Electrical issues after alternator replacement

CHRISTA DICKSON

MEMBER
1998 LEXUS GS 300
6 CYL
2WD
AUTOMATIC
200,000 MILES

So my alternator went completely out recently and has been replaced a few days ago with a refurbished one. However, every since it quit running I have some weird electrical issues that I can't seem to solve. The interior dome lights only now work with the car on when the should turn on even with vehicle off. I checked fuses all good. Also, now the stereo wont power on unless I twist the constant (red) and accessory (yellow) wire together. Which is not the correct way. I had it ran and and powering up correctly with wires separated before so I don't know I know now why it will not power on with wire separated and correctly ran. Little lost here gave check wires of course and fuses.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,758 POSTS

Welcome to 2CarPros.

I need to get a better understanding of what has happened. My biggest concern is that there are wires needing twisted together to make the radio work. Is this an aftermarket radio that was installed? Looking through schematics, I see no red or yellow that would work in conjunction with the radio power.

Do me a favor. There is a 10 amp fuse behind the right kick panel. If is for the dome light and should provide power at all times. Check it to make sure it is good. (See Pic 1) Also, pics 2 and 3 show the passenger side fuse box location and which fuse to check, number 13.

If the fuse appears good, confirm there is power at the circuit. Here are a few links you may find helpful:

https://www.2carpros.com/articles/how-a-car-fuse-works

https://www.2carpros.com/articles/how-to-check-a-car-fuse

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/how-to-check-wiring

Let me know where the red and yellow wires which make the radio work are coming from.

I will watch for your reply.

Joe

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