OK Tech Heads...Here's One for Ya.

["Mongoose"]

When I turn on the ignition key, the EEC fuse blows.
I've done everything from unpluging the CCRM, the fuel pump,
traced the wiring harness from the fuse block to the EEC.
The wiring is in solid condition, the CCRM is new, and the fuel pump
works fine.(I jumpred the the pump just to make sure)
Please fire away any and all ideas.

 

[shttygtstang]

well this might sound not so good but when i have a short i a wire and cant find it i stick tin foil on the fuse let it run till it catches fire . It will ignite were its grounding out

 

[89white50]

LOL!!!!!!!!!!!!!!!!!! i would just keep looking for a grounded wire before TRYING to set my car a blaze

 

[shttygtstang]

well first ide break down the hole wiring loom and look but it works hey

 

[Dbeck002]

Thats a good way to melt one wire and all the ones next to it and short every single circuit out lol...

 

[ss93cobra]

Doesn't sound like fun, but what about doing a continuity test?

 

[jrichker]

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-90 wiring

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

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif

 

[jrichker]

Keep in mind that fuse #18 does not feed either the ECC or fuel pump circuits.
If this is the fuse that keeps blowing, the problem is not likely to be in the ECC or fuel pump hardware.

Remove the passenger side kick panel. Then loosen the 10 MM bolt from the center of the big connector. When the bolt spins free, pull down on the connector assembly. Replace the bad fuse and apply power. If the fuse does not blow, you have a bad computer. If the fuse does blow, then you get to Ohm out the wiring on pins 37 & 57. You should see more than 100 ohms between these wires and ground.

Note that the same circuit also feeds the fuel pump power. Remove the fuel pump relay located under the driver's seat. Replace the bad fuse and apply power. If the fuse does not blow, you have a problem in the fuel pump circuit.

Diagrams courtsey of Tmoss & Stang&2Birds.

 

[HISSIN50]

As J.R. SO wisely and often says, you need to provide information about the year of your car, accompanying modifications, etc. Otherwise it can delay people being able to help you.

I assume you have a 94-95 since you mentioned the CCRM (Constant Control Relay Module). Correct? The wiring paths are a bit different on an SN vs a fox (SN having the CCRM, underhood fusebox, etc).

I know Tom has authored an SN diagram or two and S+2B's is hosting them on his site. But I dont think it is anything that can help you out much.

I mainly wanted to atleast get the year of car straight. Good luck.

 

[jrichker]

AutoZone wiring diagrams

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

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

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

 

[stangjunkie]

WOW..... pretty colors....

 

["Mongoose"]

Well, I must say you guy's are very good.
The information you've given me has payed off greatly. The diagrams were very helpful.
Tracing the problem rite to the #3 f/i plug.
After hours (days & nites) of testing and retesting, tracing and retracing the info
you gave me played a major roll in finding the falt and a quick fix.
I can't say thanks enough!!!
Thanks and off to the dyno we go.

 

[HISSIN50]

Another Jrichker success story.