First timer needs help

[NoobInUtah]

I'm going to install a cheapo stereo in my '86 4Runner, it was stolen before I bought it, and I'm over my head.

My reciever is a Motorjoy GTO-740CD, very basic stuff. I'm not running an amp or changer.

The OEM harness was cut off, and the wires aren't any colors I recognized (Grey, White/Black, Blue, Blue/Yellow, Pink, Purple, Green, and Pale Green). A little testing with the fluke revealed that Grey is the switched power, and Blue/Yellow is constant power. Hooked those up, and ran the receiver to ground (same ground I used to ID the power wires), but I've got nothing when I turn the key.

Disregarding the speaker wires for now, the reciever has

White - panel light
Orange - power antenna (?)
Yellow - memory (constant power)
Black - ground
Red - switched power
Violet - telephone mute

Not using the phone mute, don't think I'm supposed to be using power antenna or panel light, am I? And if so, what do I splice it to?

Any help much appreciated. I know this is basic stuff, but I've been wrestling with it all day and getting nowhere.

 

[NoobInUtah]

Found this, so I guess I know I've got it wired right.

I don't know what could be wrong with the cars wiring, though. Defective reciever?

 

[mike49504]

1984-86 Toyota 4-Runner Stereo Wiring
Constant 12V+ Blue/Yellow or Blue/Black
Switched 12V+ Gray
Ground Brown
Illumination Green
Dimmer n/a
Antenna Right Front
Front Speakers 4" Dash
Left Front (+) Pink
Left Front (-) Purple
Right Front (+) Green
Right Front (-) Blue
Rear Speakers 5 1/4" Side Panels
Left Rear (+) Black
Left Rear (-) Yellow
Right Rear (+) Red
Right Rear

 

[NoobInUtah]

From the12v.com? That's what I hotlinked above, and how I've got it wired. Curious if there's any further troubleshooting I should be doing before I take it back the retailer.

 

[Perry Babin]

You need to use a multimeter to confirm that you have a good ground and 12v on the backup and memory wires.

 

[NoobInUtah]

You need to use a multimeter to confirm that you have a good ground and 12v on the backup and memory wires.

A little testing with the fluke revealed that Grey is the switched power, and Blue/Yellow is constant power. Hooked those up, and ran the receiver to ground (same ground I used to ID the power wires), but I've got nothing when I turn the key.

Thanks, I've already verified the chassis ground and 12v at the power wires.

For troubleshooting purposes, do I risk any damage to the reciever if I bring my 12v straight off the battery, as long as I'm careful not to cause a short? I'm thinking about supplying 12v straight to the power and switched power wires, and going to engine ground, just to eliminate anything in the truck wiring as defective, but I'm nervous about bypassing the fuse box. Thoughts?

 

[NoobInUtah]

Mmm. Power leads on the reciever harness have black cases that look to hold inline fuses. Haven't checked those yet...

 

[Perry Babin]

When checking the voltage on the head unit, you should touch the pins of the connector where they enter the wiring harness plug that plugs into the back of the head unit.

I don't know anything about that radio but some pioneer head units had a fuse hiding behind the wiring harness plug and you had to remove the plug to see it.

 

[NoobInUtah]

No, no fuse there. I didn't realize there was bare copper there to check for power, so thanks for that... off to hook it up again.

 

[NoobInUtah]

When you've eliminated everything it's likely to be...

I swear on my mothers grave there was 12v constant power on the blue/yellow lead when I started. I'm sure there was, because that's how I found it before I looked up the wiring diagram. It sure as hell ain't there now, though. The switched wire (grey) is fine, comes right to 12 when I turn the key.

So. Bad wire, somewhere. I'm off to hunt for the answer, but does anybody know where that constant hot comes from? Fuse panel layout http://www.4crawler.com/4x4/4R_TechI...tml#Electrical]here[/url], but I don't see anything likely. I suppose I could fuse a new wire straight off the battery through the firewall, but that seems a little ghetto. Any ideas?

 

[Perry Babin]

I can't tell you where the wire comes from but if you wire directly to the battery, you need to insert an appropriate fuse in the wire within 12-18 inches of where you connect to the battery.

 

[mike49504]

when you check to see if the deck will turn on wondering do you have the antenna plug into the deck??

I had a head unit once that wouldnt turn on if the antenna wasent plugged into it

 

[NoobInUtah]

I did try that, mike, right before I discovered I didn't have the power I thought I did.

Couldn't find a constant power source in the cab I liked, and I'm not up to tearing apart my dash right now to chase that faulty wire, so ghetto it is. I was going to have to bring a new fuse box in for aux power at some point anyway.

I've now got 4ga coming off my positive battery terminal with a 15 amp inline fuse. Then I drilled a 1/2in hole in the wheel well and grommeted it, and the cable runs down to the chassis and up through a preexisting hole underneath the passenger footspace (which I didn't know was there until I pulled up the carpet, and will now be sealed with another grommet and silicon). That'll terminate on a 6 slot fuse block fixed to the side of the consol - I'll bring my radio power off that, and hopefully run into no more hitches.

Is 15a right for the 4ga? And 7.5a in the fuse block for the radio circuit?

 

[Perry Babin]

A 15 amp fuse is certainly safe for 4g. Are you sure it's not 14g?

 

[NoobInUtah]

Yup. Thick stuff.