Why is there sound output when using am/fm but none when playing a CD?

Do you have base or up;level system ?

Table 1: Radio Features
Table 2: Cassette Features
Table 3: Compact Disc Features
Table 4: XM Advisory Messages
The radio receives power from the RADIO fuse in the junction block-right I/P. Ground is provided via G201 and G202. The radio is enabled/disabled by class 2 messages from the body control module (BCM). The radio routes audio signals from the digital radio receiver or the vehicle communication interface module (VCIM) to the speakers and/or amplifier when directed by class 2 messages.
The Entertainment System on this vehicle is configured with an AM/FM stereo radio with the radio data system (RDS) and either a cassette player or a CD player or both. CD and cassette. The uplevel system provides the customer with extended range speakers and an audio amplifier. Satellite digital radio (U2K) is available with uplevel systems.
The following list shows the radios available for this vehicle:
• Radio (ULO) - AM/FM Stereo, Cassette with RDS
• Radio (UNO) - AM/FM Stereo, CD and RDS
• Radio (UPO) - AM/FM Stereo, Cassette with CD and RDS .The complexity of the radio systems on these vehicle is mind blowing .

Your best bet take it to a GM dealer , has features you are unawear of .
DTC B1025, B1035, B1045, or B1055
When the radio is powered up, the radio supplies low level audio signals to the speakers. If the vehicle is equipped with an audio amplifier, the amplifier will boost the signal sent to the speakers.
DTC B1025 Audio Output Circuit
Install a scan tool.
Turn ON the ignition, with the engine OFF.
With the scan tool, monitor the DTC Information for DTC B1025.
Does the scan tool indicate that DTC B1025 is current?

Maxima Bose Radio ' eBay

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eBay1995 1996 1999 Nissan Maxima Pathfinder Infiniti J30 Radio BOSE CD tape Player ...Will fit and work in these with BOSE audio package only:1995 - 1999 NISSAN .... 2006Nissan Maxima OEM Bose Cassette & 6 Disc CD Player Radio CR13B ...DESCRIPTION Unit is missing some bottons, 3 of them, this item has NOT ...

Nissan Maxima Bose Stereo ' eBay

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eBayWill fit and work in these with BOSE audio package only:1995 - 1999 ... 1996 - 2000 NISSAN Pathfinder. 2004 2005 2006 NISSAN MAXIMA FACTORY BOSE STEREO 6 DISC ... Factory NISSAN INFINITI BOSE Radio, Tape, and CD Player. ... 6 Disc AM FM Stereo Cassette Radio Bose OEM LKQ (Fits: Nissan Maxima).

Nissan Maxima Car Stereo Removal and Repair - YouTube

? 8:52
https://www.youtube.com/watch?v=RT-SZEfeA4Q
Sep 16, 2012 - Uploaded by Factory Car Stereo Repair
Factory Car Stereo Repair .... I have nissan maximal 05..the CD part turns on but the cd won't eject...should ... I have a 2005maxima non-bose radio system. ... my speakers is super in my 05 maxima but my cd player keeps on ...

Nissan - Factory Car Stereo Repair

Sounds like a loose/bad/corroded speaker output from the stereo.
That's what usually causes an intermittent problem in an otherwise working system.

call your local dealer and set an appt with the stereo person that is the easiest fix as you have a decent system or find a qualified stereo guy to look at it make sure the person has worked on caddies b4 letting the stereo person touch it

I am not sure about repairing the unit. Do you have a CD cleaner?
You might check with a reputable auto electronics shop, one that specializes in car audio. They may have an adapter that will allow an aftermarket radio to be controlled from the steering wheel. Rosen makes a nice am/fm/cd/dvd navigation unit that also has XM and iPod inputs. The hard part will be to find supporting interfaces and wiring harnesses to fit a 99.

You most likely need a new radio. They go bad all the time in the Chrysler/Dodge/Jeep. Don't know how many of them I have replaced.

I have come to find out that in the 90's auto makers started installing factory amplifiers in their cars so they could use low wattage stereos in the dash. It's usually a blue wire off the stereo that runs the amp, maybe it couldve become disconnected? I also know that even if you put in an after market stereo, this wire must be hooked up or you'll get no sound from the speakers. hope this helps.

I searched quick and couldn't really find anything on a manual eject button. Flip through the manual a little bit and see what it has about the radio. If all else fails and you aren't worried about possibly breaking the stock cd player, some skinny needle nose pliers should reach in far enough to grip the cd and you can pull it out. But there is a good chance you could break the cd player in doing so.

I would suggest checking the owner's manual on what the button does, but you could always buy an FM Transmitter hook it up to your Zune and play music from an empty station.