C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Help Please!

Thread Tools
 
Search this Thread
 
Old 04-06-2018, 10:58 PM
  #1  
Brandon Smith
Cruising
Thread Starter
 
Brandon Smith's Avatar
 
Member Since: Apr 2018
Location: Galloway Ohio
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Default Help Please!

I’ve got a 69 Corvette I’m having issues with. Battery is Fully Charged, I even hook up jumper cables up for extra power. The only thing I can get to work is the horn! I’ve replaced al fuses, the ground wire from the battery, and even tried hooking the jumper cables directly to the started and engine block and a getting the same result. I was able to get the buzzer to come on one time, and the seatbelt light to come in but haven’t been able to replicate that again. I don’t know where to go from here. Any ideas?
Old 04-06-2018, 11:08 PM
  #2  
TimAT
Le Mans Master
 
TimAT's Avatar
 
Member Since: Oct 2006
Location: Gladstone MO
Posts: 7,121
Received 424 Likes on 385 Posts
C3 of Year Finalist (appearance mods) 2019

Default

There are 2 fusible links close to the starter, and one by the horn relay on the left inner fender. I'd start by checking them. After that, look at the connector between the dash harness and the engine side- that is a big connector basically on the back of the fuse block, accessible from the engine side.
Old 04-06-2018, 11:14 PM
  #3  
carriljc
Le Mans Master
 
carriljc's Avatar
 
Member Since: Jan 2001
Posts: 5,358
Received 879 Likes on 764 Posts

Default

Take your battery out and go to your local auto parts place and have it load tested. They will check it to ensure it is fully charged and to see if it is any good.

While you are there getting some battery terminal cleaning brushes and supplies. Clean your terminals on the battery and clean the terminals on the leads.

After you do that, then report back, and let us know how it goes.



Originally Posted by Brandon Smith
I’ve got a 69 Corvette I’m having issues with. Battery is Fully Charged, I even hook up jumper cables up for extra power. The only thing I can get to work is the horn! I’ve replaced al fuses, the ground wire from the battery, and even tried hooking the jumper cables directly to the started and engine block and a getting the same result. I was able to get the buzzer to come on one time, and the seatbelt light to come in but haven’t been able to replicate that again. I don’t know where to go from here. Any ideas?
Old 04-07-2018, 07:28 AM
  #4  
scrappy76
Drifting
 
scrappy76's Avatar
 
Member Since: Jan 2011
Location: Hamilton Virginia
Posts: 1,853
Received 78 Likes on 68 Posts

Default

Originally Posted by carriljc
Take your battery out and go to your local auto parts place and have it load tested. They will check it to ensure it is fully charged and to see if it is any good.

While you are there getting some battery terminal cleaning brushes and supplies. Clean your terminals on the battery and clean the terminals on the leads.

After you do that, then report back, and let us know how it goes.

Imo, If you are able to get items to work then not, you probably have a corroded issue or a break inside a wire. you have more wires to check besides the battery ground. you also have the grounds of the engine block itself. then you have your feeds going to the alternator.
Old 04-07-2018, 07:32 AM
  #5  
76strokervette
Burning Brakes
 
76strokervette's Avatar
 
Member Since: Nov 2011
Location: Willoughby Ohio
Posts: 1,170
Received 200 Likes on 156 Posts

Default

Originally Posted by TimAT
There are 2 fusible links close to the starter, and one by the horn relay on the left inner fender. I'd start by checking them. After that, look at the connector between the dash harness and the engine side- that is a big connector basically on the back of the fuse block, accessible from the engine side.
Old 04-07-2018, 07:45 AM
  #6  
derekderek
Race Director
 
derekderek's Avatar
 
Member Since: Jul 2015
Location: SW Florida.
Posts: 13,022
Received 3,388 Likes on 2,633 Posts
Default

Horn relay is the first thing gets power after the big top stud on the starter. You have no continuity from horn relay in to fuse box or ignition switch.
Old 04-07-2018, 11:19 AM
  #7  
henrikse
Pro
 
henrikse's Avatar
 
Member Since: Nov 2016
Location: Kelowna British Columbia
Posts: 729
Received 115 Likes on 98 Posts
Default Start at source

