Electrical System Failures
Tracking
electrical system failures It takes skill to traverse the correct diagnostic path By Edwin Hazzard
T Figure 1: Over time, improper harness routing can easily result in a direct short.
30
ASP
October 2018
The need to track down electrical system failures in today’s vehicles are more prevalent now than they were many years ago. With the addition of system add-ons such as increased safety items, more entertainment and creature comfort options and overall improved vehicle operating capabilities, the technician is faced with the added complexity of performing proper diagnostics. Today’s vehicles have more control modules, more wiring, more harness connections and with all of that less room in the vehicle to access these changes. A major issue is the way the vehicle manufacturers route their wiring harnesses. They are routed in such a way that they try to make it all fit in a very small, confined space. Sometimes the harness routing isn’t always optimum, and due to the cramped space and confined areas, the harnesses themselves become stressed. A harness can be so tightly routed that the wire inside of the plastic insulation can break and you won’t even see that with a good visual inspection. The opposite scenario is a harness that is routed so loosely that with vehicle vibra-
