turbostd

Ok I have a good one for you I have a 92 lx that for some reason or another don't want to charge. The weird thing is that the light on the cluster doesn't even come on at all not even when you turn the key on before starting the car. Here is a list of what I checked/replaced

Alternator
Fuses
Bulb in cluster
ECU
engine harness

Now the last 2 things I can think of are the main relay and under hood fuse box but i don't really think they have anything to do with it. Any other ideas before I get mad and scrap the car??

88dx

Battery? U checked the alternator output with a volt meter?

turbostd

battery is new and output from the alt is 0v

turbostd

Just got back from the junkyard. I got both fuses boxes and a main relay i also picked up the driver side window switch and door lock switch all for $10. I love my local yard awhile back I got a full z6 swap for $200. My car is sitting at a friends house so once he gets home im going to start replacing stuff.

Cray91

Is that the output at the alternator? Maybe you got a bad alternator from the store, it happens.

turbostd

Thought that too had it checked and it was good, got another anyway still no go. Its like the ecu isnt turning the alt on for some reason.

b18.

That alternator is going to turn and give charge no matter what that ecu says so long as those diodes aren't fried. Are you saying that the car doesn't come on at all, i.e. no electricity anywhere? Or do you mean to say that the alternator isn't charging the battery but the car runs and can start, like the thread title implies?

Have you checked continuity in the battery cables?

Through the fuse block?

Through the ignition switch?

Get a multimeter if you don't have one.

turbostd

Car runs and drive fine untill the battery dies. The battery light doesn't come on AT ALL not even before you start the car or disconnect the alt. I just found a good diagram of the charging system so i am going to go check all the connections.

b18.

Measure resistance in the battery ground cable and through the fuse block.

Also you can do a running test of battery load, measure the change in voltage when you turn the car on, if anything any service station will have a machine to test the draw and the output of the alternator.

A quick test to see if your getting current from your alternator is to measure the voltage while running, it should be anywhere around 14.7-16volts with a good alternator charge. Also check from the output wire to battery ground.

I doubt it's the main relay honestly, usually it'll go all together, unless there's break at the connector to it or something freak like that.

turbostd

Yay Its fixed I had 3 bad alternators in a row wtf? Im going to start looking for a low millage used one cause these new ones suck note to self never assume a new part is good.