Dead..no power ???

[a69vette]

Does anyone know where I should go from here. I had the car out yesterday, drove around a few people we had over for Thanksgiving. I park the car, and went inside for a couple of hours. Now it's time to bring it into the garage. I crank it up, runs for about 8 seconds, and dies. Now I have no power. The started won't turn over, the lights won't come on, even the interior lights are out. The clock has stopped, but the horn will honk! My meter says the battery is OK, I don't even see a drop in voltage when I honk the horn. I've check all the fuses in the fuse panel, they're OK.
Now what???

Rick

 

[JohnZ]

Chances are the main power feed connection from the horn relay bus to the inside of the car has corroded/failed in the outboard bulkhead connector below the master cylinder - it's a 12-ga. red wire, and it's in the outboard half of the connector. When this terminal gets corroded, the resistance of the connection increases, which heats up the terminals, and it frequently melts the plastic around the terminals in the connector. That's why you have no power inside the car, but the horn works (it gets power from the horn relay, and has no hot circuit inside the car - just the ground for the relay at the horn button).

Remove the connector, clean all the terminals with contact cleaner and a toothbrush, coat them with dielectric grease, and re-install the connector. If the connector hasn't melted around the terminals for the red wire, you should be back in business.

 

[a69vette]

connection from the horn relay bus to the inside of the car has corroded/failed in the outboard bulkhead connector

This appears to be a solid connection. I didn't see any type of connector (looking thru 33 yrs of dirt/oil). I have power leaving the horn relay. Does this lead connect straight thru to the fuse pannel?

Thanks,
Rick

 

[vigman]

AOL WENT DEAD!

Sorry could not finish... but I hope that gave you enough to start with!



Vig!

 

[JohnZ]

This appears to be a solid connection. I didn't see any type of connector (looking thru 33 yrs of dirt/oil). I have power leaving the horn relay. Does this lead connect straight thru to the fuse pannel?

Thanks,
Rick

Yes, the screw connections on the horn relay are the main power feed - the 12-ga. wire from there goes into the outboard connector under the master cylinder, into the fuse panel inside, and feeds the ignition switch and light switch and unswitched battery-powered accessories from there (lighter, courtesy lights, etc.). This is a VERY common failure on all '63-'82 Corvettes.

 

[a69vette]

Good news, I have a complete electrical diagram. Bad, news...it's not the fuseable link. I'll be trying to work on it tomorrow. Is there a test point before the fuse panel (or is that the point were the wiring is coming thru)?

Thanks,
Rick

 

[vigman]

Give me an AIM shout in the AM

I'll pop the hood on my 73...try to talk ya in.

I would really look CLOSE at the Horn relay power coupling point.

Did the batt charger trick work as described?


Vig!

 

[a69vette]

I was not able to do any more testing yesterday. I have to do the brake job first this morning before I start on the vette (If my wife doesn't stop me for Christmas lights).

Thanks,
Rick

 

[JohnZ]

Good news, I have a complete electrical diagram. Bad, news...it's not the fuseable link. I'll be trying to work on it tomorrow. Is there a test point before the fuse panel (or is that the point were the wiring is coming thru)?

Thanks,
Rick

Nope, no test point ahead of the bulkhead connector (on the engine side) and fuse block (on the inside); if you have 12 volts at the screw connection on the horn relay (which you do if the horn works) and no power inside the car, you either have a break in the 12-ga. feed wire between the horn relay and the bulkhead connector it goes into, or a bad/corroded connection at its terminals inside the bulkhead connector. Can almost guarantee you it's inside the engine-side bulkhead connector - have seen dozens of these.

 

[vigman]

If memory serves

Isnt there a fuse hovering around the horn relay area.....?

And do you also have the firewall mounted circut breaker?

This might be for a 73 and not yours..but just trying to be thourough.


Vig!

( Try the batt charger trick.. that will tell you if it's the bulkhead connector or not.)

 

[JohnZ]

The main power feed for the inside of the car comes off the screw connection on the horn relay - it comes off the connection as a 16-ga. black fusible link, then splices to a 12-ga. red wire that goes to the bulkhead connector/fuse block. You should be able to tell by looking if the fusible link portion is fried, and you can pierce-probe the red wire beyond it to see if it has power.

The screw-connection bus on the horn relay gets its power from the large battery cable stud on the starter solenoid; that main feed wire has a ring terminal that goes over the stud, and comes off the terminal as a 12-ga. red wire, splices to a 14-ga. brown fusible link, then becomes a 10-ga. red wire to the horn relay screw connection.

