More wiring fun...

Discussion in 'Gen 1 & 2 - Electronics & Audio' started by Fordlover96, Nov 5, 2016.

  1. Fordlover96

    Fordlover96 SHO Member

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    Okay, I'm gonna try to explain this one as best I can.

    I have an aftermarket alarm and remote starting system in my SHO. The remote start portion isn't functional anymore. I brought it to the place who put it in and they told me system is seeing power from the brake switch and won't allow it to start.

    Sure enough, the ground wire (r/lg) running to the brake has about .27 volts with key off. Key on it jumps to about 5.

    Is there a short somewhere?

    I tired pulling all the fuses and only one made a difference. Fuse 1. Which handles the brake lights, cruise control, and turn signals.

    Only other thing is that the cruise control isn't functional. Idk if it's because it uses the same brake switch and it's seeing power too or if it just doesn't work.

    Please and thanks guys! It'd be great to have remote start again this time of year! Lol
     
  2. Fordlover96

    Fordlover96 SHO Member

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    Okay. Update.

    I just unplugged the cruise control servo in the engine compartment. The voltage reading on that wire dropped down to zero.

    I went to try to turn on the car on and the wire gets 5 volts as soon as the key is put into the run position. It shouldn't have any power unless the pedal is pushed.
     
  3. kevinspann

    kevinspann 87 Octane

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    I'm not sure if it will help, but I'd replace the switch on the master cylinder that is supposed to deactivate the cruise as well. Ford recalled a lot of these for being a potential fire hazard, even with the car being turned off.

    At the very least, unplug it instead of the cruise servo and see if you get any changes in voltage - that way you can isolate the issue.
     
  4. Fordlover96

    Fordlover96 SHO Member

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    I actually unplugged both that pressure switch and the cruise servo.

    Unplugging the servo dropped the voltage to 0 but it goes right back up to 5 when the car is turned on.

    Also that pressure switch it brand new. Along with the recall kit.

    There's short in ground somewhere I think. Does anyone know where the major grounds in these cars are? Thanks!
     
  5. Fordlover96

    Fordlover96 SHO Member

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    Bump...so I just discovered that the brake lights are faintly on all the time. This doesn't really bother since all the bulbs are LED. But I'm pretty sure that means a short. You guys have any ideas where to start?
     
  6. Fordlover96

    Fordlover96 SHO Member

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    IMG_5196.JPG IMG_5197.JPG Okay so another bump...

    Did some research in my EVM and here's what I found. The red/light green wire that is getting voltage runs to a couple different things. The computer, cruise control, multi-function stalk, etc. I've already tried unplugging the MFS and Cruisecontrol servo under the hood. No changes. Where should I go from here? Main computer?
     
  7. luigisho

    luigisho SHO Member

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    That's a place to start if you have a spare or someone you know can swap to check. However I would first look at a faulty brake light switch near the pedal first. I would check the grounds in the circuit and that the housings are good. I hate aftermarket alarm and remote starts for just this reason. Tracking electrical problems gets really sketchy with all that mess wired in.
     

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