ADAS & Vehicle Technology

OEM Repair Procedures: Why They’re Non-Negotiable After a Collision

Every vehicle manufacturer — Honda, Toyota, GM, Ford, Subaru, BMW, and every other brand — publishes detailed repair procedures for their vehicles. These documents spell out exactly how a collision repair should be performed: which parts can be repaired and which must be replaced, what adhesives and fasteners to use, which welds are acceptable, what must be scanned, and what must be calibrated.

These are not suggestions. They are the manufacturer’s engineering specifications for returning a damaged vehicle to safe, pre-loss condition.

And yet, in collision repair shops across the country, OEM procedures are routinely ignored — sometimes because the shop does not look them up, and sometimes because the insurance company refuses to pay for them.

If your vehicle has been in a collision, understanding OEM repair procedures may be the most important thing you can do to protect your safety, your warranty, and your vehicle’s value.

What OEM Repair Procedures Actually Are

OEM stands for Original Equipment Manufacturer — the company that designed and built your vehicle. OEM repair procedures are the technical instructions that manufacturer publishes for repairing collision damage to their specific models.

These procedures cover a wide range of repair operations:

• Structural repair and sectioning — Where a structural member can be cut, what type of weld to use, what heat limits apply to high-strength steel and aluminum.
• Panel replacement — How to remove and install body panels, which attachment methods are approved, what seam sealers and corrosion protection to apply.
• Scanning requirements — When diagnostic scans must be performed before and after repairs. As we covered in our article on pre- and post-repair scanning, this step is critical for identifying hidden damage and verifying system integrity.
• ADAS calibration — Which sensors and cameras must be recalibrated after specific repairs, and what type of calibration is required. Our breakdown of static vs. dynamic calibration explains why this matters.
• Parts specifications — Whether a component must be replaced with new OEM parts, or whether repair or aftermarket substitution is acceptable.
• Restraint system procedures — How to handle airbag components, seat belt pretensioners, and other safety restraints after a collision.

These procedures are updated regularly as manufacturers learn more about their vehicles’ behavior in real-world collisions. A procedure that was acceptable two years ago may have been superseded by a revised instruction today.

Why Manufacturers Publish Them

Vehicle manufacturers publish repair procedures for one fundamental reason: they engineered the vehicle, and they know how it needs to be repaired to maintain its designed safety performance.

Modern vehicles are not simple assemblies of interchangeable steel panels. They are engineered systems where the body structure, the restraint system, the electrical architecture, and the advanced driver assistance systems all work together. A structural rail that absorbs crash energy in a specific way will not perform correctly if it is repaired with the wrong welding technique. An airbag system that deploys based on sensor data will not function properly if those sensors are not recalibrated after structural work.

As we discussed in our overview of ADAS and collision repair, today’s vehicles rely on interconnected networks of sensors, cameras, airbags, and crash-absorbing structures. Documentation of calibrations, scans, and inspections is not paperwork — it is evidence that the vehicle was returned to safe operating condition.

Manufacturers also publish these procedures to manage liability. If a vehicle is involved in a secondary collision and someone is injured, the question of whether the prior repair followed OEM procedures becomes central to determining fault.

What Major Manufacturers Have Said

Manufacturers do not leave their positions ambiguous. They publish formal position statements that make their expectations clear. Here is a sampling of what the industry’s largest brands have stated publicly:

Honda / Acura

Honda has published position statements requiring both pre-repair and post-repair diagnostic scans on all Honda and Acura vehicles involved in a collision. They have also published detailed ADAS calibration requirements, specifying which systems must be recalibrated after windshield replacement, structural repair, or suspension work. Honda explicitly states that failure to follow their procedures may compromise vehicle safety.

Toyota / Lexus

Toyota requires that all collision repairs follow Toyota Technical Information System (TIS) procedures. Their position statements address scanning, calibration, welding techniques for advanced high-strength steel, and structural repair limitations. Toyota has stated that repair facilities should access current procedures for every repair — not rely on general knowledge or past experience.

General Motors

GM publishes repair procedures through their Genuine GM Parts Collision website and has issued position statements on scanning, calibration, and structural repair. GM has been particularly clear about the requirement to scan vehicles before and after collision repairs, and about the need to recalibrate ADAS systems whenever components in the sensor path are removed, replaced, or disturbed.

Subaru

Subaru — whose EyeSight system is one of the most widely deployed ADAS platforms — has published extensive position statements on calibration requirements. EyeSight calibration is required after windshield replacement, camera removal, structural repairs, and wheel alignment changes. Subaru specifies that EyeSight calibration must be performed using Subaru-approved equipment.

Ford / Lincoln

Ford publishes repair procedures through their OEM repair network and has issued position statements addressing scanning, ADAS calibration, and structural repair. Ford has specifically addressed the need for post-repair scanning on all vehicles equipped with any electronic module — which, in current model years, means essentially every Ford and Lincoln on the road.

These are not obscure technical bulletins. They are publicly available statements from the companies that designed and built these vehicles, telling the industry exactly what a proper repair requires.

