79 electrical issues - The 1947 - Present Chevrolet & GMC Truck Message Board Network

bradf74 · 05-22-2011, 08:39 PM

Got a 79 that was running good. originally a six but swapped a 350 several years ago. all of the sudden I have nothing when you turn the key. headlights would not come. dead as it coupld be. battery tested at 12 volts. I jiggled wires and checked all connections. I waited a few minutes and tried again. This time I had headlights and it did crank. Pullled it under the shed and killed it and cranked it 5-6 times. Went back about 1 hour later and dead again. Battery still shows 12 volts, but no lights, nothing at the key. I checked the ground to the battery and it is still tight to the motor and Battery terminal.

What to look for next?

**old Rusty C10** · 05-22-2011, 09:26 PM

check all your connections starter fusible link etc..also make sure that your ignition switch is good

bradf74 · 05-22-2011, 10:04 PM

checked the starter and alternator. There is s junction block on the firewall with 2 wires coming in from the right (if you are facing it) and nothing on the left post of the junction block. Is that normal?

How do you check the key switch without tearing the column apart?

Also where are the fusible links?

bradf74 · 05-23-2011, 06:25 PM

ok update.

I have 12 volts to the alternator, junction block on the firewall, and the fuse block in the cab.

Lights still will not come on and entire interior is dead. turning the key is dead. Am I looking at the ignition switch?

05-22-2011, 08:39 PM	#1
bradf74 Registered User Join Date: Aug 2008 Location: Summit, MS Posts: 56	79 electrical issues Got a 79 that was running good. originally a six but swapped a 350 several years ago. all of the sudden I have nothing when you turn the key. headlights would not come. dead as it coupld be. battery tested at 12 volts. I jiggled wires and checked all connections. I waited a few minutes and tried again. This time I had headlights and it did crank. Pullled it under the shed and killed it and cranked it 5-6 times. Went back about 1 hour later and dead again. Battery still shows 12 volts, but no lights, nothing at the key. I checked the ground to the battery and it is still tight to the motor and Battery terminal. What to look for next?

05-22-2011, 09:26 PM	#2
old Rusty C10 Robert Olson Transport Join Date: Oct 2002 Location: recent transplant to NC USA Posts: 20,345	Re: 79 electrical issues check all your connections starter fusible link etc..also make sure that your ignition switch is good __________________ Bob 1951 International running on a squarebody chassis "If a man's worth is judged by the people he associates himself with, then i am the richest man in the world knowing some of the fine people of this board" http://67-72chevytrucks.com/vboard/a...t.php?f=25&a=9 (you can review the site rules here!) PM Me for your vehicle/parts hauling needs in the North East US or see my Facebook page Robert Olson Transport Live each day to the fullest.. you never know when fate is going to pull the rug out from under you... I hate cancer!!

05-22-2011, 10:04 PM	#3
bradf74 Registered User Join Date: Aug 2008 Location: Summit, MS Posts: 56	Re: 79 electrical issues checked the starter and alternator. There is s junction block on the firewall with 2 wires coming in from the right (if you are facing it) and nothing on the left post of the junction block. Is that normal? How do you check the key switch without tearing the column apart? Also where are the fusible links? Last edited by bradf74; 05-22-2011 at 10:07 PM. Reason: forget something

05-23-2011, 06:25 PM	#4
bradf74 Registered User Join Date: Aug 2008 Location: Summit, MS Posts: 56	Re: 79 electrical issues ok update. I have 12 volts to the alternator, junction block on the firewall, and the fuse block in the cab. Lights still will not come on and entire interior is dead. turning the key is dead. Am I looking at the ignition switch?



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