Electrical Schemetics/Diagrams

You might be thinking of this stuff.

AZ also has some decent diagrams and JRichker has authored some of his own as well.

Good luck.

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/

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

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

Computer, actuator & sensor wiring
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

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

Vacuum routing
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

TrophyHead said:

Thanks guys

Where is the neutral saftey switch located? Is it under the dash? I dont see it.

There's no power coming to my ignition switch. It's hard to troubleshoot this under your dash.

Click to expand...

The neutral safety switch would only prevent the starter from working if it was defective.

The ignition switch gets power from the two yellow wires in the diagram. If there is no power on them, the fuse link is blown open. The fuse links live in the wiring harness by the starter solenoid. Look closely at the diagram and you will see that the yellow wire connects to the battery side of the starter solenoid on one end and a black wire on the other. The black wire is the fuse link.

There is a FREE recall on Ford ignition switches. They overheat and sometimes catch fire.

Copy down you VIN number and call the Ford dealer nearest you. Tell them you want to see if the ignition switch recall for Fords & Mustangs was done on your car. They will ask for the VIN number & check it against the master database. If it isn't in the database, then you can schedule an appointment to have the switch replaced for free. The TSB is #95S28, and don't let them tell you that they don't do that anymore. They will not give the part so that you can install it. The rules of the recall are that they must install the switch to prevent any legal problems.

No Crank checklist for 5.0 Mustangs

Since some of the tests will bypass the safety interlocks, make sure that the car is in neutral and the parking brake is set. Becoming a pancake isn’t part of the repair process…

Check battery, terminal connections, ground, starter relay switch (also known as solenoid) and starter in that order. The clamp on with 2 bolts battery terminal ends are a know problem causer.

A voltmeter is handy if you are familiar with how to use it to find bad connections. Measure the voltage drop across a connection: more than .5 volts across a connection indicates a problem.
See http://www.fluke.com/application_notes/automotive/circuit.asp?AGID=1&SID=103 for help for help troubleshooting voltage drops across grounds.


1.) Will the car start if it is jumped? Then clean battery terminals and check battery.

2.) Check the battery to engine block ground, and the ground behind the engine to the firewall.

3.) Jump the big terminals on the starter relay next to the battery with a screwdriver - watch out for the sparks! If the engine cranks, the starter and power wiring is good. The starter relay is also known as a starter solenoid.

4.) Then pull the small push on connector (red wire) off the starter relay (Looks like it is stuck on a screw). Then jump between the screw and the terminal that is connected to the battery. If it starts, the relay is good and your problem is in the rest of the circuit.

5.) Remember to check the ignition switch, neutral safety switch on auto trans and the clutch safety switch on manual trans cars. If they are good, then you have wiring problems.
Typical start circuit...
Diagram courtesy of Tmoss &Stang&2birds


See http://www.autozone.com/images/cds/gif/large/0900823d80195963.gif for 88-90 year cars .OR see http://www.autozone.com/images/cds/gif/large/0900823d80195964.gif for 91-93 year cars. See http://www.autozone.com/servlet/UiB..._us/0900823d/80/1d/db/3c/0900823d801ddb3c.jsp for 94-95 model cars.

6.) The starter may be hung, loosen up the bolts that hold it on, and give it a good whack with a big hammer. Tighten up the bolts and try again.

7.) If that doesn't work, use a jumper cable from the positive lead on the battery direct to the starter post where the big wire from the relay connects. If it cranks then, it is the power wire from the relay gone bad. This will be hard to do, since there isn't much room to do it.

8.) Pull the starter and take it to Autozone or Pep Boys and have them test it. Starter fails test, then replace it. If you got this far, the starter is probably bad.

If not stated already, the clutch switch is on the clutch pedal's arm. There are two switches at that location so check the wiring colors in the connectors.

Good luck.

TrophyHead said:

Is the ecc relay under the passenger side kick panel? Is it a brown and black box that is an end connection?

Click to expand...

Yes. The ECC relay is located on top of the computer and can be quite challenging to get at. You may find that removing the passeger side dash speaker helps.

Small hands are also helpful, as is an eyeball on a stalk like a snail. Beware if you meet someone who has both... :

Maybe this will help...

jrichker,

Do you have a wiring diagram for the power door lock setup for a '91. I see there is one for the '86. Would the power door lock setup be the same for the foxes after '86? I have a screwy set up with my power door locks. The driver side door lock acuator actuates very infrequently but the passenger side door unlocks from both switches with no problem. I've replaced the actuator and both switches but their is no change in behavior.

Thanks,

George

AutoZone wiring diagrams

http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for 79-88 model Mustangs

http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp for 89-93 model Mustangs

http://www.autozone.com/servlet/UiB..._us/0900823d/80/1d/db/3c/0900823d801ddb3c.jsp for 94-98 model Mustangs