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Soldering Required to Replace Instrument Panel Bulb

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tekochip
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Not a good decision
tekochip   4/15/2014 8:36:55 AM
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I worked on a project where the decision was made to solder a bulb in place.  The sentiment was that the bulb was a super high reliability bulb rated for high vibration and an outrageous number of hours.  I was against it because if the bulb failed you knew full well that somebody was going to run down to Radio Shack and buy the first bulb that fit into the board, and it wouldn't be the best bulb.  Most units made it through the normal life span, however the unit was used outdoors and some units failed when the leads corroded off the bulbs.
 
Good incandescent bulbs are getting harder to find and the prices are going up.  Coin operated games used to use mountains of them, but now the game manufacturers are looking for alternatives.


TJ McDermott
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Re: Not a good decision
TJ McDermott   5/8/2014 2:20:07 AM
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What does it mean when half the bulbs in the instrument cluster fail over a period of 12 months in a car 8 years old?

Is it that bulb life was reached and they're actually pretty consistent in their length of service?

Or does it mean there's something wrong in the electrical system that puts surges into the lamps?

Ockham
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Gold
Re: Not a good decision
Ockham   5/8/2014 3:32:08 PM
One thing that it may mean (when bulbs start blowing) is that the voltage regulator in your automobile's alternator has gone bad.

Incandescent filaments which are subjected to over-voltages can and do fail with distressing frequency. When an electronic or mechanical regulator fails and your alternator zaps your electrical system with 16 or 18 volts, it is not unusual to see the filaments fail...even when other electrical things don't. Filaments are defenseless against overvoltages.

Check your alternator and grounds.

 

Amclaussen
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Re: Not a good decision
Amclaussen   5/8/2014 5:44:54 PM
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Some sytems display a strong temperature dependence: the one in my old 1991 Spirit R/T allows voltage to climb above 16 volts on really cold days! I found out that my modification to add headlight relays started to blow the halogen H4 bulbs frequently as the regulated alternator raised the voltage as the temperature went freezing cold.

William K.
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Re: Not a good decision
William K.   5/9/2014 11:07:56 AM
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Amclussen, The alternator output does need to rise as the temperature drops becaause the voltage to push a charge into a lead-acid battery rises as the temperature drops. But sometimes the clibration of the voltage regulator is a bit off, and a high ground resistance in the regulator circuit will also raise the alternator output voltage. A check of the battery voltage with the engine running will reveal a calibrationproblem but not a problem of excess resistance between the alternator output and the battery terminals. That check requires measuring the voltage between the alternator positive output terminal and the battery positive terminal, and then checking the voltage between the alternator negative and the battery negative. The total drop should be far less than one volt.

Amclaussen
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Re: Not a resistance problem.
Amclaussen   6/18/2014 1:02:18 PM
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Hi William K., it was not a high resistance problem. I've checked all ground and positive connections and found the alternator-regulator simply puts out too much voltage! (above 16 volts at freezing ambient temperatures only). As voltage drops are now negligible, my car is prone to blow bulbs in those conditions. It was an unexpected consequence of replacing and improving the headlamp wiring with Heavy Duty Relays and heavier wiring.  At least now I can see better at night when my headlamp bulbs are still functioning! Amclaussen.

William K.
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Re: Not a resistance problem.
William K.   6/18/2014 11:53:45 PM
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Amclaussen, then the one remaining option would be to try a different regulator. The only time that I had a similar failure I did have to replace the solid-state voltage regulator, which for that car cost about $17. That was for a 1978 Plymouth. That regulator was a separate module, with two connections and it was simple to replace. If the regulator is built into the alternator it will be more expensive, and if it is built into the"engine control module" it may be horribly expensive. There are methods available to lower the voltage to the lights, but most of them require a bit of technical skil to implement them reliably. A high-current rated power diode in series with the headlamp feed line would drop about 0.7 volts, or two diodes in series would drop 1.4 volts, which might be enough to extend the lamp life a bit.

If you can gain the attention of the car-makers repairs expert, that person may be able to describe the cause of the problem as well as the cure. I have done that a couple of times.

