Printed Circuit Board Question

[ShortCST]

If I'm changing the bulbs in the dark spots on my instrument panel, and nothing is happening, does that mean that l for sure need to replace the printed circuit board?

[ShortCST]

Nobody? I just don't want to waste the $60 on a new printed circuit board if there's another common problem that's causing the dark spots.

[Killer Bee]

try swapping some of the known good lamp/lamp holders around for a quick test, those mini bulbs can be finicky in those holders..

may need new lamp holders and or contact cleaning.. pocket screwdriver or similar tool with paper towel and contact cleaner may help..

can test the assemblies outside the dash with some test leads to a battery..

possibly need to take the cluster out to inspect/clean ribbon as necessary.. be gentle, plastic is fragile.. q-tip swabs and contact cleaner may do it..

be careful to keep the cleaner on the copper only as much as possible and apply light pressure..

crc and wd-40 electrical contact cleaners have worked well for me in other similar applications..

good luck!

btw, where ya at in OC?

[ShortCST]

Thanks for all of those tips! I guess I can find contact cleaner at Radio Shack?

I'm out in Corona now.

[hamjet]

If they're regular bulbs try what killer bee suggests, if switching to the LED bulbs, try turning the bulbs 180 degrees. the ones I put in only light one way.

[81turbota]

Check known good bulb holders first. Auto parts stores will carry the contact cleaner. A light scrubbing with scotch brite on the contacts will help too to remove oxidation. You can check continuity on your printed circuit with a meter.



LED's like Hamjet mentioned are a worthwhile upgrade but they're polarity sensitive so flip them around if they don't light up. I did mine for $10.

[MARKDTN]

You can try to test the hot side of the PC Board at the bulb locations with a test light and see if you are getting power. Then test the ground side of each bulb. Then you would know where to chase the problem. Is the current PC board de-laminating?

[HO455]

Just went through the same issue with my brand new circuit board. I had to burnish the contacts on the old bulb holders and some needed a slight tweaking of the contacts. I had to careful with the tweaking as the new circuit boards are so thin I was worried about damaging it with too much pressure.

[snipescastle2]

A small piece of red scotch brite will clean up the circuit board traces very nicely!
Ben

[Killer Bee]

Originally Posted by ShortCST

Thanks for all of those tips! I guess I can find contact cleaner at Radio Shack?

I'm out in Corona now.

yep, big county, lol.. a little far for me but if you get stuck, my garage is open just about every weekend..

lots of good tips added in, you should be in good shape after checking all of those things..

radio shack may be more difficult to find than the contact cleaner, lol..

as mentioned above, local auto parts house or home depot will have what you need..

Home Depot carries both of these;
http://www.homedepot.com/p/CRC-QD-11...30-6/202262505
http://www.homedepot.com/p/CRC-11-oz...5103/205021975


product info QD® CONTACT CLEANER, 11 WT OZSKU02130

DESCRIPTION:
Suitable for cleaning sensitive electronics and electrical equipment. Evaporates quickly, leaves no residue and is safe to use on all plastics. Use where lower flashpoint cleaners are acceptable. NSF K2 Registered.
APPLICATIONS:
Telephones, PCs, relays, edge connectors, tape heads, busbars, circuits, contacts, printed circuit boards, switches & breakers.

while we're on the subject, this type of product is useful for locations where you may not be able to apply direct contact..

they both serve pretty much the same function, just need to be sure components in incidental contact won't be harmed..

read the application guides and warnings and you should be good to go for trouble free electrical connections

product info QD® ELECTRONIC CLEANER, 11 WT OZSKU05103

DESCRIPTION:
A petroleum distillate / alcohol based precision cleaner designed as an alternative to CFC based cleaners. Ideal for apps where lower flashpoint materials can be tolerated. Cost effective, plastic safe & residue free.
APPLICATIONS:
Circuit breakers, circuits, coin mechanisms, computer components, contacts, electronics, fiberglass, flux removal, sockets, lighting, plastics, nylon, plugs, relay switches, PVC, PTFE, tape heads, terminals.

[ShortCST]

I was able to find the red can. Thanks for all of the help!

I'm not sure whether or not the board is delaminatng. I guess I thought that the circuit board had to be disconnected from the back and pulled out from behind the dash for inspection. Laying on my back up in the floorboard.

[Killer Bee]

you'll want to pull the cluster to inspect/remove circuit ribbon thoroughly..

you may be able to see parts of it from underneath with light and mirror..

if you need/want to remove it, pm me for a time and I could pull it for you in a few minutes..

if you want to try it at home, I'm sure there's a how-to thread in here somewhere..

some tips for removing that may apply to your cluster;

disconnect battery..

headlight switch knob removes wth stem, there's a release button on top of switch body..

wiper switch knob has a flathead set screw, back off to pull knob..

remove speedo cable..

mechanical oil pressure gage tube compression nut has to be removed..

*remember not to start engine with this disconnected*

column boot clamp has to be removed and slide boot toward wheel..

remove harness connector and lamp holder with fiber optic tube to gear indicator..

not sure about all years but that should cover most of it for body style in you profile picture..

and like everything, don't force plastic parts apart, look for what's holding it back..

good luck!

[ShortCST]

Originally Posted by Killer Bee

you'll want to pull the cluster to inspect/remove circuit ribbon thoroughly..

you may be able to see parts of it from underneath with light and mirror..

if you need/want to remove it, pm me for a time and I could pull it for you in a few minutes..

if you want to try it at home, I'm sure there's a how-to thread in here somewhere..

some tips for removing that may apply to your cluster;

disconnect battery..

headlight switch knob removes wth stem, there's a release button on top of switch body..

wiper switch knob has a flathead set screw, back off to pull knob..

remove speedo cable..

mechanical oil pressure gage tube compression nut has to be removed..

*remember not to start engine with this disconnected*

column boot clamp has to be removed and slide boot toward wheel..

remove harness connector and lamp holder with fiber optic tube to gear indicator..

not sure about all years but that should cover most of it for body style in you profile picture..

and like everything, don't force plastic parts apart, look for what's holding it back..

good luck!

MASSIVE help, thank you!

[CST10]

Check the ground wire on the back. I had the same issue, added a ground wire to the back of the cluster to a solid clean metal on the firewall and presto. Lights worked again.