Bronco_69
Bronco Guru
This is a plug in and ride for a 1975 bronco and almost anything else. Here are the connections needed. This harness will bolt in a matter of minutes. all connections are clearly labeled for an easy install.
There is a 3 wire connection to the left of the throttle lever on a 75 bronco. that is where you plug in the oil pressure, water temp, and 12 volts crank/run on the bronco. if you do not have this plug then you will have to wire that. the 12v crank and run is the 12v+ wire going to your coil.
here are the harness connections. all connections will be labeled.
1. battery side of starter soleniod (harness power)
2. 3 Ground wires.
3. HEGO ground (O2 sensors)
4. crank and run (your old coil wire)
5. crank 12v source (on the starter soleniod)
6. oil pressure (optional, these are wired in the 3 wire plug mentioned)
7. water temp (optional, these are wired in the 3 wire plug mentioned)
8. your fuel pump wire to the output on the relay (relay provided and and wired)
there are 3 relays in this harness. one for the EEC, one for the Fuel pump, and one for HEGO's. the relays are included and fulley wired.
if your bronco has the 3 wire plug (for the oil,water, and coil) that looks like a trailer plug then this will be a plug in and go harness.
it is set up for mass air or speed density computers but i must know if you have a manual or automatic computer.
I can set it up for a manual or automatic computer. It must be set up for the manual or automatic to read codes. If you are not sure what computer you want i can write directions for you to connect it. for an auto computer wire 30 (clearly labeled) needs 12v and for a manual computer it need to be connected to pin 46. The 12v wire and pin 46 wire are built into the harness and clearly labeled. it would take 2 minutes to connect to right wire.
i can get you the speed density computer for $40 more.
this harness is set up for a drivers side throttle body but can be made for a passenger side throttle body. the drivers side works great. it provides lots of room and allows you to use a stock mustang throttle cable with a mustang throttle body and cable bracket.
the harness to body grommet is also included. all you need is a 1.5" hole saw to drill a couple holes. connect the holes and you have a weather tight seal.
the O2 harness is there and so is the injector harness.
any questions ask.
here is MY bronco with a harness that i built.
Now this is a USED OEM harness that has been modified. it does have some broken clips and such.
all wiring connections made by me are soldered and heat shrinked and then tapped.
here is the harness
here is the 3 wire plug that will plug in at your firewall.
battery, 12v crank, and ground connection
O2 sensor connections, VSS connection, and 12' of heavy duty 12 gauge wire to your fuel pump
computer connection and case ground
There is a 3 wire connection to the left of the throttle lever on a 75 bronco. that is where you plug in the oil pressure, water temp, and 12 volts crank/run on the bronco. if you do not have this plug then you will have to wire that. the 12v crank and run is the 12v+ wire going to your coil.
here are the harness connections. all connections will be labeled.
1. battery side of starter soleniod (harness power)
2. 3 Ground wires.
3. HEGO ground (O2 sensors)
4. crank and run (your old coil wire)
5. crank 12v source (on the starter soleniod)
6. oil pressure (optional, these are wired in the 3 wire plug mentioned)
7. water temp (optional, these are wired in the 3 wire plug mentioned)
8. your fuel pump wire to the output on the relay (relay provided and and wired)
there are 3 relays in this harness. one for the EEC, one for the Fuel pump, and one for HEGO's. the relays are included and fulley wired.
if your bronco has the 3 wire plug (for the oil,water, and coil) that looks like a trailer plug then this will be a plug in and go harness.
it is set up for mass air or speed density computers but i must know if you have a manual or automatic computer.
I can set it up for a manual or automatic computer. It must be set up for the manual or automatic to read codes. If you are not sure what computer you want i can write directions for you to connect it. for an auto computer wire 30 (clearly labeled) needs 12v and for a manual computer it need to be connected to pin 46. The 12v wire and pin 46 wire are built into the harness and clearly labeled. it would take 2 minutes to connect to right wire.
i can get you the speed density computer for $40 more.
this harness is set up for a drivers side throttle body but can be made for a passenger side throttle body. the drivers side works great. it provides lots of room and allows you to use a stock mustang throttle cable with a mustang throttle body and cable bracket.
the harness to body grommet is also included. all you need is a 1.5" hole saw to drill a couple holes. connect the holes and you have a weather tight seal.
the O2 harness is there and so is the injector harness.
any questions ask.
here is MY bronco with a harness that i built.
Now this is a USED OEM harness that has been modified. it does have some broken clips and such.
all wiring connections made by me are soldered and heat shrinked and then tapped.
here is the harness
here is the 3 wire plug that will plug in at your firewall.
battery, 12v crank, and ground connection
O2 sensor connections, VSS connection, and 12' of heavy duty 12 gauge wire to your fuel pump
computer connection and case ground