1994 Mustang Conv 3.8L under dash fuse #18 Blowing

Discussion in '94-04 - V6 Specific' started by DavidMustang, Mar 21, 2015.

  1. DavidMustang

    DavidMustang New Member

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    1994 Mustang Conv 3.8L I keep blowing fuse #18 (under dash fuse box) It was running great then i went to floor it and it blew. I was able to put another fuse back in and drive for a bit but as soon as I floored the fuse blew again. But this time any time I turned it to the acc it blew the fuse again. I thought it was the CCRM so i replaced that. I recently replaced the fuel pump. But even with the pump disconnected it still blows the fuse. The manual says 18 / 20a fuse / Generator warning lights > EEC pwr. relay coil. Im going nuts trying to search online for the EEC pwr. relay coil location. Any time I do a search it only gives me 5.0 not for the 3.8. Why would the manual says EEC pwr. relay coil if i didn't have one. does anyone know what my issue is or where the EEC pwr. relay coil location is. I've check the passenger side kick panel but the cord coming out isn't there but of course that was for the 5.0 diagram. Thanks
     
  2. Orange 94

    Orange 94 Moderator Staff SN95 Supporter

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    I don't have my owners manual with me currently. Generator warning lights eec pwr almost sounds like a cluster problem?
    Not 100% sure. I found this but I'm also not 100% sure its correct.

    [​IMG]
     
  3. DavidMustang

    DavidMustang New Member

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    Yeah thats the fuse box for the 5.0 though. the 3.8 doesn't even have the CCRM listed but it does list the transmission control switch but says 5.0 only. When I was searching online i also thought it was the correct one so I replaced my CCRM thinking that was it. Thank god I got a used one for only $20 does the same thing as my original. Also my cluster was replaced but like 2 years ago but even with that unplugged I still blow the fuse
     
  4. DavidMustang

    DavidMustang New Member

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    [​IMG][​IMG]
     
  5. DavidMustang

    DavidMustang New Member

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    ok well I removed my cluster still keep blowing fuses
     
  6. DavidMustang

    DavidMustang New Member

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    I think im just going to replace mustangs wire harness
     
  7. DavidMustang

    DavidMustang New Member

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    Well I have a 3.8L not the 5.0 it says 5.0 on that one. but i was checking some wiring [​IMG]
    I found out that only 3 things are hooked into that fuse 18 the instrument cluster (which i removed and installed the other spare I had and also tried it without the cluster installed) Next is the alternator its self it goes to the voltage regulator ( disconnected the alt completely still had issues) the last part is the radio noise capacitor. I was reading more into the signs and they says that if not replaced you will get a no start condition plus radio interference. I placed an order for a new one it will be here by 3pm tomorrow. we will see what happens next I guess.
     
  8. DavidMustang

    DavidMustang New Member

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    Well so far I think I found out what the problem was. It wasn't the capacitor after all. But when I went to install the new capacitor i was also checking the wire harness off the coil back and inspected the wires as far back as I could. Then noticed the one of my injector wires was exposed about a half inch all the way around the wire. So I fixed that problem and so far my mustang is running ok. Im a bit nervous to take it out on a main drag because i dont want to be stranded somewhere. But I'm going to have to do it and take that chance. But it is nice to be able to drive my mustang again I've definitely missed her.
     
  9. DavidMustang

    DavidMustang New Member

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    Ugh well that wasn't the issue car died on me had to get her towed back home. Does any one know where the unit is that generates the warning lights on your dash
     
  10. DavidMustang

    DavidMustang New Member

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    Well i'm giving up trying to figure this out and my parents are tired of me talking about it and also want me to have a reliable vehicle again. They going to pay for the cost of taking somewhere and getting repaired. What I'll do is once they figure out what it was and how they fixed it. I will update this post with all that info just incase this happens to someone else down the road.
     
  11. DavidMustang

    DavidMustang New Member

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    Well I guess I was playing around with my car a bit more before we took it in for repairs. I unplugged the Camshaft position sensor and looked at the wiring but forgot to plug it back in but when i went to crank the engine the car started up instead of popping the fuse like it usually does. Of course the car sounded and idle like crap. It then dawned on me i never plugged that sensor back in. Long story short I ended up replacing that senor. Now my vehicle doesn't blow fuses anymore but when i'm driving like before the engine just dies on me. But the good news is that i'm able to start the car right back up and starts driving it again and thats with no fuse 18 or any fuse popping. So i also ended up replacing my Crankshaft position sensor also. I finished installing it last night but since it was late I wasn't able to test my car. Just incase i did get stranded again. Ill let you know the results when I take it out this morning.
     
  12. DavidMustang

    DavidMustang New Member

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    :(:(:( Well it was working for a day and a half then died on me again. So with that tow we had my Mustang towed to the shop to get repaired. So ill let you know what the final result is hopefully soon.
     
  13. ttocs

    ttocs Legend

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    it sucks but often with electrical problems until you really get down and start inspecting/tracing wires its nearly impossible to figure out where/how/what is wrong. It can be the smallest thing, just the littlest piece of exposed copper and its all you need for a horrible gremlin. I took an electricity class back in high school where we would wire up 2-3 switch circuits complete with conduit and junction boxes for the experience. One time after we finished and it was working perfectly he got picky and pointed out that there was just a SMIDGE of copper visable under one of the twist nut connections through one of the holes punched in the junction box. When he did this he did it with his pencil which the tip grounded out to the junction box and since it was plugged in made for an EXCELLENT demonstration of what could happen if(your teacher sticks his pencil in the wrong place). The end of the pencil exploded and smoked what was remaining in a nice spark show. Needless to say you could tell by his reaction it was not planned but I have been sure since then to ensure there is NO/ZERO/ZIP/ZILCH copper showing on any connection I have made.

    I also have fond memories of watching that teacher shock the hell out of himself while trying to repair the shop ceiling fan. I say memories in the plural as he managed to shock himself 3 times in the hour we were in class with him and my buddy in the next period said he almost lost it completely when he did it again in his class.
     
  14. DavidMustang

    DavidMustang New Member

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    Thanks for your input i really appreciate it a lot. Yeah I was getting tired of trying to figure it out because I ended up using 5 tows in 1 month. I kinda wish the problem wouldnt go away like it does where you can start the car again and drive it and have no issues then boom the engine dies and wont start again or keeps popping fuses. I just hope that the car shows the signs when its dropped off at the shop. I noticed that after the tow truck driver towed me how and i parked it. My vehicle would some how start up again.
     
  15. DavidMustang

    DavidMustang New Member

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    Well I dont know how it happened but the problem was the wire harness ended up laying on my egr pipe and thats what caused the problem. I wish I would have noticed that. I should have looked all all the areas around my engine bay better than I did. But I do know over in that corner because of the A/C theres all that stuff blocking that side of the engine compartment really hard to even check your transmission fluid also. Well they did fix my Mustang and i'm happy to have it back but it cost me $486.00 plus the cost of a used CCRM that i didn't need $20 and a new CAM sensor $29.99 and a crankshaft sensor $35.99 for a total of $561.99. Now the crank shaft sensor was OEM. I'll make sure to hold on to it just incase. But both the products I got were lifetime warranty. It was expensive but im glad to have my Mustang back.
     
  16. ttocs

    ttocs Legend

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    Yea troubleshooting electrical stuff is almost never cheap just because it is a slow tedious process of tracing wires and checking connections.