C4 Audio FAQ
#41
Team Owner
Member Since: Feb 2002
Location: Sometimes I wonder... why is that frisbee getting bigger? Then it hits me.
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Cruise-In X Veteran
St. Jude Donor '06
Looks like 75% of the links given in the first post are dead. Too bad, that kills alot of great info and pics.
#42
C4 Audio (SYS Issue) Help Please
Greets All,
I am experiencing the infamous aftermarket radio HU “SYS” issue in a 91 nonBose system. I have poured all over the site to find the sticky that refers to the schematic detailing the “how-to” fix and a nice thread with photos but my issue is that I do not have the OEM front end of the radio wiring harness (HU) and am using an aftermarket GM product which indicates that the dimmer and illumination wires are orange/orange and white. This is where I placed my resistors . . . I need assistance in the naming of the wires that are to be resistor connected vice gray and purple/white. Although installed, I'm still getting the "SYS". My battery tests fine and I believe that I am missing a simple step. I know that I am close to fixing this issue. Thanks in advance as any advice would be greatly appreciated.
I am experiencing the infamous aftermarket radio HU “SYS” issue in a 91 nonBose system. I have poured all over the site to find the sticky that refers to the schematic detailing the “how-to” fix and a nice thread with photos but my issue is that I do not have the OEM front end of the radio wiring harness (HU) and am using an aftermarket GM product which indicates that the dimmer and illumination wires are orange/orange and white. This is where I placed my resistors . . . I need assistance in the naming of the wires that are to be resistor connected vice gray and purple/white. Although installed, I'm still getting the "SYS". My battery tests fine and I believe that I am missing a simple step. I know that I am close to fixing this issue. Thanks in advance as any advice would be greatly appreciated.
#43
My “SYS” issue is finally solved!
Greets Again,
My “SYS” issue is finally solved.
As a follow-up, what was clearly missing per the TSB diagram is a bit of generic dialog. Per other threads, yes, connecting the purple/white and gray/black wires to resistors per the schematic (TSB) works. However no one has articulated where these cables are.
Here is the solution:
1. Locate the purple/white and gray/black wires from an OEM input wiring harness that connects to the original radio. You may have to look for it but please note that it is separate from any aftermarket wiring harness (my mistake!). Mine was located very close to the firewall directly behind the radio and led to the driver’s side.
2. Next extend the ends of both resistors (1K Ohm .5watt) via 14 gage wire (I used a soldering gun and extended mine 4 inches on each end) and connect one end to the power supply lead (preferably the AC Switch) and the other ends..one to the purple/white wire and the other to the gray/blk wire.
3. Cover all wires / reconnect the battery cable and you are done!
This process took me approximately 30 minutes and was rather easy once I figured out what I was doing.
Hope that this helps those who are having similar trouble.
My “SYS” issue is finally solved.
As a follow-up, what was clearly missing per the TSB diagram is a bit of generic dialog. Per other threads, yes, connecting the purple/white and gray/black wires to resistors per the schematic (TSB) works. However no one has articulated where these cables are.
Here is the solution:
1. Locate the purple/white and gray/black wires from an OEM input wiring harness that connects to the original radio. You may have to look for it but please note that it is separate from any aftermarket wiring harness (my mistake!). Mine was located very close to the firewall directly behind the radio and led to the driver’s side.
2. Next extend the ends of both resistors (1K Ohm .5watt) via 14 gage wire (I used a soldering gun and extended mine 4 inches on each end) and connect one end to the power supply lead (preferably the AC Switch) and the other ends..one to the purple/white wire and the other to the gray/blk wire.
3. Cover all wires / reconnect the battery cable and you are done!
This process took me approximately 30 minutes and was rather easy once I figured out what I was doing.
Hope that this helps those who are having similar trouble.
#44
Heel & Toe
Member Since: Feb 2007
Location: Grand Haven MI
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I have a '91 that had a non-Bose as well. After living with the SYS flash for quite some time with an aftermarket deck, I've decided to put in the resistors during my current stereo upgrade.
This clarification was helpful, thanks!
This clarification was helpful, thanks!
#45
Melting Slicks
#46
84 Bose
The original Bose radio/cassette in my '84 died( not surprising after 25 years! )
I bought a F series Bose CD/radio as a replacement.
My problem is..... Can I get this set to work properly? NO!
Tried all sorts of wiring combinations. Wired it with and without the shield wires connected,but makes no difference.Get one front speaker working great, other one dead or well down on volume. Rears the same or worse.The amp/speaker units are all good, so it's 'aint them.
All other functions on the head unit are fine. i.e. CD, radio tuning, ariel operation etc. Just the speaker problem.
