521 Signal/Flasher Assistance

[ehathaway]

Hi all, 

 

Just got my '72 521 back after having some electrical work done to it, but I'm a little stumped with the turn signals. 

 

So, the electrician told me that the signal switch is really worn out. But, the exterior turn signals turn on just fine. However, the interior arrows light up only half of the time, regardless of the exterior signals always working. I'm wondering if it could have anything to do with the flashers? Which look to be very old, and a lot of the information/stamping has faded. I can tell that they are Niles flashers, but it's pretty difficult to make out any other information.

 

Would really appreciate some advice. Happy to provide additional info!

 

Thanks!

[bilzbobaggins]

sdffs fas

Edited January 9, 2020 by bilzbobaggins
cant fix post

[bilzbobaggins]

Loose or dirty connection on the bulb holders in the cluster?  Mine do that.  I just reach up and adjust them till they start working.  No amount of cleaning the board or bulb holders has ever fully fixed it. 

 

Side note, my board patch must be failing for me on mine.  Left turn signal causes the upper left bulb that lights the cluster to be the one flashing.  LOL

[banzai510(hainz)]

what was the work done

 

YOu emergency flashers work?

usually the ball bearing part makes it loose However if the exterior lights are working then the switch must be working right?(Mr Electrician) otherwise it wouldn't work.

 

I usually rev up the motor and see if it flasher goes faster. maybe swap it with the emergency flasher , then move it back ,just in case  the connections get clean and by chance it works.

 

I had one get stuck on once. I just hit it and it went aways.

[ehathaway]

10 minutes ago, banzai510(hainz) said:

what was the work done

 

YOu emergency flashers work?

usually the ball bearing part makes it loose However if the exterior lights are working then the switch must be working right?(Mr Electrician) otherwise it wouldn't work.

 

I usually rev up the motor and see if it flasher goes faster. maybe swap it with the emergency flasher , then move it back ,just in case  the connections get clean and by chance it works.

 

I had one get stuck on once. I just hit it and it went aways.

From my understanding, some of the wiring was loose. I have a very limited knowledge of wiring, so I didn't know what to look for on my own. 

 

Yes, the emergency flashers are working. I'll try swapping the flashers, but they both seem to be different. Can plugging the wrong flasher in cause any type of issue?

[ehathaway]

38 minutes ago, bilzbobaggins said:

Loose or dirty connection on the bulb holders in the cluster?  Mine do that.  I just reach up and adjust them till they start working.  No amount of cleaning the board or bulb holders has ever fully fixed it. 

 

Side note, my board patch must be failing for me on mine.  Left turn signal causes the upper left bulb that lights the cluster to be the one flashing.  LOL

I'll give that a shot and see if it works. 

 

When the interior blinker arrow works, it's only the left one. The right one does not turn on whatsoever. 

[bilzbobaggins]

you should be able to reach both without removing anything.  Check to see if your right bulb is burnt.  I usually just twist slightly to a good clean spot.  Trying to find a pic of the back of the cluster so you know which ones to feel for.  GD photobucket is the worst std ever.

5 minutes ago, ehathaway said:

I'll give that a shot and see if it works. 

 

When the interior blinker arrow works, it's only the left one. The right one does not turn on whatsoever. 

 

[wayno]

This happens all the time to me as these trucks are getting old.

What I do if it is driving me crazy is remove the instrument cluster from the dash which requires removing the speedo cable and the plug on the cluster, this is what the back looks like.

 

Then I clean around all the holes, you can see 2 empty holes and the middle one that has a bulb holder in it in the photo below, I use rubbing alcohol and a q-tip to clean all the bulb connections, I did this on my work truck a couple years ago and everything is still working fine.

 

Your issue is not wiring, the flasher, or the turn signal lever/mechanism, as the outside signals work, it is a dirty circuit board.

Edited January 9, 2020 by wayno

[ehathaway]

1 hour ago, wayno said:

This happens all the time to me as these trucks are getting old.

What I do if it is driving me crazy is remove the instrument cluster from the dash which requires removing the speedo cable and the plug on the cluster, this is what the back looks like.

 

Then I clean around all the holes, you can see 2 empty holes and the middle one that has a bulb holder in it in the photo below, I use rubbing alcohol and a q-tip to clean all the bulb connections, I did this on my work truck a couple years ago and everything is still working fine.

 

Your issue is not wiring, the flasher, or the turn signal lever/mechanism, as the outside signals work, it is a dirty circuit board.

