How to: Replace 95 S-Class Radio Illumination Bulbs

[simpsondb]

Over time the illumination lights in my 95 SW2 radio have been winking out. Finally, it became a Braille test at night to change settings. The orange backlight on the time/channel LCD also began flickering.

The dealer wanted no part in replacing the lights, so I decided to fix them myself. In a few hours time and with about $8 at Radio Shack, all the lights were replaced and working fine. The following steps were used to replace the bulbs in a 1995 SW2. I assume other Saturns of that era are similar.

If you’re comfortable with soldering electronics, this example may be of help. However, there’s always the possibility of damaging you’re radio, so no guarantees.

Here are the steps:

1. Removing the radio:

a. Remove the two fastener plugs, one on each side, of the radio console cowling. (push the center pin in of the fastener and pull it out. Pop the pin back out for later re-installation. Drop them in your drink cup.)

b. Pull out the cowling. Unplug the wire connector at the top. Set aside.

c. Unbolt the radio (two bolts in the top back of the radio).

d. Pull out the radio while pushing in some spring clips on the side brackets.

e. Unplug the wire and antenna connectors from the back. The radio should be free.

f. Unbolt the brackets from both sides of the radio. Put the bolts and brackets in the drink cup for re-installation.

g. Take the radio to your work table.

2. Removing the Faceplate

a. Remove the top cover from the radio.

Fig 01 Top Plate Removed.JPG

i. Remove the one screw in the back.

ii. Pry it up and off from the back and set aside. There could be some adhesive on the sides that makes this a little difficult.

b. Remove the CD or Cassette.

Fig 02 Remove CD.JPG

i. There are three or so screws holding it down. Remove them and lift the unit out slowly.

ii. Unplug its ribbon cable connectors from the main circuit board. Do not pull on the wires; use your fingernail to “work” the connector out.

iii. Remember which connectors go where.

iv. Set the unit aside.

c. Unplug the faceplate ribbon cables.

Fig 03 Top Cover and CD Removed.JPGFig 04 Faceplate Ribbon Cables.JPG

i. Like the CD/Cassette unit, work the connectors off carefully from the main circuit board.

ii. Note the holes in the chassis the ribbons pass through.

iii. note which connectors the cables go to for re-assembly.

d. Remove the knobs

(pull off the volume; pop out the Fade and Bal and remove; pull off all the little equalizer buttons.)

e. Unclip the faceplate

(Carefully work off up the spring clips from the top and sides then bottom. The side clips may not be obvious. Once free, slide the face plate unit off. Set the main chassis aside.)

3. Disassemble the faceplate

a. Lay the faceplate face down. (important)

b. Unscrew the circuit board from the faceplate.

(There are tiny torx screws, but the right flat blade jeweler screwdriver will work.)

c. Lift out the circuit board

Fig 06 Removed Faceplate Circuit Board.JPG

(Carefully lift the circuit board up or you’ll end up with lots of push buttons all over the place. Set the faceplate aside where it won’t get bumped. You’ll replace the circuit board back into it later)

Fig 05 Dissasembled.JPG

4. Replacing the bulbs
There will be a number of small 12v incandescent bulbs soldered to the circuit board. The ones on mine had blue covers (five). They at first looked like capacitors. Make a mental note of the height of the bulbs from the circuit board. The next sections cover only the bulbs on the main circuit board, not the illumination bulbs for the LCD display. See the supplemental below if you want to tackle the LCD bulbs.

a. De-solder the bulbs

Fig 07 Circuit Board w old bulbs.JPGFig 08 Faceplate Circuit Board Bottom.JPG

i. make a note where the bulbs are soldered on the back of the circuit board

ii. With a pencil soldering iron and solder vacuum, remove as much solder as possible.

iii. Work each bulb out touching its wires with the soldering iron as necessary.

iv. The circuit board bulb holes may or may not be free of solder, but it’s not necessary to get them completely open.

