77 FJ40 headlight

[My77FJ]

I have a 77 Toyota FJ40 that has been sitting for over 30 years. It’s a California-spec FJ40, and I’m currently working through the electrical system. I’ve managed to get just about everything working except for a couple of issues with the headlights.
The driver-side turn signal will blink once and then stop, and the headlights only seem to work on high beams. I have thoroughly inspected all the wiring to the best of my knowledge. Has anyone experienced something similar or have suggestions on where I should start troubleshooting? Any advice would be appreciated!

 

[charliemeyer007]

When turn signals only blink once its an issue the bulbs for that side. Front or real bulb is burnt out has or a ground/corrosion issue. Test the bulbs, clean the bulb sockets inside and check that it is still grounded Can also the in the switch or the blinker mechanism.

Use a jumper to test each headlight hi and low beam. The high and low beam switch can be bad.

Look at each of your plug connectors - corrosion can crawl up the wire from the crimp. Wires can break inside but look good on the outside. I just got one of those wire tracer units for cars on Amoron - haven't used it yet - but it says it can find where a wire is broken inside a harness.

I have a probe with a digital voltmeter. I have one with a light bulb. I have a volt ohm meter with continuity sound.

Coolermans Wiring Diagrams and parts

Cruiser Wiring

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Land Cruiser Factory Service Manuals (FSMs)

Factory service manuals (FSMs) for your Toyota Land Cruiser ! From the 1950s to the present!

www.cruisercult.com

 

[TXMeatball]

Turn signals: Check the hazard lights switch. Push it in and out a bunch of times to "clean" it. If it's still not working then it's a bulb or ground issue.
Headlights: Check the fuse box. Pull the fuses and clean the contacts. A lot of my electrical issues that were giving me grief ended up being this. Also sliding the fuses back and forth is a quick fix too.

 

[Grayscale]

Do the hazard lamps blink like they should?

I recall taking apart and cleaning my dimmer switch. Probably some springs in there that could get lost. Otherwise, the wiring itself is kinda vulnerable on non-relayed headlamps. You might, with care to not ground-out, test for voltage with your multimeter at the back of the lamps. The light control switch could have dirt or moisture contamination.

Almost every lamp on my truck needed attention at some point. I just replaced a brake light bulb. I made a bailing wire hook for the brake pedal so I could check them without an assistant. Every outside lamp chassis on my '75 got modified. Three extra ground wires for each chassis in these water and soil-contaminated OEM plastic boxes on the front fenders. The front lens fastening screws stripped or cracked the plastic threads, so teflon tape takes up some slack. Those wires in the lamps go to the engine bay side of the fenders. I drilled holes for screws, and squeezed in a ring terminal on the big one in the front lamps. Both chassis mounting screws have conductors for both of the rear combination lamps, which are connected to the extra ground from the red rear marker lamps, and the two license plate holder lamps. They all converge, and a single grounding wire runs to the passenger side firewall. The fenders are grounded with conductors to the firewall, which is connected with conductors to a ring terminal on the screw on the bellhousing for the timing window. Everything is cleaned, taps for female threads that hold ring terminals, steel wool on the bulbs, bits of steel wool or scotchbrite on the end of a pair of hemostats. Everything that gets dirty or corrode receives a minimal coating of dielectric grease, starting with the battery positive terminal and lug and ending at the other end of the battery.

 

[pb4ugo]

As what others said, rack the bright light switch back and forth a bunch a times, do the same for the switch. Turns signals could be a bad grounds. Light fixtures are sometimes grounded by their mounting bolts, which is problematic.

 

[My77FJ]

When turn signals only blink once its an issue the bulbs for that side. Front or real bulb is burnt out has or a ground/corrosion issue. Test the bulbs, clean the bulb sockets inside and check that it is still grounded Can also the in the switch or the blinker mechanism.

Use a jumper to test each headlight hi and low beam. The high and low beam switch can be bad.

Look at each of your plug connectors - corrosion can crawl up the wire from the crimp. Wires can break inside but look good on the outside. I just got one of those wire tracer units for cars on Amoron - haven't used it yet - but it says it can find where a wire is broken inside a harness.

I have a probe with a digital voltmeter. I have one with a light bulb. I have a volt ohm meter with continuity sound.

Coolermans Wiring Diagrams and parts

Cruiser Wiring

Free manuals downloads

Land Cruiser Factory Service Manuals (FSMs)

Factory service manuals (FSMs) for your Toyota Land Cruiser ! From the 1950s to the present!

www.cruisercult.com

I noticed my side marker is out and haven’t check front. Thanks for the diagram

 

[My77FJ]

Turn signals: Check the hazard lights switch. Push it in and out a bunch of times to "clean" it. If it's still not working then it's a bulb or ground issue.
Headlights: Check the fuse box. Pull the fuses and clean the contacts. A lot of my electrical issues that were giving me grief ended up being this. Also sliding the fuses back and forth is a quick fix too.

Will do. I know the hazards work minus the front driver blinker

 

[charliemeyer007]

There you go figure what is wrong with the driver front bulb/wire/switch

 

[bikersmurf]

Never underestimate the importance of a ground…



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