Strange electrical problems mainly on drivers side. HELP please.

[jmyer333]

I am experiencing some strange electrical issues on my 93 LX. I just finished putting the car back together and when I hook up the battery the interior dome light comes on and wont turn off. Also, the left side of the guage cluster and left turn signal will not illuminate. The power door locks & windows don't work either. Another wierd thing is that the power mirrors only work when the toggle is switched on to the passenger side, (does not work when its switched to driver side). Could this all be due to a bad ground? I have checked them and I think they are good. The battery is in the trunk but I have a terminal block up front with all the power wires running to it. Any advice or troubleshooting would be greatly appreciated!

 

[Boss91GT-SC]

Sounds like a grounding issue. How is your battery grounded.? I have mine in the rear hatch and grounded to the frame in the rear and ran a ground to the front frame and to the block at the original location as if your battery was still under the hood.

 

[Noobz347]

It does sound like a ground issue but I would hazard a guess that the bad ground is under your dash somewhere.

 

[jrichker]

Diagram courtesy of Tmoss & Stang&2birds

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

 

[Smooth0087]

I have this exact same problem. I recently reassembled my 1987 GT after several years and have no power to the power windows, or part of the gauge cluster. Has anyone resolved this?

 

[jrichker]

I have this exact same problem. I recently reassembled my 1987 GT after several years and have no power to the power windows, or part of the gauge cluster. Has anyone resolved this?

Get out your DVM and check out the link I posted with the other diagram. The power window diagram for earlier model cars is on there too.

Here's the link for 87-92 power windows...
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

 

[Smooth0087]

Thanks so much. I solved the issue with the windows (drivers side connector under the dash going to the door unplugged) But my gauges still do not work. Tachometer, Oil, Temp, Fuel, and Battery will not work. They do not even reset when you turn on the key. Does anyone have an ideas on what might be the issue? All the lights on the cluster work accept for the 4 indicator lights on the bottom for fuel, coolant, ect. that the 87-89 GT's have. My fuses are all good and I have swapped clusters and it still is getting no readings from the sensors I gather. Any help will be greatly appreciated.