Aftermarket radio install- Two ground cables needed?

[nosquirrels]

Hi all,

I'm trying to install an aftermarket unit in an '04 Pt Cruiser Base model. I've matched the cables to the new stereo wiring except that. There are two ground cables... I think.

Here is the wiring (taken from Just Crzn in this thread)

# 1 Audio R # 6 Audio L
# 2 Audio Gnd # 7 Batt Gnd
# 3 Shield # 8 (Spare)
# 4 J1850 # 9 PWD
# 5 ACC/IGN #10 Batt +

Next the 22 pin connector to Speakers Etc.
#11 Batt #22 Batt
#12 ACC #23 Radio ON Out
#13 PWD #24 J1850
#14 (Spare) #25 EVA Mute
#15 (Spare) #26 (Spare)
#16 (Spare) #27 (Spare)
#17 RF+ #28 LR+
#18 RF- #29 LR-
#19 LF- #30 RR-
#20 LF+ #31 RR+
#21 GND #32 GND

As you can see, 21 and 32 both say GND (ground, right?) but my new stereo wiring only has ONE ground wire. Anybody can tell me which one should be used? Also which "BATT" is the "constant" current and which is "switched"?

It doesn't seem like the new stereo needs it, but can anyone also tell me what the heck are "EVA Mute", "Radio On Out", and "ACC"? This is my first stereo installation so I maybe just be showing that I'm noob but if you can tell that's great!

[Kawizx9r]

One thing that simplifies things is a harness made specifically for your vehicle.

Go to Walmart, local audio stores, anywhere and you can grab a harness that; on one end connects to your vehicle's existing harness (it attaches to the rear of the stock radio) and has bare cable on the other end. Your aftermarket HU will also come with a harness described as such. Just match up the cables and you're done! Both your HU and the harness will come with a guide describing exactly what each wire is for.

As for the 2 grounds, my HU had one twice as long coming from the harness than the one from the stock/adapter harness. I simply stripped a bit of jacket near the center of the long ground cable, and attached the shorter ground cable to that. Behind the bezel, you'll see a few screws attached to the body. Get yourself some sand paper and sand off the metal surface where the screw sits to ensure proper contact with your ground cable and the surface and attach it there.

If you need anymore help, toss me a PM. Installing an aftermarket HU is as easy as changing the windshield wipers on your PT.