Home page
SPONSOR AD

Support our Vendors!  |  Advertise Here

Topic: No power at ignition

in Forum: C3 Electrical


Already a Member?
Login
Not yet a Member?
Register for Free!

No power at ignition (1/9)
 1/8/16 2:17pm
BAD.S69
Former Member

Send Private Message


Vette(s):
77,79,69


Joined: 11/17/2015
Posts: 5

Help! Have gone through and changed everything from ignition switch,starter, alt, horn relay, and grounding cable from block to frame as well as negative battery cable. I don't seem to have power at the fuse panel, any suggestions where to go next? It seems to be intermittent , but right now it's just a bad 69. Thanks,b
Our Sponsors help support C3VR
Re: No power at ignition (2/9)
 1/8/16 2:24pm
vince vette
Former Member

Send Private Message


Vette(s):
1980 L82 White with doeskin interior


Joined: 1/5/2016
Posts: 72

Probably you've done this, but just in case, have you tried probing each connection on the power side of the circuits to ground? In other words, starting with the power cable coming off the battery go to the first point it connects to something else (sorry, don't have an electrical schematic in front of me) and with a volt meter put one probe on the connection and the other to something that's ground. If you have 10-14 volts there, then you know you have a good circuit that far. Just keep going like that until you find a place along the circuit where there's no potential between it and ground. Then somewhere between that point an your last good point is the issue. 

______________
As it once looked and hopefully will again
Re: No power at ignition (3/9)
 1/8/16 7:38pm
BAD.S69
Former Member

Send Private Message


Vette(s):
77,79,69


Joined: 11/17/2015
Posts: 5

Thanks, I have checked around and have 11.7volts on battery, alt, starter and horn relay. Don't seem to have juice under dash. Is there a switch or fuse I'm missing, the electrical diagrams aren't much help for me...b
Re: No power at ignition (4/9)
 1/8/16 11:56pm
vince vette
Former Member

Send Private Message


Vette(s):
1980 L82 White with doeskin interior


Joined: 1/5/2016
Posts: 72

Not sure about a '69. On an '80, power to the ignition comes from the battery side of the starter solenoid. The '80 schematic showing the hot lead to the ignition and a lot of other stuff with the label "From fusible link A at the starter solenoid". On they 80 there are two fusible links off the starter solenoid. One is "A" as I just mentioned and runs to the ignition switch. The other is "B" and runs to the light switch. You noted the horn relay has power. If like in the 80 that comes off a different power circuit, the same that powers the courtesy lights. So I suspect they work also. 

Anyway, my next shot would be to check to see if there is a fusible link on a lead coming off the starter solenoid and, if so, is it blown. 


______________
As it once looked and hopefully will again
Re: No power at ignition (5/9)
 1/9/16 1:11am
vince vette
Former Member

Send Private Message


Vette(s):
1980 L82 White with doeskin interior


Joined: 1/5/2016
Posts: 72

Was looking a little more at the 80 schematic. The lead off the starter solenoid that runs to ignition is either crimped or spliced to several leads two of which go to the ignition switch, one going to a circuit eventually getting to the horn, and one going to the voltage regulator/alternator. So on an 80 if the horn is working and there's no power at the back of the ignition switch then there would have to be a bad splice or crimp where all those wires are tied together and both wires to the back of the ignition would have to be open. Seems unlikely. Of course, the 69 could be wired differently. Assuming that it is at least wired the same in that the battery side of the starter solenoid also continues to the ignition switch, then I would just follow that wire and check everywhere it makes a connection. On the 80 there are two splices and two connectors between the starter solenoid and the ignition switch, so all possible points of failure. 

One question, when you said you had no power at the ignition switch, were you certain you measured on the battery side? 



______________
As it once looked and hopefully will again
Re: No power at ignition (6/9)
 1/9/16 7:51am
BAD.S69
Former Member

Send Private Message


Vette(s):
77,79,69


Joined: 11/17/2015
Posts: 5

Thanks, will turn on the heat and voltage meter...
Re: No power at ignition (7/9)
 1/9/16 12:46pm
Adams' AppleLifetime Member
Lifetime Member
Moderator
Send Private Message

Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas


Joined: 11/8/2003
Posts: 20129

Sounds like the problem is with the pass-thru connector at the firewall. Under the brake booster/master cylinder. This is what connects the fusebox to the engine harness. A bad/corroded connection there will kill all power going to the fusebox, and therefore anything else inside the cabin. Voltage at the horn relay proves the wiring from the battery, to the starter, and to the relay are good. You can remove the bolt/screw holding the pass-thru connector to the fusebox, and dis-connect it to have a look. Might be some corrosion, or might be some melted terminals causing the issue. Thumbs Up

______________

Joel Adams
C3VR Lifetime Member #56    

My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

Re: No power at ignition (8/9)
 1/10/16 6:28pm
BAD.S69
Former Member

Send Private Message


Vette(s):
77,79,69


Joined: 11/17/2015
Posts: 5

Thanks, will check this week...
Re: No power at ignition (9/9)
 1/10/16 10:23pm
Adams' AppleLifetime Member
Lifetime Member
Moderator
Send Private Message

Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas


Joined: 11/8/2003
Posts: 20129

 btw...if you do not have a wiring diagram, you can view and/or download them from my web page here

______________

Joel Adams
C3VR Lifetime Member #56    

My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

Our Sponsors help support C3VR