John began work on our 1985 Daimler DS420 Limo, which had come in for recommissioning and presented several electrical issues. He first addressed the non-functional hazard lights. Upon inspection of the switch wiring, he discovered that the power supply to the switch was under 9 volts. When power was supplied directly from the battery, the hazard lights operated correctly. The issue was traced to a corroded fuse and fuse holder located behind the dash. John cleaned the connections within the holder, fitted a new fuse, and rechecked the system, confirming the hazard lights were functioning properly.
Next, he investigated the electric door mirrors, which were not adjusting in either plane. The driver’s door card was removed to access the wiring, revealing that while power was present at both switches, it was not reaching the mirror. A broken wire to the driver’s mirror was identified and repaired. John then applied electrical contact cleaner to the switch, operating it several times to clean the contacts. This restored full functionality to the driver’s door mirror.
He proceeded to carry out the same cleaning procedure on the passenger side switch, which restored only vertical adjustment. To isolate the fault, the switches were swapped. Since the replacement switch functioned correctly, the fault was narrowed down to the wiring or the mirror itself. The passenger mirror was removed and wired directly to the switch, confirming the mirror was operational. Further checks on the wiring between the switch and mirror revealed high resistance, though not a complete break. A joint behind the glovebox was located and tested for continuity, which proved satisfactory, though the connector was found to be corroded. This was cleaned and refitted, after which the mirror was reinstalled and tested, confirming it was working as intended.
Lastly, John investigated the non-functional passenger rear cigarette lighter. He swapped the element with the one from the driver’s side and verified it worked correctly. However, no power was present at the passenger socket. On removing the trim panel, he discovered that the lighter had come apart. It was reassembled, the panel refitted, and the cigarette lighter rechecked, confirming it was operational.
