How-To: Alpine CDA-7930 Display Repair

By: Richard Vedvik (keep_hope_alive)

The display on my CDA-7930 was busted, like many LCD’s they are fragile and easily broken, for instance; if you try to secure the faceplate by pushing on the display.

Luckily a replacement display is cheap - $20, and like all Alpine parts is available through pacparts.com. This faceplate was worth saving for that price. It helps to have a service manual for any project like this. They're around $10 and worth every penny.

Before the project:

Read on for the whole process...

(Click the pics to enlarge)

The following tools are required:

• Soldering Iron
• Solder
• De-soldering wick
• Needle nose pliers
• Mini screwdriver set
• Wire cutter (for the wick)

Optional but helpful is a power supply for quick testing, below is a picture of the "work bench".

Before the repair this is what the display looked like.  You can see how the broken parts are constantly lit. 

This is a schematic view of how the LCD display is internally connected.

An exploded view shows how the faceplate goes together

The whole process takes an hour.  Start by removing the two screws from the back of the faceplate and pull off the volume/control knob.  This is where you'll use a small Phillips jewelers screwdriver.

Gently pry the faceplate apart, take care to not gouge the plastic face.  The board holding the display can be removed, there are a few tabs that secure it.  The display is held onto the board with five small tabs.  The tabs are soldered to the board.

The five tabs are circled in red

Using the soldering iron and de-soldering wick remove the solder completely. Once all five tabs are clean they can be bent straight.

The display will come off as the tabs come through the holes.  A small flat screwdriver can be used to carefully separate the board and display.  Make sure the tabs are completely straight and line up with the holes first.

Discard the broken display and insert the new display into the case. The large white piece is what provides back illumination and guides the traces. The traces will be the last piece to reinstall. Make sure they are clean and that there is no dirt or film on the ends, otherwise you won’t get a solid connection and some of the traces will be blank.

Before you solder the tabs, test fit and power up the display.  My first two attempts were not perfect, but third time was the charm.  You must get the rubber traces perfectly aligned.

Once it's working perfectly solder the tabs.

The completed product is good as new!

Editor's Note: This will be the first of a few installments provided by SoundDomain's moderators on how to repair or customize your radio. Stay tuned for a great article on How To Customize Your Faceplate's LED Color!

Richard Vedvik is an Electrical Engineer for KJWW Engineering Consultants, an avid hobbyist with electronic circuit design, home A/V and car audio, and is a Moderator for the SoundDomain forums (keep_hope_alive) and a CarDomain member.

Comments

[Pressed_Ham]

wow

[Robert Haynes]

Please I WOULD LIKE TO PURCHASE 2.8 VOLT MICRO LAMPS AND A SERVICE MANUAL, Alpine.

[Robert Haynes]

Please I WOULD LIKE TO PURCHASE 2.8 VOLT MICRO LAMPS AND A SERVICE MANUAL, Alpine.