A knock in a car park, a clumsy reverse against a pillar, or a stone off a truck tyre — and suddenly your wing mirror is in three pieces on the road. The natural reaction is to search for "side mirror replacement" and buy the first thing that fits your car. That is usually the most expensive way to solve the problem.
An outside rear-view mirror is not one part. It is a small assembly made of separate, individually replaceable pieces. Work out which piece actually failed and you can often spend a fraction of what a complete unit costs. This guide explains the three levels of replacement — glass, cover and full assembly — and how to decide between them.
The three parts of a side mirror
1. The mirror glass (sub mirror)
This is the reflective glass panel itself, usually bonded to a plastic backing plate that clips or sticks onto the motor. On German cars it is commonly heated, so it also carries two small electrical tabs. If your glass is cracked, crazed, delaminating at the edges or has simply fallen out, this is all you need.
2. The mirror cover (cap or housing)
The painted or textured shell that clips over the outside of the mirror. It takes the impact in most minor collisions and is purely cosmetic — it holds no electronics. A scuffed, cracked or missing cover does not affect how the mirror works, only how it looks.
3. The complete assembly (ORVM)
The whole unit: base, arm, motor, glass, cover and wiring plug. This is what you need when the internal motor has failed, the folding mechanism is stripped, the mounting base has snapped, or the arm itself is bent. It is by far the costliest option, which is exactly why it should be your last choice rather than your first.
How to work out which one you need
Sit in the driver's seat and run through this quickly before you order anything:
- Does the mirror still adjust with the switch? If the glass tilts up, down and sideways when you press the adjuster, the motor is fine — you do not need an assembly.
- Does it still fold in and out? If the folding motor whirs and moves, the assembly is healthy.
- Is the damage only to the reflective surface? Cracked, shattered or fogged glass with a working motor behind it means you only need the glass.
- Is the damage only to the outside shell? Scratched or broken paintwork on the shell, with everything working, means you only need the cover.
- Does the mirror hang loose, vibrate at speed, or do nothing at all when you press the switch? Now you are likely looking at the full assembly — or at least a wiring or fuse problem worth checking first.
One more check worth doing: if the mirror is dead electrically, test the other side. If both mirrors are dead, the fault is far more likely to be the mirror adjuster switch or a fuse than two failed motors.
Getting the specification right on mirror glass
Mirror glass looks like the simplest part to buy and catches out more people than any other. The same car and the same year can have several different glasses depending on how it was specified. Before ordering, confirm:
- Side. Left and right are not interchangeable. Note whether the seller lists sides by driver or by direction of travel, and confirm which one you actually need.
- Heated or not. Heated glass has electrical connectors on the back. Fitting non-heated glass to a car with a demister circuit means losing the function.
- Single or double curvature. Many European cars use aspherical (double curvature) glass on one side to widen the field of view, often with a line etched on the surface. Fitting flat glass in its place changes what you see.
- With or without a plastic frame or backing plate. Some glasses come as a bare panel, others as glass already bonded to the carrier that clips into the mirror.
- Blind-spot or auto-dimming. If your car has these features on that side, the glass must support them.
Getting the specification right on a full assembly
Complete mirror assemblies are matched to the options your particular car was built with. The plug is the giveaway: assemblies are usually described by pin count, and the number of pins tells you which functions the mirror supports — heating, power folding, memory, puddle lamp, indicator repeater, blind-spot monitoring. A mirror with fewer pins will physically plug in on some cars but will not give you every function, and a mismatch can leave a warning on the dash.
So count the pins in your existing connector, note every feature your mirror currently has, and match all of it. Also check whether your car's covers are painted to body colour — many aftermarket assemblies arrive in primer or black and need painting to match.
Always check fitment before you pay
Whichever level you buy, verify it properly. Start with your make, model, body code and year — a BMW 3 Series E90 and an F30 share nothing here, and mid-life facelifts often change the mirror too. Then cross-check the OEM number stamped on the part you are removing, or read it off your VIN in a parts catalogue. Model year alone is not enough; the OEM number is what settles it.
If you are unsure, take a clear photo of the back of the existing glass and of the connector plug before ordering. Between those two images and your VIN, any decent parts supplier can confirm the right item.
Fitting notes
Mirror glass is usually the easiest job on the car: warm the panel gently, tilt it fully in one direction, ease the opposite edge free with a plastic trim tool, unclip the heater tabs and press the new one on until it clicks. Take your time in cold weather, as cold glass cracks more readily. Covers generally unclip once the glass is out. A full assembly means removing the door card or an inner trim triangle to reach the plug and fixings — straightforward on most cars, but budget an hour and a set of trim tools.
The short version
Cracked glass, working motor — buy the glass. Scuffed shell, everything working — buy the cover. Dead motor, snapped base or bent arm — buy the assembly. Working through it in that order is the difference between a modest bill and a large one.
Find the right mirror part
German Purje stocks replacement mirror glass and complete ORVM assemblies for BMW, Mercedes-Benz, Audi, Porsche and Volkswagen, listed by model and year so you can match yours precisely. Browse our replacement mirror glass collection, or go straight to your car: BMW parts and Mercedes-Benz parts. Popular complete units include the BMW 3 Series F30 left ORVM assembly and the Mercedes C-Class W205 left ORVM assembly.
Not sure which version fits? Send us your VIN or a photo of the old part and we will confirm it before you order.