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A note on using the soldering iron:
- They are very hot
- They can burn your wife’s tabletop, your cat and all kinds of unwanted items
- They can/will melt the ribbon cables and other items attached to the circuit board
- Go slow, take your time, turn it off when done, have a holder to set it in to keep it from burning stuff
---------------------------------------------------

b. Solder in the new bulbs

I used Radio Shack 272-1092 12v 60uA 10,000 hr bulbs. Cost around $1 each. You can substitute with similar bulbs or even LEDs. But, these were handy and 10,000 hrs should be enough.

Fig 09 Old and New Bulbs.JPG

i. solder in each bulb around the same height of the old bulbs.

ii. don’t replace the blue covers from the old bulbs

iii. be very careful about melting the ribbon cables and other items on the circuit board

iv. cut off the excess leads.

v. study the solder joints for bridges and other errors. Use a magnifying glass

vi. position the bulbs upright

5. Reassemble the faceplate
If not opting to replace the LCD bulbs, do the following:

a. Retrieve the faceplate keeping it facedown

b. Carefully position the circuit board back onto the faceplate. Watch that the bulbs fit into the ports.

c. Replace the torx screws, don’t over tighten, they’re going into plastic.

d. Feed the faceplate ribbon cables back through the chassis and connect to the motherboard

e. Push the faceplate back onto the chassis until the clips engage

f. Replace all the knobs

6. Reassemble the chassis

a. retrieve the CD or Cassette unit

b. plug the ribbon cables back into the circuit board

c. replace the CD/Cassette screws

d. Replace the top cover and retention screw

7. Reinstall radio

a. Replace the side brackets on the radio chassis

b. reconnect the radio wiring and antenna cable

c. slide the radio back into the console. (make sure the cowling cable is not blocked behind the radio.

d. reconnect the cable to the top of the cowling

e. replace the cowling and push pin fasteners

f. your done.

Fig 20 Completed Project.JPG

SUPPLEMENTAL
Replacing the LCD bulbs
There are two incandescent bulbs within the LCD display that are more of a challenge to replace. They are encased within a plastic frame that must be cut at to get the old bulbs out and the new ones in. If you’re not comfortable doing these steps, don’t try.

1. Removing the LCD cover

a. To get to the bulbs, the metal LCD housing cover must be removed.

b. There are four tabs soldered to the circuit board holding the housing.

Fig 15

c. Using the soldering iron and a solder vacuum, remove the solder from each corner.

d. At some point, you can use needle nose pliers to bend the tabs back so they’ll slip back through the circuit board.

e. remove the metal cover and clean the solder from the tab holes for re-installation.

2. Getting to the bulbs
Fig 16

a. the clear plastic housing the bulbs needs to be removed carefully

b. I used a combination soldering iron, dremel tool (too fast), pliers, razor blades, etc. to whittle an opening to the bulbs. This step takes time and patience.

c. there is a diffuser plate that will slip out once a plastic tab is removed. I used the soldering iron to remove the tab (careful). Remove the plate when whittling away to the bulbs.

d. CAUTION: AT all times - don’t hurt the LCD, don’t melt ribbon cables.

3. Replacing the bulbs
Fig 17

a. once the bulbs are accessible, de-solder from below and remove as with the other bulbs.

b. replace with new bulbs as before. It’s a bit awkward threading in the new bulbs. Make sure the height is the same and solder in the bulbs.

c. replace the diffuser plate

Fig 18

d. replace the metal cover and solder in the corner tabs.

e. go back to re-assemble the faceplate (5.) above.

(Opps: exceeded number of jpg attachments for the supplemental. If interested, I'll post another with the LCD pictures)

Regards

[simpsondb]

SUPPLEMENTAL (with pictures)
Replacing the LCD bulbs
There are two incandescent bulbs within the LCD display that are more of a challenge to replace. They are encased within a plastic frame that must be cut at to get the old bulbs out and the new ones in. If you’re not comfortable doing these steps, don’t try.

