scottmcwms
Sr. Member
Today I was going to try to start my Bronco after a long frame-off restoration. I can't get the motor to turn over. I'm definitely not an electrical genius so I need some help. Here is what I did electrically during the restoration.
new battery
new battery cables
old alternator
old starter
new Pertronix Ignitor
new Pertronix coil
all old switches except the emergency flasher switch
I "rewired" using an economy wiring harness. I have a feeling this is where my problem lies.
new starter relay
new voltage regulator
Everything else is original except a new steering wheel with a new horn switch.
Here is what happened.
I got everything hooked up and my last connection was the + battery cable. As soon as the cable was touching the battery, I heard an arcing sound. I chased it down and found it coming from the steering column. I removed the new steering wheel and found the horn switch completely melted. When I installed the horn switch I didn't pay any attention to how the switch was connected. I just plugged the two prongs into the two wires and called it good. Did I do something wrong here???
I disconnected the horn switch and tried to continue from here. I turned the key and nothing happened. Here are my observations:
headlights - working
headlight dimmer switch - working
parking lights - working
emergency lights - working
turn signal indicators - not working
heater - not working
wipers - not working
So I decided to chase down the electrical path and see where it led me. I started with the starter relay. I disconnected the starter motor lead from the relay and touched to directly to the + battery post. The starter turned over and cranked the motor. So I know the starter motor is OK.
Then I touched the + battery post of the relay to the terminal on the front of the starter to bypass the ignition switch and nothing happened. I pulled out my multimeter and did some checking.
The battery was reading 15 volts from post to post. With the ignition switch in the off position, the potential from the + battery post to each of the relay terminals on the starter relay and the + post on the coil was 0 volts.
With the ignition switch in the run position, the potential from the + battery post to the relay terminal closest to the starter motor lead was 15 volts. The potential from the + battery post to the relay terminal closest to the battery lead was 0 volts. The potential from the + battery post to the + coil post was 15 volts.
With the ignition switch in the start position, the potential from the + battery post to each of the relay terminals and the + coil post was 15 volts.
According to the wiring schematics, I am seeing with the multimeter exactly what I should be seeing.
It seems like I should see the starter motor turn over according to what the starter relay is doing. I took the starter relay off and reinstalled the old one. I came up with the same results.
I think I found one thing I did incorrectly when I "rewired" using the economy harness. There is a wire on the harness that is supposed to run "to ignition switch run terminal". I think I accidentally connected it to the A terminal on the ignition switch instead of the C terminal.
Any ideas would help out. I will switch the ignition switch terminals tomorrow and see if that makes a difference. Does anyone have any other ideas?
Thanks,
Scott
new battery
new battery cables
old alternator
old starter
new Pertronix Ignitor
new Pertronix coil
all old switches except the emergency flasher switch
I "rewired" using an economy wiring harness. I have a feeling this is where my problem lies.
new starter relay
new voltage regulator
Everything else is original except a new steering wheel with a new horn switch.
Here is what happened.
I got everything hooked up and my last connection was the + battery cable. As soon as the cable was touching the battery, I heard an arcing sound. I chased it down and found it coming from the steering column. I removed the new steering wheel and found the horn switch completely melted. When I installed the horn switch I didn't pay any attention to how the switch was connected. I just plugged the two prongs into the two wires and called it good. Did I do something wrong here???
I disconnected the horn switch and tried to continue from here. I turned the key and nothing happened. Here are my observations:
headlights - working
headlight dimmer switch - working
parking lights - working
emergency lights - working
turn signal indicators - not working
heater - not working
wipers - not working
So I decided to chase down the electrical path and see where it led me. I started with the starter relay. I disconnected the starter motor lead from the relay and touched to directly to the + battery post. The starter turned over and cranked the motor. So I know the starter motor is OK.
Then I touched the + battery post of the relay to the terminal on the front of the starter to bypass the ignition switch and nothing happened. I pulled out my multimeter and did some checking.
The battery was reading 15 volts from post to post. With the ignition switch in the off position, the potential from the + battery post to each of the relay terminals on the starter relay and the + post on the coil was 0 volts.
With the ignition switch in the run position, the potential from the + battery post to the relay terminal closest to the starter motor lead was 15 volts. The potential from the + battery post to the relay terminal closest to the battery lead was 0 volts. The potential from the + battery post to the + coil post was 15 volts.
With the ignition switch in the start position, the potential from the + battery post to each of the relay terminals and the + coil post was 15 volts.
According to the wiring schematics, I am seeing with the multimeter exactly what I should be seeing.
It seems like I should see the starter motor turn over according to what the starter relay is doing. I took the starter relay off and reinstalled the old one. I came up with the same results.
I think I found one thing I did incorrectly when I "rewired" using the economy harness. There is a wire on the harness that is supposed to run "to ignition switch run terminal". I think I accidentally connected it to the A terminal on the ignition switch instead of the C terminal.
Any ideas would help out. I will switch the ignition switch terminals tomorrow and see if that makes a difference. Does anyone have any other ideas?
Thanks,
Scott
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