First gen wiring problem

[Toyotafan03]

Ok so I've done searches before I decided to start this thread and just couldn't find anything that specifically helped my problem. Had to take the dash apart to change my Heater control unit. Before I took it apart the radio was working and the clock was working. Now that I started putting everything back together, the clock won't light up at all, and the radio will turn on until you plug in the clock or put the cigarette lighter into the hole. If you do either one of those things the radio automatically shuts off. It also does it whenever I put a test light to either one of the hot wires to the cigarette lighter or the clock. I've checked all the fuses and they are all good even the one in the back of the radio. I have ZERO experience with wiring and I don't even know where to begin to start trying to solve the problem? Any input will help greatly!!

 

[flyinhawaiian01]

Bad or missing ground somewhere in there? That's my thought. Try running a jumper wire from a part of the frame inside the dash to the bracket on the radio, see if that helps.

 

[RAD4Runner]

... I have ZERO experience with wiring and I don't even know where to begin to start trying to solve the problem?

Start by getting yourself a digital multi-meter.

Radio is very sensitive. A slight voltage drop, like that caused by cranking will make it reset. high resistance in the wiring from poor connections or weak battery will cause voltage to drop below what radio likes.

 

[Toyotafan03]

Have tried running a jumper wire... No help at all. And have redone all the connections and still can't find the problem! This is stumping me and holding me back from finishing the dash... Anyone have any thoughts on what else to try?

 

[flyinhawaiian01]

Is it a stock radio? Is the battery fully charged? When you say put the cigarette lighter into the hole, are you saying that the lighter doesn't get hot? Is the lighter's filament getting hot at all or just nothing at all from it?

This all points to either a bad ground, which you have already ruled out, or a bad battery. There's no other logical reason for the radio to shut down if you plug the clock in, as it doesn't pull much more than a quarter amp (if that) when lit!

Get a multimeter and check to see what voltage you're getting at the dash. You need to see the numbers, not just a light. You will need to see around 12 volts at the dash. Reverse the wires and start testing your ground wires too. You'll need to hook up the red lead from the meter to +12VDC, then probe your ground wires to make sure the voltage is still 12 volts. And with that, I'd also run a good wire from the negative side of the battery straight to the test lead of the meter to make sure you're not getting any false readings. You can use jumper cables to "extend" the negative test lead to the cab.

 

[Toyotafan03]

I ran a hot wire from my battery to the constant hot, and the radio still cut off when I plug the clock in. So then I ran a hot wire from the battery to the other hot wire. And when I plugged the clock in the radio stayed on that time. So I'm thinking I've got a problem with the ground on my hot wire? I'm at a lose here and at then end of my knowledge with wiring. Any advice would be great!