If you have power at the screw connection and none inside the car, it's between the screw connection and the bulkhead connector - no fuses are involved.

 

[donhall]

If you haven't already, disconnect and clean your battery cable posts.

 

[a69vette]

Ok, an update. I have power leaving the starter, going to the regulator & alt. 1 lead from the reg. is going to a 2 post terminal (or something) mounted on the firewall above where the tach cable comes thru. The lead leaving the 2 post is Orange w/black trace(my wiring diragram does not show a Or/Bk). This is going straight into the car. I've got power on this lead under the dash, but it loops over the steering colume and I loose it. I do not have any Or/Bk going to the fuse panel. The panel is still dead.
NEXT??????

Rick

 

[vigman]

Hmmmmm

Will look @ the book again tonight... but it sounds like there is a link within the harness.

however there SHOULD be an Orange/Black on the bulkhead connector ( see previous post )

Does that Orange line go to the key switch??
( help me out ..is the key on the dash or the column?)

Can you E mail the schematic for the 69 to me

vigman@earthlink.net

My 73 is different ( slightly )

 

[a69vette]

It appears that the Orange/black lead is going to the amp meter. I guess I just don't "get it"! If it is the bulkhead connector, is this a replaceable item? I don't see where it connects unless it is a flush mount to the firewall. I don't mind doing turning wrenches, but this is NUTS!
Sorry,
Rick

 

[vigman]

The Amp meter

So you are stating....

1 lead from the reg. is going to a 2 post terminal (or something) mounted on the firewall above where the tach cable comes thru.

I believe that is an inline circut breaker you SHOULD have power on Both sides of that device.

It appears that the Orange/black lead is going to the amp meter. The AMP meter is Also a series device..measuring current across its shunt... power should be on BOTH main terminals of that too!

But in my 73 wiring the Amp meter wire colors ( on the back of the gauge) are Black & Black/White.

AND

The Feed under the dash via the bulkhead ( this gets tricky)

the line ( crkt 105 ) Is an Orange on the firewall side( engine ) and turns into a BLACK going to the Amp meter.. the return Black/White ( crkt 106 ) goes back to the firewall bulkhead and ties back to 2 points
1) The ALT on the 2 pin connector marked V
2) The Horn relay ( it ties into an orange wire first... this MIGHT be a link)

So sorry there are NO clear answers here..just info.

You can ALSO try the following... make a jump to the fuseblock, there is a male terminal marked BATT... see if that's hot... betting it's not!


Vig!

 

[a69vette]

... make a jump to the fuseblock, there is a male terminal marked BATT... see if that's hot...

It not.....but I'm getting there fast! Someone got a match?

 

[JohnZ]

The orange/black wire is the power feed for the power windows; it SHOULD originate at the screw connection on the horn relay, then it runs to a 2-post circuit breaker on the dash, then the feed wire goes through a grommet in the dash to the power window relay. That has nothing to do with your problem.

The bulkhead connector you have to get to is the engine compartment side of the fuse block that's on the inside; it's on the firewall, directly below the master cylinder, down there in the dark; it's a big black connector (actually two connectors that slide together), retained by a 7/16" hex bolt in the middle. The inboard half of the connector is the "engine harness", and the outboard half of the connector is the "forward lamp harness" - that's the connector that has the 12-ga. red main power feed wire from the horn relay in it. That wire goes through the fuse block (directly, no fuse) and direct-feeds the ignition switch, the light switch, and the wiper door override switch. When you loosen the center bolt and pull the connector off, you'll probably find the terminals for that 12-ga. power feed are corroded, and the resulting heat from the high resistance has partially melted the plastic connector around them so the terminals are loose and not making contact. See this all the time. Make sure you disconnect the battery before you disconnect anything.

 

[a69vette]

THANKS JOHN!
That's what I needed to know. I'm going after the bulkhead connector tonight.

Rick

 

[a69vette]

POWER !!!

Hold the matches!!!!! I've got power!! John I can't thank you enough. I took apart the bulkhead connector and the red lead did not look right in the connector. I pulled it out, to find out that it had actually worked it's way off of the otherside. I cleaned it up and bolted everything back together. The same lead I noticed didn't seem to seat properly, so I used the needle nose and worked it in. Hooked up the battery.....POWER!!
Hey, now I can take it out tomorrow, top down and play around (see post about "I Hate Winter" ). Maybe I'll take a cruise over to Clearwater to go see a certain someone, and their car(see post LS6)!!!
CAC! You are the best. This group makes an awesome team.
Thanks AGAIN to everyone. I'm going cruising!!!!!!

Rick