Check for bad, loose, corroded connections. Also: Turn on theignition switch and the headlights and heater motor and then check voltages from the fuse block, ignition switch, amp meter to the battery to find where the voltage drop happens. The problem is at or before where you see the voltage drop.
Intermittent Electrical Issue... Input greatly appreciated and needed. (1 Viewer)
- Thread starter REZARF
- Start date
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On my 69, I lost all electrical power one day and when I jiggled the wires that go the amp meter, power came back. I had loose and bad connections there. Cleaned and secured the wires and no problem now. Am not sure about your year however.
- Thread starter
- #24
Makes sense. Thanks Pin_head
Thanks @Martyt it's on my list to check and look over.
I just ordered a new fusible link from Coolerman to reinstall into the harness. Also, I ordered up some new gear to go through the battery cables and do-dads hanging off the battery. Time to clean up some wiring and sort this thing out.
On my 69, the only lights that were working were the headlights when I bought it. Took awhile to get all lights (brake lights, turn signals, hazards, back up lights, etc) working per spec. My OEM wiring was pretty much all there but the PO had buggered up some of it when he installed a trailer light set up. Most of my issues revolved around bad grounds and loose connections. Coolerman's schematics as well as the FSM really helped. Despite all that, some was trial and error--especially on the turn signals and brake lights. They say all roads lead to Rome; on the 69 anyway, much of the electrical roads lead to the turn signal cluster and the main electrical road is at the amp meter (if that is messed up, you won't have any power). Good luck and you will find the Forum threads very helpful.
mrboatman
GOLD Star
I have found that Electrical problems seem fairly simple UNTIL they are your own!! Then they are a real pain in the A$$ !! Every time a thread comes up with electrical problems I really follow them and learn a ton. @REZARF I remember reading that some had a hidden fuse in the wiring harness it might have been for the wiper/washer circuit though. I am watching and hoping you find the issue which I know you will.
JP
JP
- Thread starter
- #27
Thanks @mrboatman , my money's on the Ammeter or a faulty ground... but I am closing in on it!
- Thread starter
- #28
So after months of chasing this thing I think I found the actual problem... and created another.
Good News:
So I pulled the gauge cluster as I had eliminated nearly every possible connection except the power flow through the amp meter... I cracked the gauge cluster open and before I could disconnect the speed-o I noticed the main White 12v+ wire was loose on the terminal post... not a little loose, like the nut was visibly backed off several full turns. Snugged it up, and everything fired right up.
I took some time, cleaned up the connections and reapplied shrink wrap after the clean up. Awesome, things were looking up.
The Bad:
In my excitement to hear my 40 roar to life for the first time in 2 months I started pulling stuff apart to clean up the connections BEFORE I disconnected the battery again. I managed to let the 12v+wire from the battery to ground through the gauge cluster
I saw sparks, I saw smoke, I saw my eyes fill with tears
Anyhow, it blew the fuse for the gauges. Now the truck starts, headlights are good to go, but I have NO dash lights, fuel gauge and I keep blowing fuses as soon as I hit the ACC/ON position... burned up a couple fuses poking around and checking stuff. I realized these things weren't working once I got it all buttoned up.
I must have shorted something.
So I need to tear into it all again next time I get a chance... anything obvious I should be checking?
Two steps forward, one step back.
Good News:
So I pulled the gauge cluster as I had eliminated nearly every possible connection except the power flow through the amp meter... I cracked the gauge cluster open and before I could disconnect the speed-o I noticed the main White 12v+ wire was loose on the terminal post... not a little loose, like the nut was visibly backed off several full turns. Snugged it up, and everything fired right up.
I took some time, cleaned up the connections and reapplied shrink wrap after the clean up. Awesome, things were looking up.
The Bad:
In my excitement to hear my 40 roar to life for the first time in 2 months I started pulling stuff apart to clean up the connections BEFORE I disconnected the battery again. I managed to let the 12v+wire from the battery to ground through the gauge cluster
I must have shorted something.
So I need to tear into it all again next time I get a chance... anything obvious I should be checking?
Two steps forward, one step back.
Sorry to hear that!!
I’ve been thru similar and feel your pain.
Follow the large (10ga or 8ga) WL (White/blue) and W wires, from the alternator to the ammeter... and on to the fuse box.
The fusible link ties into the WL, from the battery+, at the PS fender apron.
It’s likely the large WL and W wires melted their insulation and shorted.
You may need to pull and unwrap your harness. But, start where the fusible link connects on the PS fender apron.
Carefully unwrap the harness, toward the firewall... see if WL and/or W are melted.
Then, start at the cluster and carefully unwrap and see if the WL and/or W are melted.
You may luck out and only need to replace WL and W.
But, if they are melted, you will need to pull the harness, unwrap it and carefully check each wire, to ensure none of the others are melted.
If you’re lucky, you may be able to tape any melted insulation, on the small wires and simply replace the large WL and W wires.
@Coolerman can help you and provide better direction.
I’ve been thru similar and feel your pain.
Follow the large (10ga or 8ga) WL (White/blue) and W wires, from the alternator to the ammeter... and on to the fuse box.
The fusible link ties into the WL, from the battery+, at the PS fender apron.
It’s likely the large WL and W wires melted their insulation and shorted.
You may need to pull and unwrap your harness. But, start where the fusible link connects on the PS fender apron.
Carefully unwrap the harness, toward the firewall... see if WL and/or W are melted.
Then, start at the cluster and carefully unwrap and see if the WL and/or W are melted.
You may luck out and only need to replace WL and W.
But, if they are melted, you will need to pull the harness, unwrap it and carefully check each wire, to ensure none of the others are melted.
If you’re lucky, you may be able to tape any melted insulation, on the small wires and simply replace the large WL and W wires.
@Coolerman can help you and provide better direction.
samatulich
SILVER Star
That sucks! My guess is wherever the sparks and smoke came from will be somewhat obivious and hopefully not too much of a PITA to fix. Were the lights ON when this happened? Maybe you just burned up the dash lights and they just need to be replaced. Is there FUEL in the tank? I know my gauge doesn’t move much when I have just a couple of gallons in the tank. What fuses are you blowing every time your key is in the ACC/ON position? Are you blowing the fuse when you’re reaching around and wiggling wires and such or when the key passes the ACC/ON when you go to start the cruiser? I’m no authority when it comes to electrical, but I have had my moments.
