Dash harness

[Rmach1]

Have any of you ever experienced a warm under dash harness or any harness that becomes warm to the touch?

All grounds are good and clean and when I installed the headlights, the turn signals in front won’t blink

When I remove the actual headlights, they work. All this and the harness wires are warm. Any suggestions will be greatly appreciated.

 

[midlife]

There are anywhere from 2 to 3 resistor wires buried in the underdash harness. When operating, they will cause it to be warm to the touch, but not hot.

1. Coil resistor wire runs from fuse box to either tach plug or back of the fuse box. Always on when key is in RUN position.

2. Alternator indicator lamp resistor wire: only works when bulb is broken.

3. Dash cluster CVR input resistor wire: runs from back of wiper switch to dash cluster connector. Always in operation. Will become hot (not warm) if CVR output gets grounded.

 

[Don C]

Light conflicts are generally caused by bad grounds, from housings to ground, wires to ground, or bulb bases not making good contact with the socket. All grounds have to be to bare metal, paint is a good insulator. The battery ground has to be connected to the chassis at the voltage regulator and the engine block.

Electricity seaks whatever path has the least resistance, whether it is direct or through other circuits. Bad grounds can cause all kinds of weird symptoms as they loop through other circuits.

 

[Carolina_Mountain_Mustangs]

I hate electricity cannot they make it mechanical?

 

[Rmach1]

There are anywhere from 2 to 3 resistor wires buried in the underdash harness.  When operating, they will cause it to be warm to the touch, but not hot.  

1. Coil resistor wire runs from fuse box to either tach plug or back of the fuse box.  Always on when key is in RUN position.

2. Alternator indicator lamp resistor wire: only works when bulb is broken.

3. Dash cluster CVR input resistor wire: runs from back of wiper switch to dash cluster connector.  Always in operation.  Will become hot (not warm) if CVR output gets grounded.

Thanks for the info!

 

[Rmach1]

Light conflicts are generally caused by bad grounds, from housings to ground, wires to ground, or bulb bases not making good contact with the socket. All grounds have to be to bare metal, paint is a good insulator. The battery ground has to be connected to the chassis at the voltage regulator and the engine block.

Electricity seaks whatever path has the least resistance, whether it is direct or through other circuits. Bad grounds can cause all kinds of weird symptoms as they loop through other circuits.

Thnx will check all ground points

 

[Rmach1]

There are anywhere from 2 to 3 resistor wires buried in the underdash harness.  When operating, they will cause it to be warm to the touch, but not hot.  

1. Coil resistor wire runs from fuse box to either tach plug or back of the fuse box.  Always on when key is in RUN position.

2. Alternator indicator lamp resistor wire: only works when bulb is broken.

3. Dash cluster CVR input resistor wire: runs from back of wiper switch to dash cluster connector.  Always in operation.  Will become hot (not warm) if CVR output gets grounded.

Thanks for the info!

 

[Rmach1]

Well, my mechanic worked it all out

He had to substitute the backup switch part of that harness with another switch because the bracket had no mounting point but the four plug mated correctly at the firewall

He replaced the turn signal switch harness and it corrected the brake light issue. I adjusted the switch under the dash previously and had brake lights on the driver side and the new TS switch did the trick

The headlight issue was resolved when he checked the wires on the after market lights and fixtures. They were crossed from the factory so he swapped them and now they work in conjunction with the front turn signals...

Hope this info helps

 

[icejawa]

Glad your mechanic actually has a brain, I made the mistake of taking my Mach to one and he ended up destroying my dash harness. He wanted $900+ for the "work" he put in. I had to send it to Midlife (thank god for him) and have not used a mechanic for any work on my valuable cars ever again. Good to hear you got it solved