mdedddkd

I found a great fix for the typical Bose amplifier problem prone to 89-94 Maxima's. Bypass them! I don't know if this is new info to anyone, but it was to me, and I wanted to pass it along. My Maxima came stock with the Clarion made "Bose" cassette player and the Bose amplified speakers (an amp at each speaker). One rear speaker amp failed and would intermittantly produce a high pitched scream. I unplugged it about a year ago. I looked into many options, all costing several hundred dollars (I eventually purchased 2 used speakers/amps off ebay only to find the amps were bad - threw away nearly $150 on that purchase). A few weeks ago I researched how to adapt my wire harness to a later model radio (Nissan changed the radio plug design in 1995). I purchased two aftermarket harness ends (male for a 95+ model year that would push into a 95+ model radio and a female end harness that would push into my 91 model year vehicle harness). After much research on the net and at the dealer (and some test light work in the car), I made a pin out chart for each harness design which told me how to connect them together to convert my 91 wire harness to a 95+ design. Next I bought a used CD/Cassette combo deck off of ebay out of a 98 Altima. The unit was NOT a Bose specked deck (although it is made by Clarion as are virtually all Nissan factory radios - Hitachi built radios for a few models in the 80's, but I believe by 1990 Clarion was Nissan's exclusive supplier). The only difference between the Bose spec unit and the non-Bose unit is that the non-Bose unit has an amplifier built into the deck rather than preamp out to the speaker amps as in the Bose unit. My radio looks Identical to the Bose CD/Cassette decks found in 96 & 97 Maxima's except that it doesn't say "Bose" on the cassette door. Once I installed the deck, I next wired around the Bose amps at each speaker (thanks to the help of the factory service manual - each speaker has 4 wires running to it (amp power and ground and speaker left and right). Once I knew which were the speaker wires, I was able to splice the right wires together at each speaker to bypass the amps. Now I can run my Bose speakers with a factory Nissan deck (CD and Cassette too). It sounds great (all 4 speakers work now and the system sounds every bit as good as it did when amplified by fully operational Bose amps). Got a couple of bonuses too - The later model CD players are CDR compatible whereas the earlier decks that would have plugged directly into my car without any wire harness conversion were not. Also, the unit has a built in clock that can be turned on or off - in my case I run the clock since my factory Maxima clock displays only intermitantly (I believe this is also a common Maxima problem). I ended up with $95 in the entire fix including the deck, harnesses, and all shipping (Non-bose decks are much cheaper than the Bose units on ebay). A 98 Altima deck isn't the only one that will work. From my research, I believe any double-din non-Bose CD/Cassette 95 to around 2000 (depending on the model) will work. I looked at CD/Cassette decks from Frontiers, 200SX's, Altima's, Maxima's, G20's, etc and they all looked like they'd work great. What I looked for was the square double-din design, the 95+ wire harness design, and some indication that the amp was internal to the deck (cooling fins on the back was the easiest clue). In the early 90's there were a few non-Bose systems that used the same concept as the Bose units (preamp out of the deck to amps at each speaker - but with these systems, the amps were made by Clarion rather than Bose). These units were called "Active Speaker Systems". Cars that got these systems had the words "Active Speaker" on the grill of each speaker and the words "Active System" on the cassette door of the deck. Since these were early 90's systems, I don't think anyone looking for a 95 or newer deck will run into this - I believe Nissan only used this system through 92 or 93. I mention it only as an FYI. If you have any questions, I'd be happy to give you more info (if you can believe that - I've downloaded quite a lot here)! I can also email pictures and the schematic I made as well. Besides my Maxima, I own a 91 240SX LE with the "Active System" mentioned above (lucky me). It all works but I want a CD/Cassette deck in it (it's currently cassette only) so I'll be converting it next.

kobedan

What u are doing is great. Sounds like a similiar issue i am dealing with on my 94 maxima se. just purchased. the orig. owner said the radio snapped, popped,, but didn't play so good and also the power antenna was broken. ok, so i replaced power antenna ... and we had sound for about 2hrs.. then the ..it died no sound bose unit lights up, tuner works displays channels, power antenna works fine..
So i began my journey looking for the problem.. chk fuses the one i could find, under dash, out in the engine area all look good. Next, nissan dealer said there are two relays behind the driver kick panel. Yup, found the two relays... problem.. i want to basically do what you did,, how did you by pass these relays ? Also, if you have a nissan max 94wireing diagram a copy (email) would be super.. thanks.

mdedddkd

I never did anything with the relays - they're still in my car and hooked up, but they never turn on. They are inline between the individual speaker amps and the amp turn on (amp 12v +) wire that comes from the radio. When the radio is turned on, the radio supplies power to the relays via the "amp turn on" wire pin out the back of the deck. With power supplied to the relays, they are triggered to send power to the speaker amps.

On a non-Bose radio, there is no "amp turn-on" pin coming out of the back of the radio (no amp ground wire pin either). Because of this, a non-Bose deck doesn't turn on the relays and no power ever gets sent to the speaker amps.

On my car, I never worried about the relay wiring, instead my goal was to figure out how to hook the speakers up conventionally. Each bose speaker has a pos and neg terminal on it. I new the deck had pos/neg wires out to each speaker. My goal was to figure out which of the wires in each of the harnesses that plugged into each bose speaker/amp unit were the pos/neg speaker wires. Once I determined this, all I had to do was cut the wiring at each amp to hook the factory speaker wiring directly up to the speaker (thereby removing the speaker amps out of the equation). Once this was accomplished, each speaker was powered by the deck itself without going through the amps at each of the speakers.

I have a photocopy of the audio wiring schematic for my 91 SE. I can send it to you. I think it may also be helpful to send you a digital photo of what the wiring looks like when done - pretty easy to do on a rear speaker. I'll also send you a copy of how to convert your 94 vehicle radio harness connector to a 95 and later design so you can buy a later model radio like I did (keep in mind that bypassing the speaker amps requires installing a non-bose deck). If you want to stay with a bose deck, you will need functional bose speaker amps.

You stated that your radio appears to power up, but doesn't produce any sound. You may have a bad deck (it's not sending power to the amp relays) or you may have bad amp relays. You may have some other internal deck problem as well. Unless you can replace your bose components inexpensively, I'd suggest you go with late model non-bose hardware and power your bose speakers directly as I've described above. I'll think you'll be money ahead if you do - that's been my experience. The sound is great too. I'll try to email the above mentioned info to you by tomorrow (Monday) if possible.

Good luck....