Hi. This is my first time doing this so if I'm doing it wrong let me know. I just purchased a 1989 Volvo 240 DL that the previous owner says the inline fuse at the battery keeps blowing. He reported history of the car is as follows- the car was running fine but he noticed the voltmeter was indicating 12 volts and it seemed like the car was taking longer to start. Change the voltage regulator and started the car on the first attempt. He then disconnected the battery cables and the car died. He discovered the inline fuse has blown so I put another one in. Attempted to start car with no start but engine turns over. Fuse blows again. He then changes fuel pump relay same thing. He then changes ECU same thing. He then becomes frustrated and sells the car to me for a deal. The car blows the fuse as soon as the ignition switch is turned on before before engine turns over. I have disconnected both fuel pumps if you still blows. When I disconnect the ECU the fuse does not blow. I have the old ECU that he replaced and when I hook it up to that the fuse blows. I have limited electrical experience but can operate a multimeter four simple checks. I don't have a book with a wiring diagram and even if I did probably couldn't read it. Any ideas where should i start.?