BY Frank Massey The last topic concluded with a promise to share my experiences working within a workshop lacking in essential infrastructure. I hope by explaining my failings and limited success, it helps identify the importance of correct process, correct tools and comprehensive systems information. If you forgo one or more of these three critical elements, failure is predictable even before you begin a repair task. The most basic and simple error; Failing to assess the battery rating and cell condition. Note I didn’t focus simply on voltage. The first example was a Ford Focus 1.6 ecoboost, suffering windscreen wiper failure. The car was driven to us, and the customer explained the battery had gone flat and been charged. Conductance test I began with a conductance test with my personal Midtronics MDX 600. Voltage was 12.47, rated 540 amps, however it only returned 346 amps. Please refer to Fig.1. I ordered a replacement and decided to continue testing the screen wiper problem. The vehicle started and drove into the workshop, so I began checking voltage and ground at the twin wiper motors. There was no change of state, however the voltage was below 9 volts after only a very short time. So, I fitted a temporary good battery and continued with my tests, only to find the wipers working normally. The explanation is straightforward; CAN and lower priority networks often hibernate with system voltage drop. So, my knowledge, process and tools won the day here. The next problem, another Ford Focus, had much more challenging issues. Initially it drove to us with starting problems, then failed to start. Global vehicle check I began with a global vehicle check using the garage TOPDON serial tool. It had reasonable systems access and displayed steering column communication loss with the body control module; B1026:87-2F. It showed two keys stored, and the immobiliser was registered in the PCM. We had limited wiring access via E3 tech data, but crucially no test plan data. We were dead in the water now, relying on the common-sense method. We decided to ramp the vehicle and examine wiring and PCM, located we thought under the front wheel arch. The PCM housing was damaged, probably from a light frontal impact, and had allowed water ingress. The next series of events taken over several weeks is a textbook example of how to fail in a repair and diagnostic process. 24 AFTERMARKET MAY 2023 TECHNICAL www.aftermarketonline.net A MONTH IN THE LIFE OF A VEHICLE TECHNICIAN Failure is always predictable according to Frank, so you need to learn to expect the unexpected My only satisfaction was that the decisions were not of my making. The cost of a new PCM with programming and coding exceeded £1,500. The owner could not afford the repair, so a second-hand PCM was suggested. Mistake number one; Cost must never influence correct process. A unit was sourced by the owner in Poland. Mistake number two: Never allow customer interference in the repair or part procurement process. The owner was instructed to send the original PCM to Poland so programming and coding could be transferred across. Mistake number three: Never use or trust third party contractors unless personally known to you. Although this is technically possible, and we at ADS have done this many times, you have now lost control of the repair. This mistake is fatal and has no comeback. The PCM was fitted to the vehicle and guess what? No change in the symptoms. I was then re-tasked to check the fault from the sketchy wiring schematics. I had no enthusiasm left at this point, so let’s score it as mistake number four; You need to have a positive mental attitude. My evening’s Vodka consumption didn’t help. Having Fig. 2 Part Three
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