Your Mercedes has come back from the body shop after a collision repair, the panel work looks perfect, but multiple ADAS warnings are showing on the dash. That's normal after a collision: DISTRONIC, Active Brake Assist, Blind Spot Assist, Pre-Safe and the multifunction camera typically all need clearing together. Here's what's involved and what the full reset costs.
You can drive the car, but you've lost the active safety net. The ADAS suite (DISTRONIC, Active Brake Assist, Blind Spot Assist, Pre-Safe, Lane Keeping) stays offline until the modules are recalibrated and the stored fault codes are cleared. Standard brakes, steering and conventional cruise still work. Leave more following distance and treat the assists as not there until it's sorted.
A collision repair on a modern Mercedes touches more ADAS hardware than most owners realise. The body shop returns the car to pre-accident condition mechanically; the ADAS step is separate and covers several sensors at once. Here's what we see needing attention.
Front-end collisions almost always disturb the DISTRONIC radar behind the three-pointed star. Even minor impacts can shift the aim, and a replacement bumper rarely puts the radar back to its exact original geometry. A static calibration restores it.
If the windscreen was replaced as part of the repair, or if the airbag deployment cracked it, the multifunction camera that backs up DISTRONIC needs recalibrating alongside the radar. Lane Keeping Assist and Traffic Sign Recognition flag from the same camera.
A rear-end or side collision affects the rear-quarter radars that run Blind Spot Assist. Even a front-end repair can disturb the rear radars if the body shop had to refit the rear bumper for paint matching. Both sides are calibrated in the same visit.
Pre-Safe (the pretensioner and pre-collision suite) doesn't directly need radar calibration, but it stores fault codes during a real impact event that have to be cleared by XENTRY before the system reactivates. Without this step the warning stays even after every sensor is back in tolerance.
After airbag deployment, the SRS module stores collision data that affects how the ADAS suite behaves on restart. Mercedes uses these stored values to decide whether Pre-Safe and Active Brake Assist can come back online. Clearing them is part of the full system reset.
If the multifunction camera was replaced as part of the repair (common on full windscreen-plus-camera replacement), the new camera needs VIN coding to the vehicle through XENTRY before calibration will hold. Fault codes specific to camera coding errors typically appear if this step is missed.
From around MY2018, the full procedure runs only through XENTRY at the right authorisation level. Aftermarket scan tools are locked out of several steps. Body shops without XENTRY access can complete the panels but can't do the ADAS reset themselves. Our network includes workshops with current XENTRY for the full post-collision reset.
Worth checking first: get a full list from the body shop of which panels were replaced, whether the windscreen was replaced, and whether airbags deployed. That tells the workshop which modules need attention and what target boards to prepare.
On a Mercedes that means a Full System Reset: pre-scan to record stored fault codes, front radar calibration with XENTRY, multifunction camera calibration if the windscreen was replaced, rear-quarter radar calibrations for Blind Spot Assist, Pre-Safe module reset, and a post-scan to confirm every module is clear. Front star removal and refit is part of the front radar step.
It's a fixed £499 through our network for the Full System Reset, covering everything together. The dealer route for the same procedure typically runs £1,200 to £1,800 because XENTRY time is billed per module separately. Same job, fixed network price. The full procedure is in our ADAS calibration guide.
Pricing is fixed across our network. Same price wherever you are in the UK. Your tier is set by what work has been done, not by your postcode or your car's make.
All prices include the diagnostic scan, the calibration procedure (static, dynamic, or both as required), a post-calibration check, and a calibration certificate. No charge for diagnostic if you decide not to proceed.
Send your registration and a line on what's happened. We'll come back with the fixed price, the nearest accredited workshop, and the soonest available slot.
Because ADAS calibration is a separate job from the bodywork. The body shop sorted the panels, paint and mechanical alignment, which is what makes the car safe to drive and structurally repaired.
What's left is the radar, camera and Pre-Safe module work that restores the safety systems to factory tolerance. Most body shops don't carry XENTRY-equipped calibration bays, so they hand the ADAS step back to you to arrange. That's the gap our accredited network fills.
The Full System Reset is a fixed £499 across our accredited network, the same wherever you are in the UK. That covers the front radar, the multifunction camera, both rear-quarter radars, Pre-Safe and SRS fault code clearing, and a post-scan with calibration certificate. The Mercedes dealer route for the same procedure typically runs £1,200 to £1,800.
Yes, almost always, when the calibration is part of an insurance claim. ADAS recalibration after collision repair is a recognised line item on UK motor claims, and insurers expect it on any ADAS-equipped Mercedes. The certificate we issue is the documentation that closes the claim file. If the body shop hadn't included calibration in the original estimate, raise it with the claims handler before paying anything yourself.
Typically a half-day. The Full System Reset runs through several modules in sequence, with target board changes between each, and a final post-scan. Plan to leave the car for the morning or afternoon. Your accredited workshop confirms the exact duration when you book based on which modules are involved.
The front radar calibration alone, if your repair was front-end only and the rear and SRS are unaffected.
The rear-quarter radar calibration alone, if your repair was rear-end only.