What Happens When Shops Deviate

When a repair shop does not follow OEM procedures, the consequences range from reduced vehicle performance to genuine safety hazards:

• Structural integrity is compromised. Improper welding, incorrect sectioning, or wrong adhesives can create weak points in the vehicle’s crash structure. In a secondary collision, the vehicle may not absorb and distribute energy the way it was designed to — putting occupants at greater risk.
• ADAS systems malfunction. If sensors are not recalibrated after structural or panel work, safety systems like automatic emergency braking, blind-spot monitoring, and lane departure warning may perform unpredictably. As we detailed in our article on what happens when calibration is skipped, there is often no dashboard warning when these systems are operating outside their parameters.
• Warranty claims are denied. If a component fails and the manufacturer determines the prior collision repair did not follow OEM procedures, the warranty claim can be denied. The vehicle owner — not the shop and not the insurer — bears that cost.
• Liability shifts to the shop. If a repair that deviated from OEM procedures contributes to a subsequent injury, the repair facility faces significant legal exposure. Plaintiff attorneys increasingly use OEM repair procedures as the standard of care in litigation.
• Vehicle value drops further. A repair performed outside OEM specifications is, by definition, a substandard repair. This compounds the diminished value that already results from a collision history.

“We Don’t Pay for That” — The Insurance Pushback

Here is where the conflict arises.

OEM procedures often require steps that add time and cost to a repair. Scanning, calibration, specific parts, approved adhesives, test drives, re-inspections — all of these are legitimate repair operations, and all of them appear on a repair estimate as line items that increase the total.

Insurance companies sometimes push back on these line items. Common responses include:

• “We don’t pay for post-repair scans — the shop should include that in their overhead.”
• “Calibration is not necessary for this type of repair.”
• “We only pay for aftermarket parts on this component.”
• “OEM procedures are just recommendations — they are not legally required.”

That last statement deserves special attention, because it is technically accurate and profoundly misleading at the same time.

There is no law in most states that says “you must follow OEM repair procedures.” But OEM procedures represent the manufacturer’s engineering standard for safe repair. When a shop deviates from them and something goes wrong, the question in any courtroom or regulatory proceeding is: did you follow the manufacturer’s instructions?

The manufacturer designed the vehicle. The manufacturer tested the vehicle. The manufacturer published how to repair the vehicle. An insurer’s cost analyst did not. Arguing that OEM procedures are optional is arguing that the people who built the vehicle do not get to say how it should be fixed.

How to Verify Your Repair Followed OEM Procedures

Vehicle owners rarely have the technical knowledge to audit a collision repair themselves. But you can ask the right questions and request the right documentation:

1. Ask your shop: “Did you look up and follow the OEM repair procedures for my specific vehicle?” This is a direct, reasonable question. A reputable shop will say yes without hesitation. If the shop seems uncertain or dismissive, that is a signal.
2. Request documentation of pre-repair and post-repair scans. These should be printed reports showing diagnostic trouble codes found before the repair and a clean scan after. If no scans were performed, ask why.
3. Ask for calibration records. If any ADAS component was disturbed — including bumper covers, windshields, cameras, radar modules, or structural components — calibration should have been performed. Ask for the calibration report.
4. Request a copy of the final repair order. This document lists every operation performed, every part used, and every sublet service (like calibration or scanning) that was outsourced. Compare it against the insurance estimate — if the estimate did not include scanning or calibration and the shop did not add it as a supplement, those steps may have been skipped.
5. Check the parts. Ask whether OEM or aftermarket parts were used, particularly in areas near ADAS sensors. Our article on aftermarket parts and ADAS explains why this matters for both safety and value.

What to Do If Your Insurer Says OEM Procedures Are Not Required

If your insurance company — or their adjuster, or their DRP shop — tells you that OEM repair procedures are not necessary, here is a practical path forward:

1. Get it in writing. Ask the adjuster to put their position in writing: that they are declining to pay for a repair step that the vehicle manufacturer says is required. Most adjusters will not put that in writing, because they understand the liability implications. If they do put it in writing, that document becomes evidence.
2. Reference the manufacturer’s position statement. These are publicly available. Print the relevant statement and include it with your supplement request or demand letter. It is difficult for a carrier to argue that calibration is unnecessary when Honda, Toyota, or GM has published a document saying it is required.
3. Contact your state’s Department of Insurance. If an insurer is systematically refusing to pay for manufacturer-required repair procedures, it may constitute an unfair claims practice. File a complaint with specific documentation — the OEM position statement, the insurer’s denial, and the repair estimate showing the excluded operation.
4. Document the gap for a diminished value claim. If your vehicle was repaired without following OEM procedures — whether because the insurer refused to pay or because the shop cut corners — that fact is relevant to your vehicle’s diminished value. A repair that does not meet the manufacturer’s standard is, by definition, a repair that leaves the vehicle in a compromised condition.

The Liability Question No One Wants to Answer

Here is the question that sits underneath all of this:

If a vehicle is repaired outside OEM procedures, and that vehicle is involved in a secondary collision where someone is seriously injured, who is responsible?

The shop that performed the repair? The insurer that refused to pay for the correct procedure? The vehicle owner who accepted the repair without asking questions?

This question is being litigated right now, across the country. And the trend is clear: courts and juries are increasingly holding repair facilities — and in some cases insurers — accountable when repairs do not meet manufacturer specifications and someone gets hurt.

You do not want to be the test case. And you do not want your family riding in a vehicle that was the test case.

The Bottom Line

OEM repair procedures exist because the people who designed your vehicle know what it takes to put it back together safely. Following those procedures is not a luxury — it is the baseline for a proper repair.

When an insurance company says those procedures are optional, they are prioritizing cost over safety. When a shop skips them, they are prioritizing speed over responsibility. And in both cases, the vehicle owner is the one who absorbs the risk.

Know what your vehicle requires. Ask the questions. Request the documentation. And if something was missed, address it before it becomes a safety issue instead of a paperwork issue.

Concerned About Your Repair?

If your vehicle was in a collision and you are not confident the repair followed OEM procedures — or if aftermarket parts were used near ADAS sensors — a professional appraisal can document the impact on your vehicle’s safety and value.

Request your appraisal here — and make sure the repair your vehicle received is the repair it deserved.