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2026. 10. 24. 작업

난이도 & 준비물

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a lovely ownership back story and an epic car. I look forward to reading about your progress with the XJS

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GeniusOfLove said: The facelift XJR-S came from the same period as your car I think, where the cars had the facelift but still had rubber bumpers, although they were changing things every half model year right up until the car went out of production.I found my old post at the time:"I've finally found the time to investigate the radio issues in depth. It turns out that the ignition switched 12V supply never switched on. To "fix" this issue someone has at some point just joined the permanent 12V feed to the switched feed with a scotch block so the radio will power up. Downside of this, as mentioned, is that it keeps blowing the little 5 amp fuse for the radio memory circuit. As a temporary fix I admit that I put in a bigger fuse. We'll come back to this.After some investigation of the wiring diagram it turns out that the switched 12V feed to the radio comes (inexplicably) through the heated seat relay. Heated seats don't work, although they did work one time I tested it. Ah, yes, that would be because the common output from the heated seat relay to the radio and the seat heater control modules was getting +12V from the scotch blocked connection at the radio loom! No wonder those fuses didn't last long.Anyway that relay is dead. It's a fairly common 30amp 5 pin relay commonly used as a fuel pump relay, with a common output rather than a switchover output so I should be able to pick one up tomorrow. Oh and one final finding was that the amplifier switch-on output from the head unit had been inexplicably wired to the lighting control wire on the cars loom.The more time I spend poking around under the dash and in the innards of this car the more I appreciate how far things have come in terms of the quality of engineering in automotive electronics.""The only "modification" was the splicing together of battery and ignition switched 12V feeds on the audio loom. It was Jaguars clever idea to run the switched circuit for the radio through the seat heater circuit. Only the top