What is the BTN fuse in the main box of the capri

according to manuel it is the alternator fuse might be a short or ground or just a bad alternator Hopr this helped just get the alternator tested, Good Luck Mike L.

Should be under the dash on the outside of the steering column on the drivers side.

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Fuse diagram for 1990 Ford Capri convertible

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Fuse diagram ford capri

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1990 Ford capri fuel pump fuse

The fuse box is under the dash, drivers side, towards the left. The window fuse is a 30 amp that powers both windows.

There are lots of other reasons these Capri windows stop working, from bad switches to broken motor regulators.

If the fuse does not fix it, post again and we can figure out what is wrong...Chris

Injectors get their power from the main relay and get their ground signal from the computer. The power to the injector wire is BK/W , The input power wires to the relay are blue. Jump these two wires to bypass the relay. The blue wire gets it's power from the EGI fuse in the engine compartment fuse box. If fuse is ok, jump a 12 volt source wire to terminal on relay to repair problem.
Capri main relay
This Mercury Capri main engine control relay is located under/behind the LH headlight (bucket) and interfaces with the PCM/ECU. this is a double relay.... one set of contacts according to the wiring diagram. runs just the injectors.. the other set run a bunch of other devices on the motor.
According to the manual the STO (self test output) of the ecu/pcm....when tested...is supposed to read STO low or 0 volts and if anything would be wrong the needle on an analog V ohm meter will sweep back and forth from low to 12 volts to spell out the
code for the problem. When it stays at 12v would that indicate that the PCM is bad?? Check the main relay that is located behind the drivers side headlight can but to do so remove the coolant overflow bottle. In the process of testing, check for corrosion on the blue wire that goes into the green three wire connector.repair any brakes in the wires

http://www.techcapri.com/PDF/Repair/Capri_SM_Wiring_Circuit_Protection_S18-01.pdf

this fuse supplies power to the paseenger compartment fuse box
4 BTN 40 amp Maxi fuse si Passenger
compartment fuses supplies
2, 6, 12, 13, 7

BTN stands for Body/Tail/iNterior. It protects the HAZARD, ANTENNA, ROOM, STOP, ILLUM and ABS fuses in the cabin fuse box, which in turn protect the hazard lights, antenna, ECU memory, brake lights, tail lights, ABS, power locks, clock, horn, illumination, stereo, HVAC, interior lights and alarm. __________________