William K.
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Platinum
Re: Not a resistance problem.
William K.   6/18/2014 11:53:48 PM
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Amclaussen, then the one remaining option would be to try a different regulator. The only time that I had a similar failure I did have to replace the solid-state voltage regulator, which for that car cost about $17. That was for a 1978 Plymouth. That regulator was a separate module, with two connections and it was simple to replace. If the regulator is built into the alternator it will be more expensive, and if it is built into the"engine control module" it may be horribly expensive. There are methods available to lower the voltage to the lights, but most of them require a bit of technical skil to implement them reliably. A high-current rated power diode in series with the headlamp feed line would drop about 0.7 volts, or two diodes in series would drop 1.4 volts, which might be enough to extend the lamp life a bit.

If you can gain the attention of the car-makers repairs expert, that person may be able to describe the cause of the problem as well as the cure. I have done that a couple of times.

Amclaussen
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Platinum
Re: Not a resistance problem.
Amclaussen   6/19/2014 2:09:33 PM
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Unfortunately, This car has the regulator embedded into the engine control module... One possible solution is to install a voltage regulator for the headlamps and other bulbs, but as the currents are not small, it would be costly.  Another one is to allow some resistance to be switched-in when the voltage is going too high, like on cold days.  But it is not really a problem on 98% of the days of the year here, so I will leave it as it is for now.

William K.
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Platinum
Re: Not a resistance problem. One other option
William K.   6/20/2014 9:29:48 PM
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One other option would be to diconnect the regulator that is part of the engine control module and replace it with a separate regulator module. The replacement could be either a commercial unit or a custom design, either would be simpler and cheaper to service or replace than that ECM, which is undoubtedly very expensive and probably hard to obtain. Alternator regulators are not that very hard to design, since they don't need to have microsecond response times. Fast regulators are always more work to design and to make function correctly.

bob from maine
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Platinum
Re: Not a good decision
bob from maine   5/8/2014 3:56:58 PM
TJ: I've had customers with this complaint - incandescent bulbs are sensitive to over-voltage and cars that burned-out headlights, dome lights, brake light bulbs frequently would trace back to a faulty voltage regulator or a loose ground allowing the alternator voltage to rise to above 15V. Now most alternators have built-in regulators but in the bad-old-days the regulator was mounted on a fender somewhere and often the wires would get pulled out or corrode. I had a Volvo 144 that would burn-out the left front headlight every 6 months. The reason turned out to be the hood was vibrating at speed and this vibration was transferred down to the headlight bulb and breaking the fillament. It turns out it was a common Volvo 140 series problem and was cured by adjusting the hood stand-offs. Some service techs knew this, but because of the way the dealer shop worked, the word never got to the other techs until the service writer did a "hurry-up" replacement himself and the tech told him about it.

William K.
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Platinum
Why are the bulbs soldered in?
William K.   4/15/2014 10:14:25 AM
Soldered in and hard to replace incandescent bulbs are a pain, no doubt. But the improvement in assembly reliability by avoiding a socket is real, and the price of a baseless wire-lead bulb is a bit less, so they get soldered in. And most of them last a long time.

One large item that stands in the way of using LED illumination is color variability in white LEDs. Most incandescent lights are all the same color and dim in a similar manner, while white LED devices have quite a spread. That is one driver behind the intensly colored displays that do use LEDs. Stylists and other picky people demand that all of the light sources on an instrument cluster match colors, and that increases the costs of the LEDs quite a bit. Advances in production are reducing the cost, and brighter devices reduce the number that are needed, but it is a more recent change. That is why there are soldered in bulbs.

J. Williams
User Rank
Platinum
Re: Why are the bulbs soldered in?
J. Williams   6/17/2014 6:12:18 PM
Most people dump their cars before they reach ten years old so the bulb issue usually isn't problem.  However, the back lights for the manual HVAC controls on my '02 Suburban are soldered into the PWB that holds the fan/temperature/zone controls plus the push button switches for fresh/recirc, AC, rear defrost, etc.  Mine have burnt out.  Truck has 209K miles and things do wear out, but the prospect of buying a new control unit for who-knows-what at the local dealer or somewhat less from an on-line OEM parts house is not attractive to me.  Nothing else wrong with the panel, just the lights.  That kind of annoyance definitely sours my impression when something is made to be non-repairable for something as minor as a bulb.   

Amazon sells an AC Delco replacement for about $125 and I imagine the dealer price is probably $300 or more.

