Testing C1 (1960) wiring harness

[Donald H.]

I would like to test my wiring harness and connections before I install the engine. Main reason is that if something is wrong, especially in the engine bay, it sure is easier to work on the harness with the engine out. I'm in the last stages, HOPEFULLY, of finishing my restoration. But I have not installed the engine/transmission yet.

I Think I can do the following which will allow me to test the harness for at least the lights, horns, turn signals, dash lights, etc.

1 Jumper negative battery terminal to frame
2 Connect other non-frame grounds to ground (e.g. the normal valve cover grounds like the wiper motor)
3 Connect the wiring harness wire that normally goes to the solenoid B connector to battery positive
4 I have the voltage regulator mounted to the inner fender and the wiring harness connected to it, but since the engine is not in, I don't have the VR connections to the generator
5 Don't have the coil in so wiring harness to coil connections are not made and distributor are not made


Will this work, or am I missing something? Again, I'm just trying to test all the lights, horn, etc.

Thanks,

Don Harris

[Jim L.]

Re: Testing C1 (1960) wiring harness

If there is an error in the harness, the battery can source enough current to fry the wiring.

I suggest substituting a low Amperage battery charger for the battery. If there is a short, you'll see a high current draw on the meter on the charger but you won't risk frying anything.

Jim

[Donald H.]

Re: Testing C1 (1960) wiring harness

If there is an error in the harness, the battery can source enough current to fry the wiring.

I suggest substituting a low Amperage battery charger for the battery. If there is a short, you'll see a high current draw on the meter on the charger but you won't risk frying anything.

Jim

Good suggestion. I'll have to see if I can borrow a charger. All I have is a battery tender.

[Thomas H.]

Re: Testing C1 (1960) wiring harness

You could also put a 10 or 15 amp fuse in line with the battery.

I used an external 10 amp power supply when I checked my harnessing out and it worked fine.

Tom

[Donald H.]

Re: Testing C1 (1960) wiring harness

You could also put a 10 or 15 amp fuse in line with the battery.

I used an external 10 amp power supply when I checked my harnessing out and it worked fine.

Tom

That's what I will do since I don't have a proper battery charger to use or any other 12V power source. I'll pick up an inline fuse holder and do that.

Thanks,
Don

[Dan D.]

Re: Testing C1 (1960) wiring harness

A fuse will work for everything except the horns. The horns draw high current and will blow the fuse, so either don't check them, or leave them disconnected. You can listen for the horn relay to pull in. If it does, then just assume the horns will work. Fixing the horns, if necessary, does not matter if the engine is in or out. -Dan-

[Donald H.]

Re: Testing C1 (1960) wiring harness

A fuse will work for everything except the horns. The horns draw high current and will blow the fuse, so either don't check them, or leave them disconnected. You can listen for the horn relay to pull in. If it does, then just assume the horns will work. Fixing the horns, if necessary, does not matter if the engine is in or out. -Dan-

Once I test everything but the horns and nothing blows the fuse, is there any reason not to then remove the in-line fuse, reconnect the battery and test the horns?

[Dan D.]

Re: Testing C1 (1960) wiring harness

Don, the only thing to be careful of is make sure the horn wires are not reversed. You did not say if you have a new wiring harness, but I am assuming that you do. If the horn wires are reversed, then you will have big time arcs and sparks. My guess is it will destroy the horn relay, but I do not know this for a fact.

I would suggest you 'tap' the horn button first. If the horns 'toot' for an instant, then you are probably good to go. -Dan-

[Gene M.]

Re: Testing C1 (1960) wiring harness

Don, follow the wiring harness diagram in the manual and ring out each wire end to end with a volt ohm meter. This is the only way to test out the harness. Having the components plugged into the harness negates this task.

[Donald H.]

Re: Testing C1 (1960) wiring harness

Yes, i installed new Lectric Limited wiring. I'll ffollow your suggestion testing the horns.

[Philip P.]

Re: Testing C1 (1960) wiring harness

After you get the harness installed for real there is NO protlection from the battery to the fuse panel or the non fused points in the car, I would install a circuit breaker, fusible link or a fuse in the main line, The use of a ohm meter as Gene suggests is the best way to start,
MY 2 cents
Phil

[Donald H.]

Re: Testing C1 (1960) wiring harness

After you get the harness installed for real there is NO protlection from the battery to the fuse panel or the non fused points in the car, I would install a circuit breaker, fusible link or a fuse in the main line, The use of a ohm meter as Gene suggests is the best way to start,
MY 2 cents
Phil

Unfortunately I've already got all the harnesses installed and connected, so checking continuity would be difficult. I'll check what I can as Gene suggested. If I put a 'Main' fuse I assume that I could put it on the wire at the Solenoid B terminal as I believe that is where the harness get energized from the positive side of the battery. What size fuse should I use? I have an inline fuse that I am going to use temporarily to test everything but the horn.

Dan said that the horn draw a high current, so I'm wondering how I can fuse the whole harness and still get the horns to work. Is it just a matter of using a higher rated fuse?

I was not familiar with fusible links, but just did some research. Look like I can put a 16 ga fusible link on the 12 ga wire at the Solenoid B terminal and get the protection you suggested. But will it allow the horns to work or will they blow the fusible link.

I do plan to have the car judged, so I'm not sure what the fusible link will do for judging!!!

Thanks,

Don

[Philip P.]

Re: Testing C1 (1960) wiring harness

I installed a 35 amp circuit breaker this may be a little high but it is what I used. It is in the line that goes from the connection at the starter to the the amp guage (black wire), this protects the whole car. I can not remember of hand the exact current draw but the horns are probably not more than 10 amps which normally is intermitant. I also put a disconnect switch in this line kind of a safety/anti-theft device. I read some where that protection devices would not be deducted in judging but I cannot verify that.
Phil

[Joe M.]

Re: Testing C1 (1960) wiring harness

Donald, I learned the value of having a fusible link at the solenoid the hard way. I had a major electrical short that burned the entire wiring harness in less than 5 seconds. By the time you raise the hood, the damage is done. My mechanic installed the fusible link; I don't remember what size fuse he installed.