Question about Pioneer DEH-P840MP CD Player

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Repair no.3 This repair--rear display doesnt light does the cd player works..however the ability to tweek the system is no more due to this problem....i was able to get by for several months...but i put a new battery in, and id like to tweek the system back to par. --i realize there were more posts similar to mine but i am on a dialup connection....enough said I appreciate your help Craig

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Re: Repair no.3 - Pioneer DEH-P840MP CD Player Car Audio Receivers


Posted on May 13, 2008

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What cause the display to go out on the kenwood kdc-235 cd player

Hi there,

You could try reading my tip on repairing Kenwood faceplates.

How to repair Kenwood Faceplate


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Cd player wont work / chrysler voyager 2001

if the radio lights are flashing the radio needs to be repair or replace, it is not a simple fix the radio power supply got damage when you replace the car battery happends a lot to Dodge Chrysler vehicles

you can also get a rebuild radio from here

Mar 31, 2010 | Car Audio Receivers

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Cd in sony cd player in ford focus car. readout says "no CD" yet still plays


Turn Off and On the player twice or thrice. Sometimes, it might work. Make sure you have the Genuine and compatible CD/DVD. Use some other Cd.If the problem remains the same, the issue is with player.

I have seen many times, this message occurs due to faulty player lens who sense the CD/DVD. Try to use a lens cleaner.If that would resolve the issue.Perfect unless you need to send the unit to repair or remove the player from the dash and repair it. It can be a circuit issue as the player is unable to sense the CD/DVD.

Let me know, if need further assistance.

Hope i helped you.

Thanks for using ' Fixya ' and have a nice day!!

Oct 09, 2009 | Car Audio Receivers

1 Answer

My auio just doesnt work.

This sounds as if the output amplifier has failed.
Professional repair is necessary.
To check the rest of the radio is functioning properly, use the low level outputs (RCA) to an amplifier.
If you have sound, the internal amplifier is blown.
The repair shop you take it to should be able to bench test it for a nominal fee that usually comes off the repair bill.

Thanks for using FiXya - A FiXya rating is appreciated!!

Jan 22, 2009 | Alpine CDA-9856 CD Player

1 Answer

DPX-501 LCD Repair

I got the new display part from the Kenwood supplier on LI, NY but there are dozens of pins on lining both sides of the display, each 1/16" from the other. I don't have confidence in my ability to detach the old and solder the new to the main board without further disaster.

Choices for me now are:

- continue "flying blind" - most likely solution for the moment.
- pay someone to do it - includes removal and being without a head unit for an unspecified time, plus cost.
- replace - I'd like to change brands although it means replacing the Kenwood satellite unit too, so more cost.

This hasn't been a good advertisement for Kenwood. People are impressed by the sound in my car, but not so much by the blank screen, guesswork changing stations etc.

I really like the unit, and the display was great while it worked: exactly as long as the warranty. I can't recommend Kenwood.

Aug 19, 2008 | Kenwood DPX-501 CD Player

1 Answer

Display lights

You need to tie them( the stereos lights) into your dashes dimmer switch wiring. This is what that YELLOW wire is for or didn't you read the manual for the stereo unit. Locate your vehicle owners manual. Some have a wiring diagram in the final pages or look for the exploded view of the fuse block. You can tie in through this. If there is no diagram in the rear of your vehicle manual, go purchase the backyard repair manual(Chilton's, Motors, Haynes,etc) or go to the dealership and purchase the wiring/repair manual from them(at an exorbitant cost). OR you could just take it to an installer and pay them the money to correct this issue.

Jul 27, 2008 | Dual XDMR7710 CD Player

3 Answers

Display light burnt out

Solution #2 is incorrect. Alpine service charges a flat $95 for repairing a CDA-7998. How do I know? I sent mine in two weeks ago and got it back a few days ago. They

1) Replaced the burned-out biolite display
2) Replaced the fantomface cam gear
3) Replaced the main logic board
4) Cleaned the laser/pickup optical assembly

Charge: $95 including return shipping.

Apr 27, 2008 | Alpine CDA-7998 CD Player

2 Answers

Kdc-x879 won't recognize cd feature

I am sorry to tell you this, but there is no easy fix after pressing the reset button. The unit is not even recognizing the cd player, so it could be one of many different problems, all of them being electronic and inside the unit.

It could be a voltage regulator that supplies the cd deck, it has 3 of them. It could be the ribbon cable that connects the cd deck to the main board, but that is more unlikely. It could even be the microprocessor.
There is just no way to be certain without putting it on a test bench and troubleshooting it with the schematic in front of you.

If you have some electronic troubleshooting skills, I can email the schematic to you. I have it in PDF format and you can check it out as long as you have a power supply, multimeter and knowledge of electronics.

Otherwise, you will need to take it in to an authorized Kenwood repair center.

I hope you found this helpful, but you do have a serious problem with the unit.

I have been repairing these type of radios since they started making them a couple of years ago and this problem has had several different fixes for this same symptom and it has never been an easy fix.

let me know if you need more help

Oct 17, 2007 | Kenwood eXcelon KDC-X879 CD Player

8 Answers

Alpine head unit CDA-9855R

Yes, I'm sure Alpine will sell you another face but there is still the option of repairing the broken face at a good repair shop. Of course getting a new face is the easiest (read most expensive) way to get you going again.

Jun 08, 2007 | Alpine CDA-9855 CD Player

1 Answer

KDC.716S Mech error issue

Try the tiny reset button on the front just below the volume down button.

Nov 10, 2006 | Kenwood KDC-716S CD Player

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