Being an engineer, I'll just solder in new bulbs (if I can find an equivalent grain of wheat bulb) or replace them with an LED with a dropping resistor.  I know the dimming won't be consistent with the other bulbs, but I rarely use the dimming feature anyways.  

Nancy Golden
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Platinum
Not Just Soldering - Getting To It
Nancy Golden   4/16/2014 6:35:08 PM
And even more surprisingly is the extent you have to go through just to get to the bulbs:

"Not only that, but you have to remove all the needles from the gauges to disassemble the instrument panel enough to get to the bulbs."

What a nightmare for replacing a part that is known to have a finite life and may fail.

Cabe Atwell
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Blogger
Re: Not Just Soldering - Getting To It
Cabe Atwell   4/24/2014 2:38:47 PM
No doubt the manufacturer designed the speedometer to rip people off when a simple bulb replacement is all that's needed. You should just 'roll' the miles back on the speedometer and sell the vehicle back to them at a much higher cost.

HarryB
User Rank
Gold
Maybe yes maybe no...
HarryB   5/8/2014 3:24:16 PM
As has been pointed out, the soldered connection could be more reliable than a socketed bulb (vibration, corrosion etc.) It may be that the bulb costs .$25 cents and a  socket raises the price to $2.50.  I too am sad that products are not built to last but we have our own capitalistic greed to blame for that... who would build you a 25 year life span product when they can sell you a new one in five... It's also getting to the point where another engineer is the only one clever enough to fix a failed product.

tomintx
User Rank
Silver
Same thing on old stereo gear
tomintx   5/8/2014 4:21:14 PM
I have this weakness for 70's era mid-high end stereo gear (no tubes, I'm not insane).  I have an FM tuner which has these nice little Left/right bulbs which help the user to tune right to the center of the frequency.  Of course they long ago burned out.  I managed to replace them with LED bulbs in the right colors, and it actually works pretty well.

 

 

Amclaussen
User Rank
Platinum
Re: Same thing on old stereo gear
Amclaussen   5/9/2014 11:52:57 AM
tomintx: I wouldn't say you have a weakness...  HiFi equipment from the 70's is frequently known for its excellent performance and outstanding assembly quality, that was available in those great years. After the 80's, manufacturers of HiFi and Stereo gear started to fall into the nebulous, "exotic" or even "esoteric" class of equipment that was frequently promoted on false premises(akin to Black magic!).  With the popularity of personal computers, video games and other hobbies, people's interest in genuine High fidelity started to be lost, and things never returned to those golden days.  Even when many examples of better and better equipment have been produced on the last 20 years, many fine examples of perfectly good (and extraordinary) equipment persist today. Actually, many of today's FM Tuners are well BELOW the performance of older tuners. Probably the only performance aspect that tends to be better today is stability, but everything else was better in the 70's (I remember having installed and aligned many tuners on those days, and had the pleasure of listening to good FM stations through what was probably the very best example in FM tuners of all time; the Sequerra Model 1, very expensive but exquisitely hand made!. (http://www.google.com.mx/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=5&cad=rja&uact=8&ved=0CDQQFjAE&url=http%3A%2F%2Fhometheaterreview.com%2Fsequerra-model-1-fm-tuner-reviewed%2F&ei=mvlsU8a1Esup8QHOkIGoBA&usg=AFQjCNHEc5crmoq5N-NV0h2pu22i4uqSFQ&bvm=bv.66330100,d.b2U)

Battar
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Platinum
Re: Same thing on old stereo gear
Battar   5/12/2014 1:36:40 AM
Amclaussen,

                  There is still a small but growing market for "retro" hifi equipment with 70's look, sound and quality, notably in products by Tivoli, Tangent and Sangean. But for quality you have to pay, and you can understand why a generation growing up listening to Eminem and his ilk, and expecting recorded music to be a free service, are not particularly interested.

