The normal outcome after bumper or grille work. It's the radar aiming routine against a separate radar target, and calibration runs to full manufacturer specification. Front radar calibration is £162 inc VAT (£135 +VAT); where both sensors moved, both are done in the same visit. Two or more systems in one visit: the highest-priced system is full price and each additional system is 35% off at a centre.
  3. A sensor was replaced. A new camera or radar needs coding to your car as well as the aim, and the rate card carries them as two lines: the coding for the new part, then the calibration for that system, discounted as an additional system in the same visit. Front radar replaced: £232.80 inc VAT (£194 +VAT) codes the new module, and the front radar calibration is a separate line on top at the second-system discount. The camera line below pairs the same way. Front camera replaced: £229.20 inc VAT (£191 +VAT).

Every job closes with the paperwork. Certificate to manufacturer tolerances, the same standard dealers issue. Your quote is confirmed in writing before anything is booked. The procedure itself, step by step, is in our ADAS calibration guide.

Honda calibration prices

One system is the usual quote here: the windscreen camera after a glass swap, or the front radar after bumper or grille work. Rates are the same at every service centre, per system, shown inc VAT with the net figure alongside. Your total is confirmed in writing before anything is booked.

Calibration — per system

Service At a service centre
Front camera calibration £162 inc VAT (£135 +VAT)
Front radar calibration £162 inc VAT (£135 +VAT)
Blind spot radar calibration £162 inc VAT (£135 +VAT)
360° / surround camera calibration £162 inc VAT (£135 +VAT)
Reversing camera calibration £206.40 inc VAT (£172 +VAT)
Parking sensor calibration £184.80 inc VAT (£154 +VAT)

Coding a replaced part to your vehicle

Service At a service centre
Front radar replaced £232.80 inc VAT (£194 +VAT)
Front camera replaced £229.20 inc VAT (£191 +VAT)
Blind spot radar replaced £226.80 inc VAT (£189 +VAT)
Reversing camera replaced £213.60 inc VAT (£178 +VAT)
  • When your job needs a diagnostic pre-scan, it's £54 inc VAT (£45 +VAT), itemised separately. It reads available fault information; finding the cause may require further investigation. A post-scan is a separate operation.
  • Two or more systems in one visit: the highest-priced system is full price, each additional system is 35% off at a centre. Scans aren't part of the discount. Front camera and front radar together come to £267.30 inc VAT (£222.75 +VAT).
  • Replacement configuration and calibration are different operations. The work required depends on the vehicle and what the installer has already completed. Configuration prices do not include supplying or fitting a replacement part, or an automatic calibration bundle.
  • Unsuccessful work, further investigation or a return visit may carry charges, including at a service centre. The appointment terms and written quote set out the work and applicable charges before booking.
  • Mobile calibration is available for garages and bodyshops with workshop conditions. Ask us.

Get your Honda's Sensing calibration booked

Send your registration and a line on what's happened. We come back with the itemised quote, the nearest of 80+ UK service centres, and the soonest slot.

  • Per-system pricing, from £162 inc VAT.
  • Your quote is confirmed in writing before anything is booked.
  • Certificate to manufacturer tolerances, the same standard dealers issue.
STEP 1 / 3 ~60 sec

Tell us about your car

A few details

Photos (optional)

How do we reach you?

Helps us match you to your nearest centre and verify it's you when we call.

We'll call you from 01246 223132 (our booking line) within 3 hours, Mon–Fri 8am–5pm. Save the number so you know it's us.

Frequently asked questions

Almost always one. Honda Sensing runs its features through a shared sensor pair: Adaptive Cruise Control leans on the millimetre-wave radar behind the front grille, Lane Keeping Assist on the multipurpose camera unit behind the windscreen, and the Collision Mitigation Braking System reads both. When one sensor loses its aim, every feature that reads from it flags at the same moment. It looks like several faults but it's one cause, and one calibration usually clears the lot: front camera calibration is £162 inc VAT (£135 +VAT) in a centre visit.

It's priced per system, and which system depends on what set the warnings off: usually the windscreen camera after a glass swap, the trigger on most of the Hondas we see, or the front radar after bumper or grille work. Front camera calibration is £162 inc VAT (£135 +VAT), front radar is the same, with the full rate card on this page. Two or more systems in one visit: the highest-priced system is full price and each additional system is 35% off at a centre. A diagnostic scan, when your job needs one, is priced and itemised separately. Your quote is confirmed in writing before anything is booked.

The camera aims through the windscreen, so the glass in front of the lens is part of the optical path, and glass quality in the camera zone can be the difference between an aim that holds and one that doesn't; on the HR-V, aftermarket glass is one of the typical triggers behind Sensing calibrations that won't settle. Say the screen is aftermarket when you enquire. The centre runs the static aim to Honda's documented procedure and confirms in writing what it found, so if the glass itself is the blocker you know before paying for repeat attempts. Whether a different screen then goes on is between you and your insurer. The calibration is one line either way: front camera calibration, £162 inc VAT (£135 +VAT) at a centre.

No. The job needs a calibration bay, the aim references for your model's Sensing generation, and Honda's documented calibration procedure, and our service centres run all three; none of it is franchise-only. Provided the work runs to Honda's specification, an independent calibration doesn't invalidate your warranty under UK block exemption rules. Certificate to manufacturer tolerances, the same standard dealers issue. Dealer quotes for ADAS work run £300 to £900 in quotes customers have shown us.

Sometimes, and Honda designed it that way: the system absorbs small amounts of aim drift automatically, so a one-off warning that goes and stays gone needs nothing booked. The Civic's 'out of automatic correction range' message is the other case: the camera's aim has moved further than the car can correct itself, usually after a windscreen swap or front-end work, and it stays flagged however far you drive. The same goes for the CR-V's radar aiming message after bumper work. A warning that keeps returning is a lost aim, not a glitch, and a calibration is the fix: front camera or front radar, each £162 inc VAT (£135 +VAT) per system at a centre.

Usually the coding and the aim. A replacement camera or radar has to be coded to your car and then calibrated before the Sensing self-checks trust it, and fitting the part does neither on its own, which is why a brand-new unit can arrive fitted and still show the fault. The rate card prices the coding on its own: front radar module following replacement costs £232.80 inc VAT (£194 +VAT), front camera module following replacement is £229.20 inc VAT (£191 +VAT), and the calibration for that sensor is then a separate line, discounted as the second system in the visit. Say whether the unit was new or second-hand when you enquire: a used module can be attempted, coding one isn't always possible, and the centre confirms the scope in writing before anything is booked.

Related ADAS warning guides

Most Sensing faults start with one of two repairs, and each has its own cross-make guide. If yours began with glass or bodywork, the detail lives there.

Book your Honda's ADAS calibration

Send your registration and what's been done. We come back with the price, the nearest service centre, and the soonest slot.

Get a Free Quote