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521 high beams


jcard

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On top of other things I need to troubleshoot ( see carb thread) now my high beams started acting up... :-(

 

 

My high beams have always worked properly as far as I know, normal low beams on and then with a push of the signal switch on would come the 2 additional 'hi' beams.

 

This evening while I was in my driveway checking my various lamps, brakes, turn signals hi/low beams the high beams just decided they didn't want to turn off and the turn signals stopped working.

No signal light at all. I reset all switches, stopped the car ( reboot!) but still the hi beams persist.

 

Something tell me a relay somewhere is at fault, the little red hi beam indicator is lit ) but I'm not sure where it is and what I can do about it. Is it repairable/ replaceable? Also my turn signals ( relay?- I assume the little can device near the front of the underside of the dash ) flash reeeeally slooowly...

 

I realize I'm probably describing two separate problems....

 

Jerry

 

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The headlight relay on 521 is located by the battery.  It has four wires.  The wire colors are red with a yellow stripe, Red with a black stripe, Red with a white stripe, and Light Green with white.

In this picture, I wrote "lamp" on the headlight relay.

EngineCompRtSide4.jpg

 

Red with yellow comes from the light switch.

Red with black goes to low beams.

Red with white goes to high beams.

The light green wire with white goes to the steering column, and is grounded to switch to high beams.

 

Pulling the light green wire off the relay should cause the low beams to come on.  If it does, that wire is grounding somewhere besides at the turn signal switch.  If the high beams stay on, I would suspect the headlight relay.

 

If the relay is bad, you can replace it with a common Bosch cube relay.  You will need to make a jumper to tie pin 30 and pin 86 on the Bosch relay together.  Connect red with yellow to pin 30.  Connect Green with white to pin 85.  Connect red with black to pin 87A, Connect Red with white to pin 87.

 

You can also switch the red with black, and the red with white wire locations on the stock relay, and have permanent low beams, instead of permanent high beams.

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With the headlights on, pull the light with green wire off the headlight relay.  If the relay is bad, there will be no change, the high beams stay on.  If the wire is being grounded when it should not be, the dimmer switch is bad, or the wire has a short to ground somewhere.  You can also unplug dimmer/turn signal switch harness at the steering column.

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Well I hate to say it but whatever was causing it has stopped doing its mischief. Turn signals work and high beams switch off..

The turn signals have returned to their laid-back slow flash rate they've always had - perhaps I can buy a faster flasher unit.

 

I realize not a satisfactory diagnosis but I couldn't get it to repeat the behavior of the other evening and I'm not about to

do destructive testing....

 

Looking at the panel lights on the old girl makes me realize I'd like to do that LED panel light conversion I bookmarked on this forum; the instruments

are difficult to see at night.

 

Jerry

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The original flashers are load dependent, in that they need a minimum current flow to operate. A burned out bulb will cause the lamp to come on but not flash, or slowly. Adding a trailer with signals will cause them to flash faster. Newer flasher units, (I just grab them from cars in a wrecking yard) are electronic and flash the same speed regardless of the load.

 

If it hasn't been mentioned, soaking your fuse box in a warm mixture of vinegar/lemon juice and salt will remove any copper corrosion and make it shine like a new penny. Take a picture of your wire connections so it can be rewired correctly.

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I would suspect dirty corroded contacts.  Please start a build thread with all you triumphs and tribulations so we can better follow your truck and better h to help you. also easier for you to check if a problem returns.

 

Nice truck!

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If it hasn't been mentioned, soaking your fuse box in a warm mixture of vinegar/lemon juice and salt will remove any copper corrosion and make it shine like a new penny. Take a picture of your wire connections so it can be rewired correctly.

 

 

For this sort of thing I've used a solution that was in wide use when I worked at Varian Assoc in San Carlos( Ca) ; Ammonium Citrate- a fancy name for a solution

of ammonium hydroxide, Citric Acid and a small amount of methanol. We used it to clean the insides of high power grid tubes as it leaves no residue when baked out and it emits little noxious gases. It isn't difficult to make and works on brass, copper bronze and is safe for silver gold and platinum( what isn't?). It really does a job on fired cartridge cases.... I was a chemist there, one of two and we used it everywhere...

 

The idea is similar to the salt/vinegar solution just easier to rinse off.

 

Jerry

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  • 4 weeks later...

Well I finally found the time to look at the issue with my high beams / turn signals.

 

Long story short the plug from the switch assembly wasn't seated properly. It looked ok from a distance but it just wasted

making good electrical contact. I pulled it apart and re-seated it and away went my problems; it seems to make a proper click

or soft snap when seated correctly. This was my fault as I'd been poking around up there when I installed a secondary temp gauge.

I also replaced the signal flasher with a new mechanical and the flash is much better.

 

Now on to the heater problem and a new thread. Didn't someone suggest a 'build' thread?? Well Here goes...

 

Jerry

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