dash lights works opposite

[windofire]

hey guys
i've been driving my mx allmost 12000 km's since i swaped the ze in and the only problem so far has been a wheel bearing

BUT now my car i acting wierd. when i put the keys in the ignition and turn the key the battery, abs, light and oil lamp doesnt turn on, but when i start the car they do and i can see on my radio that the voltage is dropping slowly (it has a built in voltage gauge). besides that i also hear a humming noise for a few sec when i turn on ignition, it sounds like its from an electric motor in the engine bay but i cant remember if its normal

it did it yesterday too and suddenly those lamps turned off and was acting normal again till to night. i've checked the fuses, ground wires and such but it seems okay. any suggestions?

i will upload a video tomorrow so that you guys can see what i mean.

[Nd4SpdSe]

when i put the keys in the ignition and turn the key the battery, abs, light and oil lamp doesnt turn on, but when i start the car they do

That should be normal. On ACC they shouldn't' be on, but your radio would work, but on ON (and of course after you start it), all the lights would go on than turn off. All should turn off if the motor is running, but if you just have it on ON without the motor running, you should get some lights, like Oil Pressire and maybe battery, I can't remember

I can see on my radio that the voltage is dropping slowly (it has a built in voltage gauge)

What you mean? What voltage does it start at and what voltage does it drop down to? This happens after you start your car?

[windofire]

The voltage starts at about 12v without the engine running and when its running it will slowly drop.

Heres a vid to see for your self

https://www.youtube.com/watch?v=p7SrXeV ... ata_player

[windofire]

i've just checked the codes, theres a code 17 and a code 25

[Redline322]

I dont think I would trust voltage from a head unit unless it is verified just in case. The best way to check is to start the car and use a multimeter on the battery. With the car running, it should be in the 14v range. Check to make sure your alt belt is tight and that all the connections to the alt are good. The buzzing sound usually relates to a bad ground somewhere.

[windofire]

the voltage from my head unit is only 0,1 or 0,2 off, i've checked it with a multimeter
my battery was tested yesterday and the course of those fault codes has been corrected.
it sounds like that buzzing sound is from somewhere below the battery or below brake booster but in the engine compartment and i can feel it vibrating the floor when sitting in drivers seat

i was going to check my alt. tomorrow, but how is the best way if i dont have a amp. meter up to 90A?
if my alt. fails, is there any common courses to that?