A minor rear-end collision may not look like it caused any damage, but you should still take the car into the shop for an inspection. There are several types of collision damage that are common, even at low speeds.
1. Bumper Damage
Most modern cars have a plastic bumper cover shielding the actual bumper. In a minor collision, the plastic cover may become scratched or cracked, which may necessitate a replacement. The shop must also check the bumper underneath the cover to make sure it wasn't compressed to the point that it needs to be replaced. They will also verify that any airbag sensors in the bumper are reset following the collision.
2. Trunk Latches
One of the more obvious forms of damage from a low-speed collision is a popped trunk latch. Often the trunk won't latch properly after you have been hit. This is typically due to either damage to the latch or from the warping of the trunk or rear car body panels that prevents the latch from lining up correctly. Repair services typically include straightening the panels as well as a possible latch replacement.
3. Wiring and Lighting
Depending on the angle of the collision, you may end up with busted-out tail lights. There may also be damage to the wiring, even if the lights themselves appear undamaged. This can lead to flickering or even failed lights when the car is in motion. Your repair service must check all the wiring and internal housings for your rear lights to make sure there aren't any hidden damages.
4. Frame and Alignment
Modern car frames are designed to absorb an impact in order to minimize the chances of injury to those inside the vehicle, which can skew the frame. The car may look fine from the outside, but the alignment of the tires will often be off and the car will begin to pull to one side. Fortunately, most newer car frames are designed in a way that they can be pulled back into shape by the repair shop. After the frame is repaired, the wheels will be properly aligned.
5. Suspension Issues
Rear suspension often suffers some damage, even in a low-speed collision. Struts and shocks may become damaged or be knocked loose during the accident. Frame damage can also affect the suspension. Much like alignment issues, the suspension issues can only be repaired after the frame is straightened back out.
Contact an auto collision repair service for more help if you have been rear-ended.