Electrical Woes on 1969 FJ40 (1 Viewer)

Joined
Aug 10, 2018
Messages
396
Location
Bozeman, MT
Sounds like you might not have a good ground on that RL. If the ground is poor the bulb can illuminate a little, but not always full illumination. If the bulb doesn't fully illuminate it wont trip the flasher and you end up with the situation you're in. For me, differences in brightness are easier to see in the dark. I would see if you notice a difference in brightness between RR and RL. If there is a difference, the ground is likely the issue.
 
Joined
May 7, 2019
Messages
37
Location
Grand Rapids, MI
All lamps are full and equal bright. I did go around and sand all housings and remount. When the turn signal is engaged, the RL lamp flashes a single time at full bright, but does not flash again until arm is manipulated. That’s what led me back to the turn signal switch, along with the brake light issue. Does that make sense?

I do need to do a full cycle of cleaning all grounds and tightening bolts - this restore was never really run out before I acquired.
 
Joined
May 7, 2019
Messages
37
Location
Grand Rapids, MI
Yep, all lamps are equal - they weren’t at first, but after sanding all mounts and rewiring the front blocks seems good. Both rears are full bright on brakes and running lights, but the RL just blinks a single time on turn signal and there is play in the switch that seems to cause brake lights to stop working. I suspect the short blocks have crud or maybe mechanicals just worn out.
 
Joined
Jul 31, 2008
Messages
543
Location
Los Angeles
Time for an update! Thanks to all for the suggestions. I have resolved many of the problems I was seeing. I learned a valuable lesson - never trust PO wiring.

Some specifics:
Horn not working - turns out I must have breathed near the connector to the horn in engine compartment. Just pushed it in and now the horn works (also identified I am missing the driver side horn).

Brake lights - isolated the issue to turn signal switch. The arm is very ‘wobbly’ and after running my fingers along all bullet connectors and securing I wound up putting some pressure on the column and brake lights started working. I will pull it this weekend and have a replacement on the way.

Turn signals - FR, FL and RR all work. The RL will flash only once when arm is moved, so I traced the wiring back checking resistance and voltage out to lamp. It all seems solid, so assuming this will also be resolved by new turn signal switch. Voltage levels are also now even and lamps bright to same level. I wound up disconnecting all wiring up front from the blocks, and just doing it myself making sure that the circuits were correct per wiring diagram.

Hazards - resolved by replacing burnt out inline fuse under cowl.

On to reverse, license plate frame and interior lighting!
Well done!! It’s such a good thing to be able to go through it all and understand the system.
 
Joined
May 7, 2019
Messages
37
Location
Grand Rapids, MI
I gotta tell you, this has gone from frustrating to fun pretty quickly. Breaking down the issues and focusing on one at a time was a huge help. These vehicles aren’t modern integrated systems with central computers, they are analog and the advice to start at one component and trace your way one segment at a time is golden!
 
Joined
May 7, 2019
Messages
37
Location
Grand Rapids, MI
Makes sense. I still think it make be a ground issue. Equal brightness on the front end too?

You were right! I got under and traced wiring back from the tail light. The mid-body ground was just not... grounded. Hanging loose :/

So, got that grounded and with just the right jiggling on the turn signal arm I can get my RR turn signal. Next step is to remove and clean the turn signal switch. Does anyone have some pictures of how to get that switch out with minimal steering column disassembly?
 

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