HDS Gens Touch shows positive red to negative & black to positive?

If it's only 4 wires, Red & black are typically power. red +12volts & black is ground. Gray would be one channel say right side and green would be left (example) you would ground the negative speaker lead on both sides. That is probably an old unit and make sure your car is negative ground. Some Ford & Nissan are positive grounded for some circuits which you may need to reverse the power connections. Make sure there is an in line fuse on the power wire just in case.

INDUSTRY STANDARD WIRE CODE COLORS FOR CAMMERAS ARE AS FOLLOWS

RED- POWER SUPPLY POSITIVE
BLACK - POWER SUPPLY NEGATIVE
WHITE- VIDEO CENTER
YELLOW- AUDIO CENTER
THE SHIELDS ON VIDEO AND AUDIO HAVE TO BE JUMPERED TO BLACK - POWER SUPPLY NEGATIVE

NEVER ALLOW POWER SUPPLY POSITIVE TO TOUCH VIDEO OR AUDIO LEADS

Hi

The black wire will be connected to the body or engine of the van and the red or positive wire is connected to your starter motor.
You can also use a 12 volt battery light to check the negative or positive wires.
You take the 12 volt battery light and place the negative black wire clip to an earth on the vehicle, then when you touch the tip of the 12 volt battery light onto a positive wire the light will light up.
Then you will know which wires are negative or positive sometimes the key has to be on for some wires to work.
Cheers

yes, there is an amp turn-on wire from the head unit (black with a red stripe). You will need to add a power wire and fuse from the fuse box to run the amp. You can use the speaker outputs as inputs to the amp, depending on what you are trying to do. Please let me know if you need more help, and identify the amp model as well as the speakers you will connect.

Car Radio Battery Constant 12v+ Wire: Blue/Yellow
Car Radio Accessory Switched 12v+ Wire: Gray
Car Radio Ground Wire: Brown
Car Radio Illumination Wire: Black/Red
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: Black/Red
Car Stereo Amplifier Location: Under the center console.
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Pink
Left Front Speaker Negative Wire (-): Violet
Right Front Speaker Positive Wire (+): Green
Right Front Speaker Negative Wire (-): Blue
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Black
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Red
Right Rear Speaker Negative Wire (-): Yellow

The TS55 is a DVC subwoofer that can be wired for either 4 ohms (voice coils in series) or 1 ohm (voice coils in parallel). The appropriate wiring depends on the amp.

If the amp is stable at 1 ohm, wire both positives and both negatives to the matching amp output terminal (parallel) as shown in Wiring Option #1.

If the amp isn't stable at 1 ohm, connect a jumper between the positive on one voice coil and the negative on the other voice coil. Then connect the remaining positive and negative to the matching amp output terminal (series) as shown in Wiring Option #2.

http://www.rockfordfosgate.com/rftech/woofer_wizard.asp?submitted=true&woofer_qty=1&woofer_imp=3

If this helps you then please help my rating,voting for me would be great too thanks.

Black - Ground
Blue - Power Antenna / Control for an AMP
Orange - Constant 12 Volts
Red - 12 Volts when the ignition is on, 0 Volts when it's off

[Speakers]

[Front]
Gray - Front Right Positive
Gray Black - Front Right Negative
Green - Front Left Positive
Green Black - Front Left Negative

[Rear]
Gray Red - Right Rear Positive
Black Gray - Right Rear Negative
Green red - Left Rear Positive
Black Green - Left Rear Negative

Here is the breakdown of what wire does what:
+Red..............12v ignition
+Yellow...........12v battery
-Black............Ground
+Blue.............Power antenna
+Blue/white.......Remote turn on
Orange...........Dashlight/dimmer
Orange/white.....Dashlight/dimmer
Orange/black.....Dashlight/dimmer
+White............Front left positive
-White/black......Front left negative
+Grey.............Front right positive
-Grey/black.......Front right negative
+Green............Rear left positive
-Green/black......Rear left negative
+Purple...........Rear right positive
-Purple/black.....Rear right negative

You only need the red and black wires to supply power to the unit. The red positive wire goes to a positive terminal on your battery or positive side of a bus bar or switch, the black negative wire goes to the negative terminal on the battery or negative common bus bar. Do not try to earth the black wire to an aluminum boat hull... You are asking for trouble! Best to run the black wire straight back to the negative battery terminal or negative bus bar that is wired to the negative battery terminal. The other colored wires on the 160C plug are used for interfacing with NMEA2000 compatible devices, like a compatible GPS.

You do not need the data cable connected unles you are hooking it up to other electronics, ie computer, second GPS sounder ect. You only need to conect the red to the positive on the battery and the black to the negative.