2002 Ford Mustang Electrical probs

gvalenzuelagvalenzuela Member Posts: 8
edited July 2016 in Ford
Hey guys, I have an automatic 02 mustang gt that I'm working on. Got a few electrical problems. First, the abs fuse inside the car blows as soon as I put a new one in. 2nd, in the fuse box under the hood, the audio fuse and the cig illumination fuses also blow as soon as I put a fuse in. And third, for some reason, the driver side speaker and window won't work. Also, this one is odd, but the wiring behind the lower panel on the driver side has many clips as if them wires were tapped into??? Not sure why or what the purpose was. Maybe that has something to do with the problems. Also the car is equipped with the machine 1000 audio system in the trunk, but those woofers also DON'T WORK.... Can someone help please???


  • gvalenzuelagvalenzuela Member Posts: 8
  • steverstever Guest Posts: 52,454
    edited July 2016
    At first glance it sounds like a rat's nest of electrical issues related to the wire tapping. Wonder what that was about since it sounds like you have the OEM stereo in there. Security system? Remote start?

    Dunno, not a mechanic, but something (things?) is shorting out. Tracing the shorts can be a bear. (youfixcars.com) You can get wiring diagrams at bbbind.com for free (and AutoZone too I understand) if needed, but so long as you keep track of the wire you are testing, that may be enough.

    Check the connections for corrosion too - that's not uncommon with an older car.

    I *think* the wiring may be easier to check than the components but something like a bad switch could be shorting out too. Here's a Mustang specific link that may help.

  • thecardoc3thecardoc3 Member Posts: 5,569
    Imagine taking on problems like this as your regular day job, especially when the overwhelming opinion was that we were just supposed to know what was wrong and every time you turned around someone else was trying to devalue it. The links above are decent examples of old school basic strategies, you really should see how we teach techs to approach this kind if work today. Here is an example.

    The first thing to do is pick one of the failures and concentrate on it, trying to solve all of them at once only makes the task more difficult. Lets use one of the failures that result in the blown fuse as an example. You need to print out the schematic and highlight the parts of the circuit where a failure could result in the fuse blowing.

    Now the high tech approach is to substitute the fuse with a headlight, not a circuit breaker as described in one of the links. The headlight will allow the circuit to be powered up, and limit the current flow in the circuit to a workable level. Keep in mind that a headlight is appropriate for some circuits, but could flow too much current for others, so in practice we have substitute loads of varying current draw. The radio and lighter circuits for example would have me use a smaller lamp such as an 1156 brake light bulb. We choose our substitute load based on the fuse rating, fifteen amps or more the headlight is a good choice while for circuits under ten amps smaller lamps are more appropriate. The next thing you need is a way to measure that current flow, and most multi-meters can handle up to ten amps on their current settings. But there is a problem with just using the multi-meter. The meter has to be installed in series for it to measure the current. That's a problem because you need to be able to test the circuit at different strategically chosen points. To do that with the multi-meter you would have to open the circuit and attach the meter in between for each measurement and that would be (could be) very labor intensive, so a better choice is to use a tool like the low amps current probe.


    Prices on these tools have dropped dramatically in the last ten years. This tool cost me more than $400 when I got my first one back in the late 90's.

    Now the rest of the routine is to use the amp clamp to measure the current flowing in the circuit at strategic points based on accessibility and then when you isolate the area of the circuit failure, only perform the most labor intensive efforts right there in order to actually find and repair the failure.

    Once you find and solve the first problem, then you choose the next one and work through it with the same concentrated approach. Then the next one, and then repeat until you have solved all of the issues.
  • gvalenzuelagvalenzuela Member Posts: 8
    Thanks for the input guys. I followed the wires for the window motor and juggled them and there's a short. It would work when I moved the harness. As for the audio, I've figured out the it's the driverside rear speakers that aren't working also.

    NEw subject. When I got the car the computer was burnt out. I ordered another one that already comes flashed and programmed to the vehicles vin#. I installed it, but the THEFT light flashes when I turn the key, it cranks, but won't start. The theft light flashes really fast. I had a locksmith come by yesterday to reprogram the keys I have to the new computer. He tried programming both and neither of them worked. The car does have the PATS alarm system. And the company I ordered the computer from flagshipone.com does say that the keys might have to be reprogrammed. Locksmith said that the chips in both keys might be bad since PATS would just boot them out. He said that he could make me a freshly cut PATS key with a new chip and program that one and maybe that would work.

    So after last night I've been reading blogs and watching videos and just doing my own research. And I noticed that if the alarm is on active, and the door is opened with the key and not the keyless entry remote, and you try to start it,, PATS won't allow the vehicle to be started? I can tell the alarm is active because the theft light flashes even when the key is out of the ignition. Problem is, I don't have a keyless entry remote. So I ordered one and I'm hoping that it works.

    Any thoughts on anything else that could cause the PATS to be acting up? I've also read about the transciever? 
  • gvalenzuelagvalenzuela Member Posts: 8
    Still nothing with a fresh, programmed key.
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