Lost all power honking horn

[Docadams]

So 72 NYer decided after honking the horn for the first time in what seems 20 years, that it would lose all power. Checked battery, good, checked wiring and all appears good, fusible link looks solid but might replace because appearances can be deceiving. Checked power to inside and outside from the bulk connector and it’s all there. Any idea what I could be missing? Haven’t checked the ammeter just yet.

 

[3C's & a D?]

Horn relay, beside or around fuse box.

 

[Docadams]

Horn relay, beside or around fuse box.

The actual relay going bad itself would cause no electrical throughout though?

 

[3C's & a D?]

The actual relay going bad itself would cause no electrical throughout though?

I'm no expert, but I would think yes. I was mostly responding to the "what I could be missing" part of your question, as it wasn't listed in your diagnosis.

 

[D Cluley]

Do you have one of those test lights with the probe on the end and a wire with a clip?

1. Hold the clip to the negative post on the battery and touch the probe to the positive post. If it lights, then the battery is good.

2. Clip to the actual end of the negative battery cable and touch the probe to the positive post. If it lights then the ground cable is connected to the battery.

3. Clip to a clean piece of metal or fastener on the engine and then the body. Touch the probe to the postive post both times. If it lights you have a good ground path.

4. Leave the clip to that good ground path and start following the positive wire with the probe. Positive battery connection, starter relay, bulkhead connection, fuse box etc. When you find a spot that the light doesn't come on, the problem is in that last segment.

You may need to add another piece of wire between the clip and your ground if you have to reach across the engine compartment or into the car.


Lots of things could be the problem, but I won't be surprised if it is just loose/dirty connections right at the battery. I've had cases where power was fine until trying to turn the engine over and then it all goes dead. Tightened the battery terminal connections and it was fine again.

 

[jimmyessbee]

My money is on a bad ground.

 

[65Port]

Agree on ground or ammeter problem. With the key off, do the brakes come on when the pedal is pressed? Headlights Total loss of power mean all electrical including motor?

 

[jimmyessbee]

Agree on ground or ammeter problem. With the key off, do the brakes come on when the pedal is pressed? Headlights Total loss of power mean all electrical including motor?

And the ammeter could be easily checked. If we jump the poles on the starter relay and it tries to start (make sure it's in park), then it's likely to be the ammeter because the starter does not go through the ammeter. But, if there's nothing when you do that as well, we know there is not sufficient ground to do anything and it's almost certainly a grounding issue. Or maybe even a positive terminal issue.

 

[Docadams]

And the ammeter could be easily checked. If we jump the poles on the starter relay and it tries to start (make sure it's in park), then it's likely to be the ammeter because the starter does not go through the ammeter. But, if there's nothing when you do that as well, we know there is not sufficient ground to do anything and it's almost certainly a grounding issue. Or maybe even a positive terminal issue.

So attempted this and nada. So going though the grounds, is there possibly somewhere in missing other then my main ground and grounds on each fender?

 

[jimmyessbee]

So attempted this and nada. So going though the grounds, is there possibly somewhere in missing other then my main ground and grounds on each fender?

If there is no power to the starter relay, these are the places that could have bad connections:
1. Positive battery terminal.
2. Negative battery terminal.
3. Ground cable to the block
4. Ground strap from block to chassis. (both ends)
5. The relay itself might not be grounded.

That's the order in which i would check them.