Originally Posted by Brandon Smith
I’ve got a 69 Corvette I’m having issues with. Battery is Fully Charged, I even hook up jumper cables up for extra power. The only thing I can get to work is the horn! I’ve replaced al fuses, the ground wire from the battery, and even tried hooking the jumper cables directly to the started and engine block and a getting the same result. I was able to get the buzzer to come on one time, and the seatbelt light to come in but haven’t been able to replicate that again. I don’t know where to go from here. Any ideas?
You need to get a DC meter to troubleshoot. Always start at source (Battery) clip on negative and check voltage then go to starter and check on battery cable there. (large cable) and then it goes to horn relay jct. You will need a schematic which are offered here for free from papawana.
The grounds on a fiberglass car are quite often the problem. When you are trouble shooting go on ground at for instance engine to check positive voltage at starter to ensure ground. WHen you find ground wires take them off and clean with emery cloth or what have you and tighten them down.
Looking at wiring rarely solves problems. A good meter or test light will tell you what you have
Old 04-07-2018, 12:26 PM
  #8  
Brandon Smith
Cruising
Thread Starter
 
Brandon Smith's Avatar
 
Member Since: Apr 2018
Location: Galloway Ohio
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Default

Where can I get a schematic for the ground locations?
Old 04-07-2018, 02:10 PM
  #9  
henrikse
Pro
 
henrikse's Avatar
 
Member Since: Nov 2016
Location: Kelowna British Columbia
Posts: 729
Received 115 Likes on 98 Posts
Default

Originally Posted by Brandon Smith
Where can I get a schematic for the ground locations?
pm papawana on forum as he offers them all the time. Or if you look under the general form right now he is offering wiring diagrams. The main grounds from memory are under battery box to frame. At starter frame to engine and inside car on left pillar above fuse box but there are more
Old 04-07-2018, 02:32 PM
  #10  
Rescue Rogers
Dementer sole survivor

Support Corvetteforum!
 
Rescue Rogers's Avatar
 
Member Since: Oct 2015
Location: YUPPY HELL Westford MASS
Posts: 16,442
Received 6,290 Likes on 3,919 Posts
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Default

If your not going to pull the battery, then reach down and jumper across your solenoid and put power from the battery lug to the solenoid lug, the starter will engage adn turn the motor. If you worry about saftey and things like that you can get a cheap remote starter. If it wont turn over its the battery. I would start there before you start tracing power that you dont have. I doubt you had any fusible links blow just sitting there and your horn wouldnt work and the buzzer wouldnt work if you had. power to your car all goes to the starter, then up to the buss bar on the horn relay, then into the wring harness at the fire wall

Good luck
Old 04-07-2018, 02:44 PM
  #11  
buns
Safety Car
 
buns's Avatar
 
Member Since: Feb 2006
Posts: 4,142
Received 690 Likes on 537 Posts

Default

Wiring diagrams, '68 to '82:


https://sites.google.com/a/c3vrmail....iring-diagrams
The following users liked this post:
Jeffs82c3 (04-13-2018)
Old 04-07-2018, 03:46 PM
  #12  
tomgallucci57
Racer
 
tomgallucci57's Avatar
 
Member Since: Oct 2009
Location: cleveland Ohio
Posts: 280
Likes: 0
Received 1 Like on 1 Post
Default

the brite-light foot switch on the floor board may need replaced.i understand alot of electronics are controlled by this switch..
Old 04-07-2018, 03:51 PM
  #13  
Rescue Rogers
Dementer sole survivor

Support Corvetteforum!
 
Rescue Rogers's Avatar
 
Member Since: Oct 2015
Location: YUPPY HELL Westford MASS
Posts: 16,442
Received 6,290 Likes on 3,919 Posts
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Default

power is routed through the headlight switch for some accessories but I dont believe any go through the foot switch
Old 04-07-2018, 04:42 PM
  #14  
2mnyvets
Racer
 
2mnyvets's Avatar
 
Member Since: Jul 2015
Location: Lehigh Valley Pennsylvania
Posts: 377
Received 88 Likes on 63 Posts
Default

On my 1973, there is as terminal on the horn relay. Not sure where it is on a 69, but it provides positive to EVERYTHING. The horn relay is on the left fenderwell. Take the wires off of that terminal and with a jumper cable from the battery provide positive to each of those wires separately. If any sparks badly you may have a serious short that burned the fusible link somewhere. All but one wire should power something. This wire will be the hot wire and will come from the battery cable on the starter.

My guess is you have broken/corroded connections there. The horn relay is the first thing it powers. If the horn works, have positive to the relay and you also have a good ground to the steering column since the horn button provides a negative to the horn relay when depressed. You also have a good ground on the horn since it works.

Last edited by 2mnyvets; 04-07-2018 at 07:57 PM.
Old 04-07-2018, 09:22 PM
  #15  
Rescue Rogers
Dementer sole survivor

Support Corvetteforum!
 
