Dash Lights

[Shakey]

Exchanged the original dash bulbs with new ones. Works great except that when I reattached the lightbulb sockets into the gauge housing several of them just would light up with out twisting or turning the socket. I have all of them lighting up now, when I turn on the light switch, but if I drive over a rough road a couple of them (speedometer and tach) go out. I then need to try and twist the socket till it works, but I will have the same problem next time I drive. Are there any replacement sockets available to replace the current ones or is there any suggestion using my curent ones? Thanks.

[sblake01]

It sounds like the contacts on the circuit board are dirty.

[Arne]

On a 240Z, there is no circuit board. Those little light sockets are grounded with a small contact that touches the gauge case when the socket is snapped into the gauge. That little contact on each bulb holder is probably what needs cleaned, and it might be a good idea to clean the lip of the hole in the back of the gauge as well.

[Shakey]

Is there a replacement socket? I have tried to clean the contact points but still have problems with some.

[EScanlon]

The contact metal may need to be re-sprung so that it exerts pressure against the speedo/tach housing.

2¢

E

[sblake01]

I understsand now. We're talking about guage bulbs not dash bulbs. I have a 78 speedo in my hand right now. It must be different from a 240 speedo. This one has two wires on each socket and doesn't ground to the case. The circuit board comment was actually from my 810 which is completely different.

[Inf]

Having the exact same problem today.

Did you ever resolve this, Shakey?

It happened for me when I upgraded to the 4W bulb kit from MSA, and hadn't had problems before doing so.

I totally cleaned the contacts, and "re-sprung" them, along with sanding down to make some fresh bare metal on the lip of the housing holes. Nothing worked at all. The bulbs light up fine when I ground the contact to a bolt in the dash.

I even got desperate, sanded the back of the housing to get a nice clean patch around the holes, then bent the contact the other way, so it would be laying down against the clean back of the housing... Performed just as poorly.

Right now I am thinking that it may be due to the bulbs themselves. The older 3.4W bulbs had longer "stubs" on their sides, which may have made better contact with the end of the ground connector inside the socket.

I got fed up tonight, but later this week I'll just try throwing some of the old bulbs in there.

They clearly figured out that this "ground to the housing" method was a bad idea by the time the 280Z came around.

[zKars]

Seems to me the issue is with the new bulbs being slightly too long so that it hits the end of the green lense thingy and they do not seat completely, leaving a little tension on the base. With vibration, they come loose as they are never really tight to start with. 280's have a different and tighter socket arrangement that is much better as Steven points out, and it doesn't depend electrically on the fit.

Compare old to new for length. I remember this issue as well.

Jim

[Zs-ondabrain]

Just throwing it out there........

Make a ground wire with a 1/4" or 3/16" ring terminal on it, undo one of the wingnuts on the gauge in question, slide the ring terminal on there and replace the wing nut, tighten it up. Then ground that wire to a Well known good ground in the same area.

You can even use a length of wire without attaching it, to test my theory. Most likely a bulb issue but if the ground is bad on the gauge, this may help.

Good luck,

Dave

[Inf]

Hmm,

The sockets don't seem to have any trouble staying inside the holes.

When inserting them, before they've snapped into place, a lot of times the light will come on, but as soon as the socket is snapped into the housing, the circuit cuts out and the gauge goes dark. At first I thought it was oxidation on the inside edge of the lip on the housing, but I thoroughly scrubbed it down to get a clean contact edge, and it only seemed to make things worse.

But, I can imagine that maybe the green housing is pushing the bulb in slightly, and it's losing contact inside the socket with the grounding tab...

I really wish I could get my speedometer out - I managed to get all the cables detached, but the damn wing nuts are frozen solid. I even managed to get a pair of vise grips up there on one of the wings pretty tight, but it just slipped right off when I tried to turn it. This was for the bottom one, there's no way there is enough room to do the same on the top nut. Instead, I swapped those bulbs out doing acts of contortion under the dash to change them in-place.

It really makes me wonder why Nissan didn't just make a single plug for each gauge that has all the inputs AND power for the lights, so that you can pull it out as one unit and easily plug it back in. I feel so ridiculous plugging them in one by one as I'm sliding the tachometer back in. The lines are so short, I can barely manage.

[Zs-ondabrain]

I had the same problem with my wing nuts. So I used a 1/4" ratchet with 2) 6" extensions, a swivel (U-joint) and then I took a spare 1/2" socket and cut a 1/8" wide grove into it on both sides (looking into the socket, cut at 12 and 6 o'clock) This slips over the wingnut and allows force on both wings when trying to break it loose.

On you back, Look up into the dash, right hand holding the ratchet, left hand goes up thru the tach side and places the socket onto the wing nut. Easier said than done but it worked for my stubborn wingnuts. I had to do it blindly cause I can't fit my BIG head up past the pedals.

[Inf]

zKars, I believe you were correct.

I measured the depth of the green dome from the back of the housing and came up with approximately 0.530"

The tip of the MSA bulbs stick out of the socket by about 0.650" meaning that when they are snapped in, the bulb is pushed back into the socket against the rear spring. When pushed in, the side of the bulb base must lose contact with the grounding tab inside the socket. Bummer.

I went by the local AutoZone tonight hoping to find the Sylvania #53 bulbs that EScanlon has posted about in other threads, but no dice. Everyplace is closed now, so hopefully I can find them elsewhere later this week. Need to find some proper bulbs before I put my glove box back in for the second time this week.

Here is a picture for comparison between the 12V 4W MSA bulbs (Autopal brand) that were giving me trouble, and the old 12V 3.4W bulbs that have been in the car for years. The difference in length is about 0.2"

FWIW, these Autopal MSA bulbs are great for the sockets that don't have the green dome. The brake light, turn signal indicators, and high beam indicator are all very nice and bright. This is actually the first time in the 7 years I've owned my car that I've seen that blue high beam indicator come on. The previous owner didn't have the bulb correctly seated in the socket. Silly that it was dim for so long over something so simple.

Edit: Did some more reading, and learned that apparently the Sylvania 53 is now a 1.8W bulb. Another thread recommended the Eiko a-72, so I just ordered some online here:

http://bulbster.com/lightbulbs/eiko-a72-48002-p-3002.html

They look to be a much better fit than the Autopal bulbs.

Edit again: Bulbster.com was taking forever without telling me anything (after more than a week), so I contacted them only to be told they were out of stock and waiting for a shipment from the manufacturer. A heads up would have been nice.

Anyway, I went on google and searched for Eiko a-72, clicked the shopping option at the top, and found lots of stores selling these bulbs for a fraction of the price. I ended up buying 30 bulbs at $0.21 each from PlanetBulb (http://www.planetbulbstore.com/a-72.html)! Bulbster.com wanted $1.30 each.

Edited April 14, 2010 by Inf