AFT_B912

DECEMBER/JANUARY 2020 AFTERMARKET 29 EYEBROW www.aftermarketonline.net inspect where each item was in the vehicle and how accessible they were. Following the wiring diagram, it showed two separate wires leaving the fuse box from the same fuse and two components on each wire. My ideal test would be to remove the connector with those wires in it and see if the fault could be traced to one wire. As accessing the fuse box meant I needed to strip multiple dashboard panels I decided to unplug each component first as access was easier. After removing every component, the short was still present so this narrowed it down to a wiring issue or the fuse box itself shorted internally. By this time my initial hour was up so the customer was contacted and I explained my findings and asked for another two hours to be authorised to continuing fault-finding and time to rectify the issue once found. The customer gave the go-ahead so I then decided the next test point would be at the back of the fuse box. After stripping those multiple panels and brackets, I plugged the connector into the rear of the fuse box and found the bulb went out, indicating my short had gone. I then used a test lamp and connecting to battery positive touched each of the two connector wires which fed the components on the circuit. On touching the first pin my lamp did not light. When it touched the second my lamp did light up. This indicated the short was on that wire as my test lamp was finding a path to ground. Consulting the wiring diagram, it was found the wire was green and orange and fed the pressure switch and AC/relay both under the bonnet. As I had already disconnected both, the only possible fault could be the wire itself. The technical info however did not clearly show the location of the loom and how it was routed so a visual inspection was required. Tracking the loom, I found it went out through the driver’s side A-pillar along the inner wing and across the front lower cross member channel then up to the nearside where both components were located. I then carefully inspected the loom for possible touch points where the loom moving could rub through and cause the issue, but everything looked good. I then carried out gentle wiggle testing of the loom to see if I could find an area where the bulb would either go out or flicker for direction where the issue lay. Upon moving the loom around the driver’s headlight, I could make the light flicker slightly but not go out. Looking down at the loom, all seemed ok visually and the routing of the loom didn’t foul anything and had not been moved or altered . Support bracket The loom then went down under the headlight where I could not reach and then down the side of the radiator assembly so I decided to raise the vehicle and have another good inspection around the area where I could make the bulb flicker. Upon removing a plastic splash shield cover I found the issue I had been looking for (fig 2) At some point in this vehicle’s life the screen wash bottle had been broken and whoever had carried out the repair decided to fabricate their own support bracket with new self-tapping screws through the body where Subaru had not intended them to go! I then let the vehicle back down and removed some parts in the engine bay to allow the loom to be removed from its securing clips and be inspected. As can be seen in fig 3, one of the self-tapping screws went into the loom and caused considerable damage. The funny thing is because it went into the middle of the loom and where I could not reach it, visually it wasn’t easily spotted. Stripping back the loom found the green and orange wire I was chasing and other wires melted and exposed. Completing the fix After repairing this section of loom, insulating it and replacing the screw with a more appropriate repair the car was reassembled and a new fuse was fitted and a system check was carried out. The fuse now did not blow and the system worked and the cabin was ice cold in no time. When closing the doors and locking the vehicle with the key, the central locking system now also worked as intended as did the indicators, thus completing the fix. The other damaged wires in the loom clearly were part of those systems and causing the strange electrical issues the customer was experiencing. Like my last article this again highlights how methodical thinking, having the correct information and a test plan to follow help massively to fix every and any type of fault! A delighted customer was then notified the vehicle was fixed, and I moved onto my next job! Yes you guessed it; another short circuit and blown fuse. Above: Fig. 3