1. Removing the LCD cover
a. To get to the bulbs, the metal LCD housing cover must be removed.
Fig 22 Circuit Board Face.JPG
b. There are four tabs soldered to the circuit board holding the housing.
Fig 15 LCD Solder Points.JPG
c. Using the soldering iron and a solder vacuum, remove the solder from each corner.
Fig 23 Solder Vacumn.JPG
d. At some point, you can use needle nose pliers to bend the tabs back so they’ll slip back through the circuit board.
e. remove the metal cover and clean the solder from the tab holes for re-installation.
2. Getting to the bulbs
a. the clear plastic housing surrounding the bulbs needs to be removed carefully
Fig 16 LCD Cover Removed.JPG
b. I used a combination soldering iron, dremel tool (too fast), pliers, razor blades, etc. to whittle an opening to the bulbs. This step takes time and patience.
c. there is a diffuser plate that will slip out once a plastic tab is removed. I used the soldering iron to remove the tab (careful). Remove the plate when whittling away to the bulbs.
d. When finished, it should look like this with the bulbs removed:
Fig 17 LCD Bulbs Removed.JPG
e. CAUTION: At all times - don’t hurt the LCD, don’t melt ribbon cables.
3. Replacing the bulbs
a. once the bulbs are accessible, de-solder from below and remove as with the other bulbs.
b. replace with new bulbs as before. It’s a bit awkward threading in the new bulbs. Make sure the height is the same and solder in the bulbs.
c. replace the diffuser plate
d. it should look like this picture now:
Fig 18 LCD w New Bulbs.JPG
e. replace the metal cover and solder in the corner tabs.
f. go back to re-assemble the faceplate (#5. in first post) above.

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A note about the bulbs.

In this picture you can see the old and new bulbs:

Fig 21 Old and New Bulbs.JPG

The bulb at the top is the new bulb. It looks a lot smaller that the original, but does the job. The bulbs on the bottom left and right are the old bulbs. The one one the left has the blue covering still on it. The blue coverings probably shortened the life of the originals with additional heat build up.

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A note on testing

I decided to test the bulbs before re-assembling everything. If you'd like to test then :

1. feed the circuit board ribbon cables back through the chassis and re-connect.
2. take the chassis back to the car and reconnect the connector to the back of the radio.
3. CAUTION: loose wires sink ships (sort of).
You must not let the circuit board touch any metal, e.g. like the volume knob.
If you do, pop goes a fuse at best (I know).

So, be very careful in shielding the board from the chassis.

4. When you turn on the headlights, all the bulbs should light. The dimmer should change the brightness. You don't need to start the car.

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Good luck and happy soldering.

Hope this posts helps.

Regards,

Don

[OldNuc]

Nice job. This should help save those dim radios. A well written how - to.

[Motoboy10]

I just finished this project on my '95 SL1. My LCD bulbs were out as well as three of the five back lights. My radio is the CD player with EQ. The directions are good. Only thing different for the CD player is how the CD player is removed. Two screws on top and two torx behind the face plate. And only one ribbon cable. This was also my very first soldering experience. I had trouble with the vacuum, but once I figured it out it was smooth sailing. The hardest part is removing the metal cover on the LCD screen. I replaced all the back lights with the ones listed above, found at Radio Shack. I'm very pleased with the results. Thanks for the great write up. Having the clock not light up at night is one of those annoying things. I should be good for the next 13-14 years now!

Since the LCD light isn't really needed during the day light I wish we could figure away to have it work with the headlight switch like the back lighting.

[KingRex]

Typical theftlock radios!

Awsome write up!

[N80727]

Awesome write-up! Great for replacing the backlights/illumination bulbs on models with the EQ.

Did my bulbs the other day, then had to find this thread again to do my clock - Radio Shack bulb number 272-1092 works for both applications. Thanks again!