When you have the dealer check the SRS system, does it normally find the specific fault? How specific and reliable is their diagnostic system?

 

Fault codes don't usually tell you what to do. They just identify the nature of the fault. e.g. Misfire
Diagnostics improve on each generation of vehicle. You don't state model age etc.

If the dealer uses STAR (MB proprietary system) it is very specific.

There are many codes relating to the SRS system. SRS is a safety system so ensuring the system will work when required to is paramount.

However diagnostics are dumb. Fault codes accurrately reflect/record a problem at a point in time but such a fault might be due to a transient condition at the extreme of the operating range. Sometimes a simple reset appears to resolve a problem without any further chance. Some people think that this means that the diagnostics are unrelaible, but this is NOT correct.

If a light comes on then SOMETHING in the system is out of range. However the conditions that caused the code may not occur again immediately, or possibly ever again.