Alternator fuse

MICHAEL STAIR

MEMBER
1997 MITSUBISHI PAJERO
V6
4WD
AUTOMATIC
350,000 MILES

Hi, trying find out a problem with my car. I was driving along doing about 90 km a hour, when radio stopped working then the A/T light was on.S o pulled over to check all seem okay. Turned car off then couldn't start it. All power gone. Got it jump started and limp it back home. Speedometer wasn't working or blinkers gearbox wasn't changing gears. I found a 100amp blown, alternator fuse it said. Put another fuse in got battery charged. Car started sounded normal except no A/C, windows not working or radio. Took it for a drive gearbox wasn't working probably. Limp to repair shop. They said gearbox stuffed. Got a second hand one still not changing gears. Fuse blown again. Any ideas would be grateful. Before the repair bills get any higher.

Saturday, March 2nd, 2019 AT 3:44 PM

3 Replies

JACOBANDNICKOLAS

MECHANIC
110,176 POSTS

Hi and thanks for using 2CarPros.

First, please understand this specific model isn't available in the US. However, I have technical information for the Mitsubishi Montero which is to be the same vehicle.

The fuse that keeps blowing is a concern because if how much current needs to flow for it to blow. With that in mind, there has to be a direct short from the power supply.

As far as the transmission, it makes no sense to me that a blown alternator fuse would cause transmission issues. However, if there is low or not enough power, electronics will begin to fail which is what I believe you originally experienced. Regardless, once the power is restored, the electronics should return to normal. That leads me to my next thought. Since the speedometer wasn't working, that tells me the output speed sensor wasn't working. The speed sensor is responsible for making the speedometer work. If it fails, the transmission will most likely not shift correctly. Is that what was happening?

With all of that in mind, and the idea that other things are still not working, I am going to first suggest you check the fuses related to the components still not working

Next, on my schematics I see a 100 amp fusible link for the alternator. See picture 1 Is that what is being replaced? If it is, has anyone checked the alternator itself for a short?

If you lose power from the alternator once the vehicle is running (blown fusible link) there will be electrical issues until the battery is run dead.

Let me know.

Joe

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