 

Wow, thank you for taking the time to explain. Awesome!

 

Going to give it a shot, thank you so much!

[pidge]

That’s some pretty good info. Thanks Wayno, I’ll have to store this in the brain. 

-Pidge 

[DanielC]

If the exterior lights always work, it is not the turn signal switch.   The flasher has only two connections, and power for the turn signal lights has to go through the flasher, so the flasher either works, and switches the power going through it on and off, or the flasher is either switched on all the time, or never switched on.  If the flasher is constantly switched on, when you move the turn signal lever, the turn signal stays on, until you move the turn signal back to the middle.   If the flasher never switches on, the turn signals will not come on.

 

Here is a picture of the back of the meter.  Again, if the outside turn signal lights all work, and flash, the turn signal switch is good, and so is the flasher.   The most likely cause of the indicators not working is the lamps are bad, or the lamp holder is not making contact. 

 

First thing, what do the pins hook up to.

 

I had to clean the contacts on the circuit board, the contacts in the bulb holders, the bulbs themselves. Here is a picture of one of the lamp holder holes, half cleaned. I used a Scotchbright abrasive pad to clean the contacts. In this picture, one side is cleaned, the other is not.

 

I also had to repair some grounds on the circuit board. the circuit board does not have a full copper trace for the grounds, but uses the metal case, and rivets through the circuit board to complete the grounds. To repair the grounds, I had to bridge the head of rivet to the trace on the circuit board.

 

Then I had to test the combo meter.

Get a 12 volt battery, and hook the negative up to pin 10.

Apply 12 positive to pin 1, the four dash lights should turn on.

Apply 12 positive to pin 2, the left turn light should turn on.

Apply 12 positive to pin 9, the high beam light should turn on.

Apply 12 positive to pin 12, the right turn light should turn on.

 

Apply 12 positive to pin 7, and ground pin 4, the oil light should turn on.

Apply 12 positive to pin 7, and ground pin 8, the IGN (alt) light should turn on.

 

Apply 12 positive to pin 7 and ground pin 10, and also ground pin 3, the fuel gauge should go to full.

Apply 12 positive to pin 7 and ground pin 10, and also ground pin 11, the temp gauge should go to hot.

 

Here is a wiring diagram.

 

By the way, power for the turn signals goes through the ignition switch, and the hazard switch.

 

•  

[ehathaway]

Thank you all for the support! 

 

Noticed that the signal flasher was real weak, so I replaced it last night and got a very strong pulse. But, I also noticed something quite strange that I could not see during the day.  

 

Exterior light is working great, but the interior arrow still does nothing. But at night I actually saw a very small blink of light coming from behind the cluster. I started to think that maybe the bulb was loose and hanging down, so I reached my hand behind and it still feels secure. Not quite sure what to make of it. I'm able to the see light blinking just in between the crack of the cluster and clear cover. Attached a picture to show where I'm talking about. Thoughts?

 

[Crashtd420]

56 minutes ago, ehathaway said:

Thank you all for the support! 

 

Noticed that the signal flasher was real weak, so I replaced it last night and got a very strong pulse. But, I also noticed something quite strange that I could not see during the day.  

 

Exterior light is working great, but the interior arrow still does nothing. But at night I actually saw a very small blink of light coming from behind the cluster. I started to think that maybe the bulb was loose and hanging down, so I reached my hand behind and it still feels secure. Not quite sure what to make of it. I'm able to the see light blinking just in between the crack of the cluster and clear cover. Attached a picture to show where I'm talking about. Thoughts?

 

 

Sounds exactly like what I was seeing....

I dont know how to explain it but it's sort of a back feed of power.... 

The turn signal is trying to find ground ....

 

Unfortunately you need to pull the cluster and follow the power and ground as Daniel described.... 

Edited January 10, 2020 by Crashtd420

[DanielC]

Disconnect the negative battery cable!

Remove the two screws on the bottom of the black plastic instrument cluster cover, and then the cover slides down off two clips.

Then you can see the four screws with nuts, washers, and lock washers holding the cluster in the dash.

Reach behind the instrument cluster, and VERY carefully pull the plug off the back of the instrument cluster.  It is easy to break pins off the cluster.  Remember, these are 48 year old parts.

The speedometer cable just screws on to the back of instrument cluster.

 

Then you can take the instrument cluster inside to work on it, where it is warm in the winter.