[onemorechevelle]

Hello, New to the site. I recently purchased a 71 chevelle. about 3 weeks back my horns started going off all on there own,I was in the house. no one in or near the car. Now when I open the door the dome light is dim,pull the head light switch it goes more dim. no headlights,power to anything at all. Will not crank,etc. previous owner attempted 1 wire alt set up and was done incorrectly.I have removed the engine harness to check all wires. It is in really good condition, not chopped up. Ign switch maybe?

 

[Dean]

Battery fully charged?

 

[onemorechevelle]

yes, fully charged. when I connect the charger 2 lights on the dash light up. car will not jump start.It started when I purchased it. after the horn issue is when it would not do anything.

 

[Jim Streib]

I would go out and buy what they call a multimeter. A multimeter can do things like checking voltages, and can do other things like checking resistances (ohms). You want a meter that can check DC voltages from anywhere from 0-20 volts and then resistances from 0 ohms to infinity. Some meters are flexible too to where they can also check higher voltages and also AC as well as amperage draw.

Without a meter trying to figure out electrical will be hard to do. If you wanted to know how much a bolt or nut is torqued, you would buy the tool to check that kind of thing.

While you can get a test light also, a test light will not be as flexible or give as much information as what a meter can give.

It sounds like now with a dim dome light and no headlights you may have a battery power issue so you may want to put the battery on a battery charger to charge it up and see what happens. A battery charger may have different settings so check to see where they need to be set at. Maybe too, disconnect the battery cables off of the battery and charge the battery itself. If you are having a drain on the battery then power off of the charger will not be all going to the battery but instead into the battery and then trying to supply the power drain in the car itself.

Jim

 

[DUTCH MAX HEADWORK]

Check the connectors at the horn relay buss bar for power and make sure they are clean. Clean your batt terminals and their attachment points. Ther's a red wire that goes from the batt to the bussbar and supplies power through the bussbar connector to another wire that runs into the cab for ignition, lights and just about everything in the cab. These wires are protected by fusible links, so if you lose power in the run to the cab, your fusible link is toast.

You need a test light or ohm/voltage meter to help you find your issue. I sort of suspect the horn issue is another issue unless a power wire is shorting to the horn wire. The horn circuit receives power from the bussbar at the horn relay, there's a wire that runs to the steering wheel that once shorted activates the switch in the horn relay which powers the horn function.

What voltage are you showing at the battery?

 

[onemorechevelle]

Thanks Jim, I have tried as you have suggested. My charger has a start feature also bt nothing happens. Multi meter is on the list. Previous owner was shooting for a 1 wire alt setup and was not done correctly. had a wire going directly from battery to the alt.also 1 wire to terminal block on firewall and running to horn relay and back to alt. nothing at 2 pin connector at alt. so there were 2 wire going to alt, Dave

 

[onemorechevelle]

Battery is fairly new, has full charge. charger has jump start option,still nothing I have checked all grnd wires under the hood.

 

[blm]

Battery is fairly new, has full charge. charger has jump start option,still nothing I have checked all grnd wires under the hood.

Is it a gel battery? How do you know it has a full charge? The level of charge should be confirmed with a mutimeter.

 

[B52bombardier1]

Full charge is established with a load test for the delivery of amps, not a multimeter. A multimeter only indicates the voltage which is merely half of the equation for power. Remember - volts x amps = watts = power, the ability to do useful work.

It doesn't matter if the battery indicates 12, 13, 14 or whatever volts. If it can't deliver sufficient amps, its dead. We need volts AND a whole lotta' amps to spin a starter motor. The load test is usually a free service at any auto parts store.

Rick

 

[HKalin]

I don't know why you wouldn't have power to anything but I always ask this question first. By any chance did you mess around with the steering column. There is a collar right behind the steering wheel that has to be turned all the way counterclockwise. Try that and see if it starts.

 

[onemorechevelle]

My charger has a voltage test feature, out of the car it takes and holds a charge.

 

[onemorechevelle]

Have not messed with the column but will check

 

[onemorechevelle]

The main issue seems to be what,where and why is causing the problem. fresh charge on battery,installed in car, dome light is dim. I pulled headlight switch to on an the dome light gets so dim you can hardly see it. i disconnected the H L switch and the dome still goes dim. turn the key to start. absolutely nothing. no clicks etc. I have pulled the harness out and plan to go through it. previous owner tried to do a 1 wire alt hookup and was incorrectly wired.

 

[oldcutlass]

Did you get a volt meter? Without it we can't help you.

 

[onemorechevelle]

also, the car was starting and running before the issue with the horns going off by themselves. coincidence maybe? I don't know. I appreciate all the response to this.

 

[DUTCH MAX HEADWORK]

What does work electrically? Anything in the cab, headlights, turn signals???

At the very least you'll need a test light to find the issues. I would pull the batt and have it tested at the parts store while you are picking up a test light. This will check off a battery issue. A test meter would go a long way in helping you deal with the issues you need to iron out. 10 bucke=s is all you need for one that will do the job and we'll know what's going on and we'll be able to help with some simple tests.
'

At this point, I suspect a bad connection or fusible link running from the batt to the horn relay, or from the horn relay to the cab power supply.

I don't have a good 71 diagram, below is a 70 which is close.

We'll probably need to know what alternator you are running to see what can be done with your charging system. If you can supply a picture of the alt including any stampings on it and a good picture of the plug socket we might be able to offer advice. See if you can d\find an external regulator. It would be near the horn relay. If it's not there, a picture of the hackery done go the wiring that led to the external regulator will help.

 

[blm]

The main issue seems to be what,where and why is causing the problem. fresh charge on battery,installed in car, dome light is dim. I pulled headlight switch to on an the dome light gets so dim you can hardly see it. i disconnected the H L switch and the dome still goes dim. turn the key to start. absolutely nothing. no clicks etc. I have pulled the harness out and plan to go through it. previous owner tried to do a 1 wire alt hookup and was incorrectly wired.

The symtoms above seem to indicate a battery with a very low charge. So I would take the battery to an auto parts where it can be tested. If the battery is fully charged you will either have get your hands on a meter and chase a possible power loss down or start changing parts till you overcome the problem.
The key to finding the problem is the meter. They can be had at harbor freight for as low as $7.00.
If you do find the battery is low you can use the meter to determine what circuit is causing the amp draw and draining the battery.
Do you have another battery you can temporarily attach/touch the positive and negative cables to and see if you get the same symptoms. Maybe one from another vehicle.

 

[onemorechevelle]

Previous owner told me the battery was not very old. what I have not done is check the battery after charging out of the car and leaving it sit. Can you guys kick this around?previous owner had a wire coming off alt directly to the battery.also had 1 from alt running to horn relay and was running to block and to the battery. alt has new style 2 point connection with nothing plugged into it,internal voltage regulator?

 

[onemorechevelle]

Don't have another top post but it is on a charger right now, I have looked at and watched conversions to 1 wire alt hookups for chevys. can't help but think this one as done wrong. not shows a wire going from the alt straight to the battery.

 

[onemorechevelle]

Thanks, nothing in cab works, no headlights, turn signals etc. only the dome light. voltage reg is there and connected. I really appreciate all you guys getting with me on this. anybody done the conversion? thanks for diagram,it will help.What is your opinion on changing it back to the to original style alt and wiring? Also, will get pics of the alt that is on the car now.