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No Dash lights - 68 RR - Need diagnosis help

A

am3rican

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I took the dash apart trying to figure out why none of my dash lights work. Gauges work fine (except tach). Dome light works when I turn the dimmer switch full on. I also broke two pins in the dash connector. I was expecting this though. Several more pins were loose. I will solder later. All fuses checked out okay.

Questions
- How do I test if the dimmer switch is faulty?
- As you can see from the pictures, I'm missing several bulb sockets. Should there be a bulb and socket in every empty spot?
- Can someone give me a rundown on how to check the tach? I have mopar performance electric ignition. IMG_20141213_231349.jpgIMG_20141213_231359.jpg
 
Just took my gauge cluster apart and swapped out the original bulbs with LED's. The non-rallye clusters have 10 light bulb sockets on the PCB, but only need nine bulbs. In your photos with the cluster turned upside down, the open socket on the far right on the PCB is open because it's a blind hole. There are 4 lights on the top (the bottom in your pictures) for illumination; you're missing one with the blue diffuser in the background. The other two open sockets need light bulbs for the brake light and the high beam. Lastly is the light bulb for tach illumination - that one is not part of the PCB and needs it's own power source. The connecting wire is orange with a male bullet terminal on the end. You can get PCB sockets on E-bay - they measure 5/8".

While the cluster is out you might think about upgrading a few things. Replace the original voltage limiter with a digital one from Right Time Engineering. Do the ammeter by-pass. Mad Electric.com is a great site and has tutorials on how to do the swap correctly. You can swap a voltmeter in place of the ammeter. My 69 Coronet restoration thread shows some detail on how to do it and has a link to Hunt2Elk's post, which is the authority on the swap.

As for the dimmer switch, I'm not sure how to test it either, but mine was filthy and corroded so I refurbed it by cleaning all contacts along with the wire rheostat. You have to drill out the rivets with a Dremel but it's not a big deal. I was able to reuse the OEM rivets using JB Weld to secure them to the cage.
 
On the dimmer switch, 1 connection puts ground on the dome light circuit. The other 2 are the rheostat, an ohmmeter set on lowest scale should show varying resistance as the dial is rotated. X2 on the solid state voltage regulator. Your existing ammeter can be converted to a voltmeter with a small rheostat and a diode but does need to be calibrated. Perhaps the above listed postings show that. If not Auto Instruments can do it, but they ain't cheap! I have a couple of circuit boards from my 68 RR project with all pins intact. If your interested pm me. You can have 1 for the cost of shipping. Dale
PS: Having rotator cuff surgery 12/18 may be down for a few days.
 
CoronetDarter said:
Just took my gauge cluster apart and swapped out the original bulbs with LED's. The non-rallye clusters have 10 light bulb sockets on the PCB, but only need nine bulbs. In your photos with the cluster turned upside down, the open socket on the far right on the PCB is open because it's a blind hole. There are 4 lights on the top (the bottom in your pictures) for illumination; you're missing one with the blue diffuser in the background. The other two open sockets need light bulbs for the brake light and the high beam. Lastly is the light bulb for tach illumination - that one is not part of the PCB and needs it's own power source. The connecting wire is orange with a male bullet terminal on the end. You can get PCB sockets on E-bay - they measure 5/8".

While the cluster is out you might think about upgrading a few things. Replace the original voltage limiter with a digital one from Right Time Engineering. Do the ammeter by-pass. Mad Electric.com is a great site and has tutorials on how to do the swap correctly. You can swap a voltmeter in place of the ammeter. My 69 Coronet restoration thread shows some detail on how to do it and has a link to Hunt2Elk's post, which is the authority on the swap.

As for the dimmer switch, I'm not sure how to test it either, but mine was filthy and corroded so I refurbed it by cleaning all contacts along with the wire rheostat. You have to drill out the rivets with a Dremel but it's not a big deal. I was able to reuse the OEM rivets using JB Weld to secure them to the cage.
Click to expand...

Where'd you source the LED bulbs? I found the sockets on RockAuto for $3.81 plus shipping
http://www.rockauto.com/catalog/moreinfo.php?pk=443482&cc=1494759

When you say blind hole, i'm guessing it's intentionally without socket?

I'll do some reading up on the sources you gave me. How long do you think it took to replace the voltage limiter and do the ammeter to voltmeter conversion?
 
dburnett6263 said:
On the dimmer switch, 1 connection puts ground on the dome light circuit. The other 2 are the rheostat, an ohmmeter set on lowest scale should show varying resistance as the dial is rotated. X2 on the solid state voltage regulator. Your existing ammeter can be converted to a voltmeter with a small rheostat and a diode but does need to be calibrated. Perhaps the above listed postings show that. If not Auto Instruments can do it, but they ain't cheap! I have a couple of circuit boards from my 68 RR project with all pins intact. If your interested pm me. You can have 1 for the cost of shipping. Dale
PS: Having rotator cuff surgery 12/18 may be down for a few days.
Click to expand...

