740 t fuel pump relay jumper
#1
#3
30 to 87/2 should manually power the fuel pumps, but the engine won't run, unless you also connect 30 to 87/1
pin 30 is unswitched power right off fuse 1.
pin 87/2 goes to the main fuel pump, fuse 11 which then goes to the tank fuel pump, and 87/2 also goes to the o2 sensor heater circuit.
if you are blowing fuse 1, then you either have a short to ground in the wiring to the above circuits, or one of those devices is shorted to ground.
1986 is at the tail end of the 'biodegradable wiring harness' years for Volvo (mid year 87 was the end).
pin 30 is unswitched power right off fuse 1.
pin 87/2 goes to the main fuel pump, fuse 11 which then goes to the tank fuel pump, and 87/2 also goes to the o2 sensor heater circuit.
if you are blowing fuse 1, then you either have a short to ground in the wiring to the above circuits, or one of those devices is shorted to ground.
1986 is at the tail end of the 'biodegradable wiring harness' years for Volvo (mid year 87 was the end).
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