Losing all electrical on my 1999 Jimmy

Basic automotive electrical testing with a volt meter is how to fix ! Find a wiring diagram and componet location chart - connector's wire harness , power and ground locations etc.... Diagnosing Turn Signal Problems http://www.bbbind.com/free_tsb.html Could be the turn signal switch , lose connection somewhere . Ground problem .

run the fault codes with a scanner to determine where the faulty sensor is

Check for trouble codes.

check the fuel pressure reg. valve n see if it still holding pressure if not change valve

do you have a check engine light on? if so my next question is after losing power does it ever seem to pick up again while running? if the answer to these questions is yes then you may just have an o2 sensor goin bad or something of the sort. if that isn't the problem many garages have what is called a back-pressure tester that can be hooked to you exhaust to see if the converter is clogging. hope this is of help and best of luck! (by the way if you do have a check engine light on i would stop at autozone, advance auto, etc to have them scan it since they do it for free)

Wow. Unless you are an electrical guru, i would steer clear of do-it-yourself on this one. Take it back to where you got it, unless no warranty. Otherwise, find a good shop that specializes in Euro cars. There has to be a short somewhere, otherwise it wouldn't be blowing fuses. With all the miles of wires in the car, it could be anywhere. Sounds to me like either: 1. it was in a crash and repaired poorly
2. mice have been chewing on wires
3. water damage

Sounds like a bad wire somewhere. I dont know with your particular vehicle, but some vechiles wiring leads into eachother for alot of things. If a wire is being grounded out this could cause the loss of the electrical units connected on the wire. Just a guess, but I would check with a mechanic to find out if there are electronics in your vehicle that work off of eachother. Explain what things come off and on when you lose the power to what you listed. You use the word random, so my guess would most likely be a wire being grounded out somewhere to cause this. Hope this helps!!

did you change your thermostat probably stuck closed

have them check the crankshaft sensor. sometimes they crank and when the water hits them the car dies out. its quite common on the 3.0l

I have the same problem, the brakelight switch is constantly becoming lose, there is no solution, but to wire the switch in, so it cannot move, welcome to America.