I just ordered the IVR4 digital voltage limiter. Figured for $60, its worth it. I never want to take the dash apart again. I'm a big guy and it was a pain in the a$$ getting the dash apart.
 
am3rican said:
Where'd you source the LED bulbs? I found the sockets on RockAuto for $3.81 plus shipping
http://www.rockauto.com/catalog/moreinfo.php?pk=443482&cc=1494759

When you say blind hole, i'm guessing it's intentionally without socket?

I'll do some reading up on the sources you gave me. How long do you think it took to replace the voltage limiter and do the ammeter to voltmeter conversion?
Click to expand...

With a blind hole I meant that there's no gauge or idiot light that needs illumination so you can leave the hole open. The sockets are all over E-bay for much less than RockAuto - just make sure you get the 5/8" not 1/2". (Guess how I know that). I used the vendor 'Deal Click' - I was very satisfied.

As for LED's, I used Hi Po Parts
http://www.hipoparts.com/categories...-Fuel-System-Parts/Pumps,-Filters-&-Plumbing/
I used them because they have a Tech Page which suggests different types and colors of LED's to use. I tend to use vendors whose websites are educational and not just a sales tool. Plus they sell needle paint.

The voltage limiter literally pulls out and plugs in - 10 secs. The conversion took me 2 - 3 hours over the course of two weekends. Looking back I don't why it took me so long, it's actually an easy swap. I think part of the reason is that I was first attempting to use the VM face over the OEM gauge, but it didn't look good. Hunt2Elk swapped the needles so that it would look OEM; I was too chicken to do that so I kept the VM needle in place and painted it orange to at least match the factory needles and called it good. BTW you can buy the VM on Summit for $20.
 
update: - ordered the Led bulbs and sockets off of eBay for $12. LEDs are white.
-Ordered the digital voltage limiter and a new tach board. Installed voltage limiter. Waiting to solder the new Board in.
- Dale (dburnett) was cool and mailed me a cluster circuit board. I cleaned it up.
- I found a guy on eBay that restores dimmer switches for $75, shipping included. Guaranteed to work. Rather dick around, I figured I'll mail it off and get one that works back.

Progress is slow. But winter is long so I'm taking my sweet time.

- Jason
 
I have everything done and ready to install but cannot seem to get the connector attached to the 10 pins out of the circuit board. Is there a trick? Don't want to break one
 
No real trick, check to make sure none of the socket (females) are bent or rolled in. Just slow and easy.
 
bah - still no lights. dimmer switch was rebuilt so i know it was good. dome light turns on but instrument lights do not...

tach is reading 4000 rpm on accesory. any idea why???
 
If you still have your incandescent bulbs, try them in place of the LED's and see if they light.
I tried LED's in my instrument cluster but went back to incandescent. LED's just didn't look right.

Your tach issue could possibly be a bad ground? have you screwed the instrument cluster back in place or is it just resting in the dash cavity? The mounting screws are the ground. Also, with electronic ignition, my rallye tach needed a circuit board upgrade. Not certain about non-rallye tach's but this could also be an issue. Was it working previously?
 
Dash lights may be same reason as stated by Lionized. Make sure the case (cluster) is chassis grounded. Also the LED's are polarity sensitive, may need to rotate the socket 90 degrees.
 
have you checked the fuse for the lights? and sometimes the clips in the fuse box corrode.
 
Lionized said:
If you still have your incandescent bulbs, try them in place of the LED's and see if they light.
I tried LED's in my instrument cluster but went back to incandescent. LED's just didn't look right.

Your tach issue could possibly be a bad ground? have you screwed the instrument cluster back in place or is it just resting in the dash cavity? The mounting screws are the ground. Also, with electronic ignition, my rallye tach needed a circuit board upgrade. Not certain about non-rallye tach's but this could also be an issue. Was it working previously?
Click to expand...

Yea the tach issue is a mind bender. I need to check continuity on the wiring. Fuse was the first thing I checked when I tried correcting the problem, but I will look again.The tach worked when I hooked it up to the battery. It has a new RT-eng tach board. It never worked since I've had It.

You nailed it on the cluster. It is not screwed in. Didn't know screws were the ground. It's a real pain in the *** to get the cluster back in. Any tricks?
 
am3rican said:
Yea the tach issue is a mind bender. I need to check continuity on the wiring. Fuse was the first thing I checked when I tried correcting the problem, but I will look again.The tach worked when I hooked it up to the battery. It has a new RT-eng tach board. It never worked since I've had It.

You nailed it on the cluster. It is not screwed in. Didn't know screws were the ground. It's a real pain in the *** to get the cluster back in. Any tricks?
Click to expand...

I've removed and replaced mine about 5 times now. This most recent removal took about 15 minutes.
Getting it back in is another story altogether. Actually, getting it in is no big deal either. Hooking everything up is the issue. I find that dropping the steering column is more of a headache than it's worth. I just go at it working from one side to the other once the cluster is in place. Usually connect tthe speedo cable right off the bat. I find it helps hold it in place until I screw it in.
 
Possibly. Screw it in and try again. Ensure that the plug on the circuit board is completely on as well.
 
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