No highbeam indicator, 79 F40 (1 Viewer)

Cruiser804

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I finally have all my interior and exterior lights functioning properly. I have replaced all the fuses and bulbs including the gauge cluster. Rebuilt the headlight switch (the knob bulb could be brighter) cleaned the contacts for the turn signals and high beams on the column, cleaned the fuse holder. Turn signals, marker light, high beams, dimmer etc all work as expected. :cheers:

But I cannot get the high beam indicator to work. :bang: What next? I am guessing either something in the curciut board or switch is bad. Seems to me though if the high beams work in both constant and momentary position the switch is OK. True?:confused:
 
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Jul 14, 2008
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I had the same problem after doing almost all the maintenance you mentioned. When troubleshooting again I found I had installed the high beam indicator bulb in haste causing the wire contact to bend. I bent the contact to the original shape, inserted it , and it worked. Hope this helps.
 

bsevans

Focus on the Journey
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When you have the cluster out but still plugged into the harness, turn on the high beams and check for voltage with a meter next to the two traces that supply power to the high beam indicator.
 

Cruiser804

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When you have the cluster out but still plugged into the harness, turn on the high beams and check for voltage with a meter next to the two traces that supply power to the high beam indicator.
Ok, with or without the lights and high beams on I get nothing. I checked the other bulbs that do light and I am getting voltage there. Not sure if I checked exactly where you mean but I did it the same place I was getting a reading on the gauge cluster light., right next to the bulb holder.
 

Cruiser804

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Any suggestions? I assume since the high beams actually work the column switch is ok? I am not 100% sure how the indicator works. I assume when the same action that turns on the high beams also turns on the indicator and that I have a bad connection someplace between the switch and indicator?

Again, all other internal and external lights work as expected. New bulbs and fuses all the way around, all sockets cleaned and in great condition.

Ammeter is not working, not sure that is relevant but I believe this is related to the fusible link at the battery.
 
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I had a similar problem with the high beam indicator on my '79. I knew I had 12 volts going to the three prong connector on the back of the instrument panel, but I couldn't get the high beam indicator to work. Checked the bulb several times etc. Finally figured out that one of the three plug prongs that was bradded to the circuit board was no longer making contact with the trace it was attached to. I scraped a clean spot on the edge of the plug, and another spot on the trace and soldered a bridge between them. Fixed it right up. Here are some photos of the process.
IMG_20120228_190340.jpg
IMG_20120228_190401.jpg
IMG_20120228_190637.jpg
 
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Oct 31, 2003
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Signal voltage from the switch enters via the multi-pin plug position #7, red/yellow wire...best check point for diagnosis...
IMAG0450.jpg
 
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Oct 24, 2015
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Clarksville, TN 37043
 
I just came across this thread. I also have a 79 FJ40. I know this is a subjective question but how bright should the blue indicator light appear.

I thought I had a problem but after checking all of the recommendations I discovered the bulb is actually working as it should in every respect. It turns on and off as it should and dims and gets "brighter" when I adjust the instruments lights.

All bulbs in the cluster are new. The back of the cluster is pristine with no evidence of corrosion, damage or repair.

I can actually see light filter through very tiny gaps between the light sockets and the back of the cluster and all lights appear to be of equal brightness but it is almost impossible to tell the high beam indicator is on in a dark garage even with the instruments lights turned all the way up.

I'm in the final stages of a restoration and can not actually drive the FJ yet but I am testing it with a fully charged battery.

Do you think there is a problem?

Are these lights normally hard to see?

Can I safely assume the light will get brighter when the engine is running?

Just so you don't think I'm completely crazy. I never got to drive the FJ at night before I started the restoration.
 

oregon fj

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Normal. The blue or purple plastic lenses darken with age. By now, they are so dark that almost nothing gets out. I can't see my high beam indicator at all in any normal light. I can see a faint glow with the high beams on if it is completely dark.

Older Porsches also suffer from this. Their lenses are pure blue, but darken with time. I've put a high-power blue LED on my Porsche, and it is bright enough that it can be seen through the darkened lens.

My '64 FJ40 has a violet or purple lens. I don't have any purple LEDs handy, but did try a red one. Didn't help. With LEDs you need to have the same color bulb as the lens.
 
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Yes, both my '79 and my son's '76 are very difficult to see in any ambient light. In fact, here in Texas, his car failed inspection because the a-hole inspector said the indicator has to be visible in normal daytime light. I have been thinking that it might be possible to "thin out" some of the blue plastic to get more light penetration, maybe from the interior of the lens. New high beam lenses would be a nice thing to find.
 

oregon fj

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In the Porsche world, some have had limited success in using acetone (or similar) on a cotton swab to try to "clean" the inside of the lens.

The lens in my '64 is purple-ish. I tried a red LED, didn't help. I may see if I can find a blue LED to try instead. Might work better than the red did. Maybe.
 
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I just dealt with this exact issue with my '72. I replaced the stock bulb with a white led and cleaned the blue lens and for the first time I can see my high beam indicator even in daylight. It can be done. Dont be afraid to use 800 or 1000 grit sandpaper on the lens
 
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RENO NV
Here is what I did:
The cluster has to be taken apart to access the lens.
I used a Q-tip with alcohol to clean the lens inside and out. Then I used a small piece of 1000 grit sandpaper to polish the outside of the lens. The inside is just too small to do this to. No problem.
Now the lens is as clean as it is ever going to be, but it is still not translucent enough for a stock bulb to illuminate it. This is where the stronger white led bulb comes in. I switched all 3 of my cluster bulbs to leds and it made all the difference. I will try to ascertain exactly what leds I installed
20181019_090401.jpg

High beam indicator off
20181019_090354.jpg

High beam indicator on during daylight
 

S.CarolinaFZJ80

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90508DDD-DABA-4707-8877-243AADA89C18.jpeg
x2 for the white LED bulb. I got one from SuperBrightLEDs.com
Don’t remember which one but it works. No sanding required.
 
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