Rescue Rogers's Avatar
 
Member Since: Oct 2015
Location: YUPPY HELL Westford MASS
Posts: 16,442
Received 6,290 Likes on 3,919 Posts
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Default

That is not entirely correct. The wires connected to the horn relay are connected to a buss bar on the side of the relay. The wires from there run back into the firewall and into the harness. They also run from there to the alternator. The horn actually comes back out to the relay then to the horn
Old 04-08-2018, 09:03 AM
  #16  
2mnyvets
Racer
 
2mnyvets's Avatar
 
Member Since: Jul 2015
Location: Lehigh Valley Pennsylvania
Posts: 377
Received 88 Likes on 63 Posts
Default

Originally Posted by Rescue Rogers
That is not entirely correct. The wires connected to the horn relay are connected to a buss bar on the side of the relay. The wires from there run back into the firewall and into the harness. They also run from there to the alternator. The horn actually comes back out to the relay then to the horn
You are absolutely right, but does it matter? I have a 69 and 73. The 73 is apart and easily visible. I just finished wiring that one. The 69 is together and i can't see much but I did see that it was different. After reviewing wiring diagrams I realized the 69 had a terminal block that was remote.

The description is for the 73. I edited the original post to add that after I went out to look.

The real issue is if he has a horn, he has positive somewhere and negative at two places minimum. He has negative (ground) on the steering column and ground on the front section at the horn minimum. The OP did a lot of work chasing grounds but I suspect since he has grounds in two places grounds likely are not the problem. This can be tested with a voltmeter or test light.


If the issue is on the positive side, the place to find what is going wrong is at the common terminal. I Personally would just put a positive source there and see what happens; but I didn't want him to burn the car up if he had a short so I recommended he break the wires loose and check each one separately.

I did take some liberties with the alternator wire and the starter, but I left them out for clarity. Technically wrong, but for what he is looking at it really didn't matter. What he needs to know is that the positive comes from the battery to the main post on the starter and a wire from that main post goes to this terminal block. From there it gets distributed throughout the car. Again this is my 73 but it appears the 69 is the similar.

I would suspect a partial open in the wire from the starter to the terminal block. This may not be able to be found with a volt meter. If you have a badly corroded/damaged wire it may be able to carry enough power to show voltage on a voltmeter but not to be able to power anything. (voltage on the meter will go to 0 when you put a load on the circuit). I personally would use a test light.

It is OK to tell me I am wrong and I appreciate and respect that. But it is more important to tell the OP where I am wrong and what he should do differently. That way we all learn.

thanks
Greg

Last edited by 2mnyvets; 04-08-2018 at 10:48 AM.
Old 04-08-2018, 11:42 AM
  #17  
Duane4238
Burning Brakes
 
Duane4238's Avatar
 
Member Since: Sep 2009
Location: Western New York
Posts: 1,124
Received 140 Likes on 93 Posts

Default

To the OP- Did you go and get the battery LOAD TESTED as was suggested? If not, you are wasting your time and everyone else here. We're not just talking putting a meter on the battery to see if you have 12 volts. The load test is done with the battery under a heavy load and will tell you if the battery is any good. You can have a battery that has voltage and will blow the horn, but there will not be enough power to operate other systems such as the starter. Get your battery tested or you're just wasting time!
Duane

Get notified of new replies

To Help Please!

Old 04-08-2018, 12:34 PM
  #18  
carriljc
Le Mans Master
 
carriljc's Avatar
 
Member Since: Jan 2001
Posts: 5,358
Received 879 Likes on 764 Posts

Default

Originally Posted by Duane4238
To the OP- Did you go and get the battery LOAD TESTED as was suggested? If not, you are wasting your time and everyone else here. We're not just talking putting a meter on the battery to see if you have 12 volts. The load test is done with the battery under a heavy load and will tell you if the battery is any good. You can have a battery that has voltage and will blow the horn, but there will not be enough power to operate other systems such as the starter. Get your battery tested or you're just wasting time!
Duane


.........And clean those terminal connections also. A poor connection will let lights work and other stuff but won't be able to operate the starter.
Old 04-08-2018, 04:52 PM
  #19  
Brandon Smith
Cruising
Thread Starter
 
Brandon Smith's Avatar
 
Member Since: Apr 2018
Location: Galloway Ohio
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Default

I bought a brand new battery and have had it load tested. No issues with the battery.
Old 04-08-2018, 05:00 PM
  #20  
Brandon Smith
Cruising
Thread Starter
 
Brandon Smith's Avatar
 
Member Since: Apr 2018
Location: Galloway Ohio
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Default

Took a tester today to some positive wires. I’ve got power from the starter, and the alternator. I did try the fuse panel and don’t seem to be getting anything from there. Maybe I’m not doing it right? I take the tester and touch the medal parts with fuses in it and the key on. Is there another way to test that?


Quick Reply: Help Please!



All times are GMT -4. The time now is 10:44 AM.