I was told by the seller that the radio would work with any Bose equipped '84 to '89.I was also told by someone more knowledgeable than me that the F series will work O.K. on an '85 or later C4's.Is the Bose system very different on '84 Vettes to later models?
I'm based in the U.K. so getting info on this in England is not easy.
Any ideas gratefully received.
I bought a F series Bose CD/radio as a replacement.
My problem is..... Can I get this set to work properly? NO!
Tried all sorts of wiring combinations. Wired it with and without the shield wires connected,but makes no difference.Get one front speaker working great, other one dead or well down on volume. Rears the same or worse.The amp/speaker units are all good, so it's 'aint them.
All other functions on the head unit are fine. i.e. CD, radio tuning, ariel operation etc. Just the speaker problem.
I was told by the seller that the radio would work with any Bose equipped '84 to '89.I was also told by someone more knowledgeable than me that the F series will work O.K. on an '85 or later C4's.Is the Bose system very different on '84 Vettes to later models?
I'm based in the U.K. so getting info on this in England is not easy.
Any ideas gratefully received.
#47
Great FAQ, had lots of help from this when replacing my stock Bose head unit.
This was done on my 1992 and I replaced it with a JVC KW-XG701 (double-DIN radio/CD with USB/3,5 mm on the front), kept the Bose speakers via a Peripherals SVEN4 interface.
Some comments on the first post in this FAQ:
- I had no problems to unhook the antenna lead and just hook it up to the new HU, no need for any extension, adapter yes.
- For ground I used a black M6 screw (10 mm socket) that you can find if you remove the glove box and look forward on the left side of it. There are two of them attached to a big metal plate, facing forward.
This was done on my 1992 and I replaced it with a JVC KW-XG701 (double-DIN radio/CD with USB/3,5 mm on the front), kept the Bose speakers via a Peripherals SVEN4 interface.
Some comments on the first post in this FAQ:
- I had no problems to unhook the antenna lead and just hook it up to the new HU, no need for any extension, adapter yes.
- For ground I used a black M6 screw (10 mm socket) that you can find if you remove the glove box and look forward on the left side of it. There are two of them attached to a big metal plate, facing forward.
#49
Le Mans Master
I don't think anyone is manufacturing them on a commercial scale... It's easy enough to put 8" subs in the rear speaker housings, unless you're going for BIG bass, in which case the storage bins are less than ideal anyway. Just MHO...
#50
Drifting
Okay thanks.Indeed i am going for big bass. Do you think a sub box could fit in the rear in such a way that the targa can still be stowed? I'm thinking now of making my own "shallow" sub box and just putting that on top of the storage bins.
#51
Drifting
Easily. Set the top in a measure. Should be able to slope a box with 15-18in tall in the rear and angle the subs towards the front with 10-12in in the front.
#53
Drifting
No big three thread that is specific but I have done them and it helped quite a bit. I have a sub in each storage bin and 6x9s in the rear hatch 5.25 in the doors. need more mid.
#54
Drifting
Now I'm unsure of changing out the stock Bose Gold Stereo in my 1990. Is there a way to keep the stock stereo and just get 4 new amplified speakers? I read the stereo doesn't have an amplifier, each speaker has to have one?
#55
I didn't find this information in the FAQ but by searching this forum. See
http://forums.corvetteforum.com/audi...lp-please.html
or
http://forums.corvetteforum.com/audi...et-stereo.html
for a possible fix. I wil be trying this myself.
http://forums.corvetteforum.com/audi...lp-please.html
or
http://forums.corvetteforum.com/audi...et-stereo.html
for a possible fix. I wil be trying this myself.
#59
Instructor
Great FAQ, had lots of help from this when replacing my stock Bose head unit.
This was done on my 1992 and I replaced it with a JVC KW-XG701 (double-DIN radio/CD with USB/3,5 mm on the front), kept the Bose speakers via a Peripherals SVEN4 interface.
Some comments on the first post in this FAQ:
- I had no problems to unhook the antenna lead and just hook it up to the new HU, no need for any extension, adapter yes.
- For ground I used a black M6 screw (10 mm socket) that you can find if you remove the glove box and look forward on the left side of it. There are two of them attached to a big metal plate, facing forward.
This was done on my 1992 and I replaced it with a JVC KW-XG701 (double-DIN radio/CD with USB/3,5 mm on the front), kept the Bose speakers via a Peripherals SVEN4 interface.
Some comments on the first post in this FAQ:
- I had no problems to unhook the antenna lead and just hook it up to the new HU, no need for any extension, adapter yes.
- For ground I used a black M6 screw (10 mm socket) that you can find if you remove the glove box and look forward on the left side of it. There are two of them attached to a big metal plate, facing forward.
#60
Drifting