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HELP sys on and off on LCD display

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Old Jan 3, 2011 | 07:27 PM
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Default HELP sys on and off on LCD display

I installed a new radio this weekend pioneer 50 w total and 2 front 5 1/4 pioneer speakers.
On the way home today after work my sys keeps comining on in the dash.
I finished the install of my 6 x 9 speakers tonight.Now during Base w/ radio turned up my radio cuts off and on almost like a skip in the cd but the lights go dimm during the base.
Things I found.
Volts only at 13.8 on dash so I cleaned both terminals now I have 14.0 volts on dash.
I checked with my volts meter at the alternator,car running and get 14.18 at the battery I get 13.88.
The positive terminal was coroded a little.
The battery when car is off is reading 12.3.Car starts right up not a slow start at all.

I dont think this problem is the radio.
I did unhook the battery during the install.
Can you pull codes from a sys like the service engine soon?

Last edited by tblt44; Jan 3, 2011 at 07:30 PM.
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Old Jan 3, 2011 | 07:46 PM
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See if any of this helps. It's a well known issues that installing an aftermarket stereo can cause that in some cars.

From the Audio Section:
http://forums.corvetteforum.com/audi...audio-faq.html

And the TSB for the SYS:
http://www.corvetteforum.net/c4/dave8476/index4.shtml
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Old Jan 3, 2011 | 08:03 PM
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Ok if I have to install a resistor or 2 can someone tell mt where to put them,I'm not to good when looking at that diagram.
I used the cruchfield wiring harness,just pluged it in behind the seat and wired it up to my new radio.
I wired the ground to the black wire to the wiring harness,should I have grouned another way ?? to frame or battery?
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Old Jan 3, 2011 | 08:27 PM
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Ok I keep looking at the diagam and just can't figure out where the resistors go.
Is it to the power and ignition power wire at the back of the reciever?
I don't think so but I will ask.
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Old Jan 3, 2011 | 09:41 PM
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Ok I now have 14.3 volts so I think my problem is a ground or I need the resistors.
Can anyone tell me in none electrical terms where to put the resistors.

like the pink wire under the dash coming from the fuse box for radio(example only)
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Old Jan 4, 2011 | 09:03 PM
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Ok here's my lame diagram
where do I put the resistors
I am so lost

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Old Jan 5, 2011 | 11:38 AM
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Maybe this will help?

If "SYS" is displayed in the LCD section of the instrument panel cluster after the customer installs a new (aftermarket) stereo, he will need to do the following:

1. Buy (2) 1 kilo-ohm 1/2 watt resistors. [Radio Shack part # 271-023. They sell them as a 2pk for .29 cents.]
2. Disconnect the negative battery cable.
3. Remove the receiver.
4. Connect one end of both resistors to ignition power. (Yellow wire in the car)
5. Connect the other end of one resistor to the purple/white wire in the car.
6. Connect the other end of the second resistor to the grey/black wire in the car.
7. Cover all connections and completely cover the resistors.
8. Reconnect the negative battery cable.
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Old Jan 5, 2011 | 12:16 PM
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The Resistors attach to the old wire harness that was removed from the back of the stock head unit.
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Old Jan 5, 2011 | 06:26 PM
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Originally Posted by Red Dwarf
Maybe this will help?

If "SYS" is displayed in the LCD section of the instrument panel cluster after the customer installs a new (aftermarket) stereo, he will need to do the following:

1. Buy (2) 1 kilo-ohm 1/2 watt resistors. [Radio Shack part # 271-023. They sell them as a 2pk for .29 cents.]
2. Disconnect the negative battery cable.
3. Remove the receiver.
4. Connect one end of both resistors to ignition power. (Yellow wire in the car)
5. Connect the other end of one resistor to the purple/white wire in the car.
6. Connect the other end of the second resistor to the grey/black wire in the car.
7. Cover all connections and completely cover the resistors.
8. Reconnect the negative battery cable.
I ran the new harness from behind the seat.
Do I connect from the radio to the old harness in the dash or will I be connecting to wires behind the seat.I am thinking from the old wires I have unpluged behind the reciever.
So both resistors go to the SAME power wire with ignition on correct.

Ok I just saw GKK post I think I got it now.
I will take pic's for the next guy that has problems
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Old Jan 10, 2011 | 07:08 PM
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got it.easy
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Old Jan 10, 2011 | 11:54 PM
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Originally Posted by tblt44
got it.easy
It's always something. Hope it's an easy fix for you .
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