That'd be where I'd start . . .
Help! I have a electrical problem.
Thread Starter
Instructor
Joined: Jan 2008
Posts: 213
Likes: 20
From: Littleton Colorado
Help! I have a electrical problem.
Last night while drving home the problem happened 4 times. While I was drving the car on the highway everything cut off, engine, lights for about 1 second than came back on and drove fine untill it happened again. The drive lasted about 45 min. The last time it happened I was in the driveway and I hit the highbeam switch, the car died and I had to push it into the garage. I checked for power at the battery, good, starter, good, Alt, good and at the point were the wires plug into the firewall, good. No powe in the int of the car. Could there be a problem with the dimmer switch? On the drive home there were bumps in the road and it didn't do anything when I hit one of them. Thanks for your comments. John
Le Mans Master
Joined: Jun 2004
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From: Southeast Missouri
Thread Starter
Instructor
Joined: Jan 2008
Posts: 213
Likes: 20
From: Littleton Colorado
I checked power to the firewall plug. Power in the engine compartment. I don't see any power at the fuse pannel. I did see the clock second hand moving, but when I opened the door it stoped. I would than check power to the alt and I would than see the clock moving, again open the door it stoped. I placed a battery charger on the car and it didn't make a difference. I'm going to pull the ingition switch and check it now. John
Burning Brakes
Joined: Aug 2001
Posts: 1,104
Likes: 1
From: Frederick Md
This car have a seperate small cable made into the positive bat cable like a lot of early GM cars, powers nearly everything. Could be that baby.
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Le Mans Master
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Headlights, interior lights, etc are powered regardless of the ignition switch. I think your problem is at the bulk head firewall plug. It could be intermittent, and or bad enough that when you load it up it heats up, and caused current drops and or fluctuations.
I would pull that, clean and inspect it. Make sure the plug pins are making contact and making a good contact. Make sure the pins are not wobbly or broken. There is a lot of current running through that bobby pin size connector.
Next, I would check and clean every ground cable and strap. Buy new screws or bolts if the old ones are rusty. If the straps are corroded buy new ones. Cleaning them removes the protective anodizing and it will be corroded again in a year or so. Clean the grounding points and use dielectric grease when you re-attach them.
Mark
I would pull that, clean and inspect it. Make sure the plug pins are making contact and making a good contact. Make sure the pins are not wobbly or broken. There is a lot of current running through that bobby pin size connector.
Next, I would check and clean every ground cable and strap. Buy new screws or bolts if the old ones are rusty. If the straps are corroded buy new ones. Cleaning them removes the protective anodizing and it will be corroded again in a year or so. Clean the grounding points and use dielectric grease when you re-attach them.
Mark
Race Director
Joined: Feb 2007
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From: northern california
C2 of Year Finalist (track prepared) 2019
One thing you want to check especially well is that the locking tabs on each connector really are locked. Both connectors have two tabs and if only tab is locked, the connector can pull away sufficiently to break the connection to several circuits. (How do I know? See paragraph #1)
Good luck,
Jim
Instructor
Joined: Dec 2006
Posts: 178
Likes: 4
From: East Bay CA
Not sure by your description when the car died did you have to restart it or not. I have a 67 small block coupe and the engine would cut out while driving. Long story short but the ignition switch had gone bad and once I replaced it everything was fine (still is too!)
Good luck.
Good luck.
Team Owner
Joined: Oct 2000
Posts: 38,897
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From: Washington Michigan
It's the mating terminals for the big red wire on the inboard multiple connector on the engine compartment side of the fuse block, commonly known as the "red wire syndrome". Pull the connector off, and you'll find the terminals corroded, and the terminal cavity heat-distorted. That's why you had power in the engine compartment and no power inside the car - very common midyear problem. 
Thread Starter
Instructor
Joined: Jan 2008
Posts: 213
Likes: 20
From: Littleton Colorado
It's the mating terminals for the big red wire on the inboard multiple connector on the engine compartment side of the fuse block, commonly known as the "red wire syndrome". Pull the connector off, and you'll find the terminals corroded, and the terminal cavity heat-distorted. That's why you had power in the engine compartment and no power inside the car - very common midyear problem.
Thread Starter
Instructor
Joined: Jan 2008
Posts: 213
Likes: 20
From: Littleton Colorado
It's the mating terminals for the big red wire on the inboard multiple connector on the engine compartment side of the fuse block, commonly known as the "red wire syndrome". Pull the connector off, and you'll find the terminals corroded, and the terminal cavity heat-distorted. That's why you had power in the engine compartment and no power inside the car - very common midyear problem.
Team Owner
Joined: Oct 2000
Posts: 38,897
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From: Washington Michigan
John, I pulled the connectors off and the terminals don't look corroded or heat distorted. There was a little bluish green on the inboard connector on the two bottom left terminals on the fuse block side. I used a small wire brush and cleaned them up. The top large red one looks good. I placed them back togather and still no power inside except horn blows and clock works but when you open the door the clock stops. Horn still works. Tomarrow I'm going to pull the battery and have it checked. With my small meter it shows 14 volts at the battery and all the ways up to the plug into the firewall. Nothing inside.
Thread Starter
Instructor
Joined: Jan 2008
Posts: 213
Likes: 20
From: Littleton Colorado
OK, if you have power outside but none inside, and the terminals in the multiple connectors look good, it has to be an open circuit inside the fuse block or a bad ignition switch; if you don't see power on the 12-ga. red wire terminal on the back of the ignition switch, the open circuit is in the fuse block. Do the headlights, taillights, or brake lights work?
Last edited by John 66 Vette; Sep 10, 2008 at 07:16 PM.
Team Owner
Joined: Oct 2000
Posts: 38,897
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From: Washington Michigan
It's not the battery.
The clock, glove box light, courtesy lights, and brake lights are all fed by one circuit from the same fuse at the bottom of the fuse block; if the clock works, the fuse is OK, but I don't know why you lose power to the ignition switch and the clock when you open the door - that just grounds the courtesy light circuit to turn on the courtesy lights, and the fuse would blow if that circuit was shorted.
Do you have power windows?
The clock, glove box light, courtesy lights, and brake lights are all fed by one circuit from the same fuse at the bottom of the fuse block; if the clock works, the fuse is OK, but I don't know why you lose power to the ignition switch and the clock when you open the door - that just grounds the courtesy light circuit to turn on the courtesy lights, and the fuse would blow if that circuit was shorted.
Do you have power windows?