If it is not a factory stereo, you will need a GM class2 data bus interface device in order to keep other car devices active.
Chances are its a wheel speed sensor and will need the wheel bearing replaced. or it can be a loose or corroded wire attached to the sensor as well.
There are for stereo wiring color codes. The red wire is the positive wire. The black wire is a ground wire. The green wire is the speaker wire. The white wire is the auxiliary wire.
http://www.modifiedlife.com/1995-pontiac-bonneville-car-radio-wire-diagram/
2003 Pontiac Sunfire Car Radio Stereo Audio Wiring Diagram Car Radio Battery Constant 12v+ Wire: OrangeCar Radio Accessory Switched 12v+ Wire: The radio harness does not provide a switched power source. Run a wire to the fusebox for switched power.Car Radio Ground Wire: BlackCar Radio Illumination Wire: GrayCar Stereo Dimmer Wire: N/ACar Stereo Antenna Trigger: PinkCar Stereo Amp Trigger Wire: N/ACar Stereo Amplifier Location: N/ACar Audio Front Speakers Size: N/ACar Audio Front Speakers Location: N/ALeft Front Speaker Positive Wire (+): TanLeft Front Speaker Negative Wire (-): GrayRight Front Speaker Positive Wire (+): Light GreenRight Front Speaker Negative Wire (-): Dark GreenCar Audio Rear Speakers Size: N/ACar Audio Rear Speakers Location: N/ALeft Rear Speaker Positive Wire (+): BrownLeft Rear Speaker Negative Wire (-): YellowRight Rear Speaker Positive Wire (+): Dark BlueRight Rear Speaker Negative Wire (-): Light Blue
You can easily get all of the color codes for every wire on the 1998 Pontiac Grand Prix. Pontiac has an official website homepage that has all the information on it.
run wire from red power wire on stereo to fuse panel .crimp blade terminal on the wire and slide it into one of the ignition (ign) slots
is this on the stereo/head unit? if there's no visible socket its proberly on the rear of it, which means taking it out :(
just hook it up to a wire with power when the key is turned on the same wire that turns on your stereo just change the fuse to your stereo from a 10 amp to a 15 amp
in the red or white at the back of the speakers
A 1989 Pontiac stereo wiring diagram can be obtained from most General Motors dealerships. The wiring diagram can also be found at most auto-parts stores.
I spoke with a technician at Scosche 1(800)621-3695, and he said the wire harness that was needed is a GM07, there is no need to buy a $150.00 stereo wire harness, because the only bonniville's that support that harness were the 2005 and up models. just in case your wondering the dash kit model # is GM2049, that is for a 2000 Pontiac bonniville.
Tap into the dash illumination fuse in the fuse block.