Complete Electrical power loss
- Thread starter Buffchief
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pb4ugo
SILVER Star
Did you check continuity of the fusible link. The 40 gets its power from the batt thru the white wire/fusible link. The white wire goes to the ammeter. After the ammeter the wire is white/blue. You gotta chase power starting at the batt.
Having verified all fuses and source voltage, I'd hook up the battery and with schematic in hand, start with the battery and walk through connectors in your harness to find out where you lose your 12v, "here I have it, here I don't."
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I would check for 12v to ground on the WL wire at the back of the alternator. If 0V there then it is more than likely something in the fusible link. They can look fine but the connectors can corrode. Check the connection of the WL wire at the battery also. If it was a short on the WL wire then it may have burned open a connection at a terminal crimp or splice you cannot see under sleeving or wrap.
Check for 12 volts using your positive probe (neg probe on battery ground) as you carefully probe.
You could start with the ignition off, probing the white wire with a blue stripe, which goes to your fuse block and supplies power to unswitched items like your headlights.
At some point you could turn the ignition switch on, if you dare, but that white/blue wire should lead you to the fault without needing that, as you have stated that nothing works at present, including the headlights, right?
Try not to do any arcing this time.
Not sure many like dealing with electrical issues on their 40's, but they're really pretty simple and the schematic is a great help, connections, wire color codes, etc.
Fusible link, 3 connections ??? pics ?
I would go straight to the back of starter, where does the white with blue stripe lose power ? from there it goes to ammeter or should, can you get at the back of gauges to see if you have power there ? if it's been bugered up all bets are off.
I would go straight to the back of starter, where does the white with blue stripe lose power ? from there it goes to ammeter or should, can you get at the back of gauges to see if you have power there ? if it's been bugered up all bets are off.
pb4ugo
SILVER Star
If you pull the gauge cluster, be sure the batt is disconnected.
Assuming your grounds are ok (0 ohms from battery ground to the body), that tells us that there is no power from your battery positive terminal to your fuse block via that heavy white wire with the blue stripe.
Time to roll your sleeves up and start probing to see where you lose your power along the way.
I did that on my ‘67 once. It fried the back side of the amp gauge on the instrument cluster. Was able to solder repair it.
Complete electrical power loss.
Complete electrical power loss.
One nice change for the later FJ40's, the current going to the ammeter is much less because a shunt is used (fusible link) instead of the full 30 (or 50) amps going to the instrument cluster and back again.
The ammeter on my 79 is currently disconnected and I still get full power in the system, as long as the fusible link is intact.
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Good time to pull all your plugs for cleaning and inspecting and a little anti-corrosion lube.
Congrats! Glad it worked out.