Mr. Wirtel
User Rank
Gold
Re: Same thing on old stereo gear
Mr. Wirtel   5/9/2014 9:43:56 PM
  I too use stereo gear from the 70's for the simple reason that they have yet to wear out. Except for turntables and changers. Them I buy at garage  and estate sales. When the motors wear out or the belts start slipping, I pirate the stylii and/or cartridges to recycle in another unit down the line. The most obvious difference I find is how much better the old stuff can pickup and broadcast AM radio. That is very important in St. Louis if you expect to hear Cardinal baseball or Blues hockey. At home I still listen primarily to vinyl, much of which is 40+ years old.

oldjimh
User Rank
Silver
dont get mad, get even
oldjimh   5/8/2014 4:49:21 PM
That the issue has created a 'cottage industy' as an earlier poster noted tells me it's not an uncommon failure for this line of vehicles. Surely it was a manufacturing decision to save a step,  perhaps manual insertion of the lamp.   Chances are the panel itself is subcontracted.

When i get really mad  i go to the manufacturer's website and click on "investor relations".  Then i find the CEO and write him a personal, handwritten note explaining he has a problem with either his design or procurement department  which if unchecked will destroy his repeat customer business.


A sample  panel from a junkyard would really make the point.

But to an immediate preventive action  - incandescent lamp life is inversely  proportion to about 12th power of applied voltage.   Running your instrument lamps just a little below  full brightness will extend their life for years. 

MIROX
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Platinum
Vehicles are not engineered or designed for "forever" service
MIROX   5/8/2014 8:34:11 PM
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The originator of the post failed to specify simple data like Model Year, and mileage!

After all in Auto Industry not a single vehicle is designed to last "forever" and 82% of NEW Vehicle buyers get a replacement every 3 to 5 years.

No vehicle is ever made and no Company would financially survive to cater to the 5% of New Vehicle purchasers who intend to keep it "forever" but in reality only 1.8% do, that is 288,000 vehicles annually out of 16 million or more that end up to be "forever" cars with just one owner.

If every part would be over-designed and every system backed up with multiple redundancy the cars would not cost $20,000, but several times that amount.

TunaFish#5
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Gold
Re: Vehicles are not engineered or designed for "forever" service
TunaFish#5   5/9/2014 6:52:47 AM
@Mirox,

Thanks for the insider's view.  Everything you say certainly makes sense.  of course, "Nothing's designed to last forever." Of all places on the internet, I think user's of this site would be the first to agree with that point.

However,
  1. I think oldjimh's comment makes even more sense.  (i.e. presence of a cottage industry, etc.)
  2. The philosophies you've expounded ignore the entire issue of the vehicle resale/resuse market.   That vehicle buyers get a replacement every 3 to 5 years is a myopic, product-volume-centric assessment.
  3. I think its a bit of a stretch to take the conversation from soldering a screwed-in "consumable" part to discussing "over-designed and every system backed up with multiple redundancy."

And, consider this:  if this sort of issue occurred in a government contracted item & got publicized, it would go down in the annals of infamous engineering history with the [ $300 - $2000* ] toilet seat and hammer.

* - I don't recall what their prices were, and I'm not going to research it.

In fact, Jeff's story is a Double-Monkey Winner:
  1. Story #1:  removing all the needles in a guageboard to replace a single lightbulb
  2. Story #2:  soldering in a screw-in consumable item

(in my background, a consumable part is one that's expected to need replacement before too long.)

I submit that the better answer is something along these lines:

In the corporate decision process:  The objective of maximizing product volume wins over the objective of establishing the brand as a reliable, well-designed product.

ndjalva
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Iron
required deletion
ndjalva   5/9/2014 11:43:45 PM
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The ony way to reduce excess worthless inventory is to make the junk pile smaller and sell more useless junk.

ndjalva
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Iron
required deletion
ndjalva   5/9/2014 11:43:45 PM
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The ony way to reduce excess worthless inventory is to make the junk pile smaller and sell more useless junk.

Battar
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Platinum
The extra buck
Battar   5/12/2014 1:39:52 AM
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Jeff says, "I would have paid the extra buck...to save trouble"

The design team at the factory ask, "you and who else?" which is a legitimate question, and they know the answer.

Cadman-LT
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Platinum
The Way Things Are
Cadman-LT   5/13/2014 5:13:53 PM
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They don't want you to fix your own stuff. They want you to come in and pay them tons of money.

Cadman-LT
User Rank
Platinum
Re: The Way Things Are
Cadman-LT   5/13/2014 5:15:48 PM
It isn't like it used to be. Cars were simple, fix everything yourself. It's all about money now. Make stuff so it breaks...it's disgusting.

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