Wife's G4 just had the battery light come on again after 2 years.

[Dirk Diggler]

I hope this isn't a need for a new alternator. There's no aftermarkets available at any of the big parts store so that means I'll have to take it to a dealer. It's $1000 just for the alternator at Mitsubishi.

We had the same issue with corroded battery cables 2 years ago flashing the battery light while it was driving. No issues until today. I'm hoping it's something simple like it needs a new battery. I did drop a new cheap battery in it 2 years ago.

My buddy has a code reader so I'll post what we find tonight in a few hours.

You think I should check to see if the brake lights are out when she gets back home?

[AtomicPunk]

I hope this isn't a need for a new alternator. There's no aftermarkets available at any of the big parts store so that means I'll have to take it to a dealer. It's $1000 just for the alternator at Mitsubishi.

We had the same issue with corroded battery cables 2 years ago flashing the battery light while it was driving. No issues until today. I'm hoping it's something simple like it needs a new battery. I did drop a new cheap battery in it 2 years ago.

My buddy has a code reader so I'll post what we find tonight in a few hours.

You think I should check to see if the brake lights are out when she gets back home?

Ask your buddy ( or Autozone) to check the charging voltage at the battery with the car running and accessories off. Should give you an idea what alternator is doing. Autozone will check your battery for free, too.

[Fummins]

I don't believe brake lights would have anything to do with the battery light.

The battery light will come on for two reasons. It's either overcharging or not charging at all. If it isn't charging, it'll keep running until the battery dies then you're scewed. My first guess would be the common broken wire but you should check other things first...

First and easiest thing to check is make sure you still have a belt... If you're belt broke, you're gonna have a bad time.

If you still have a belt, the next thing I'd do is finger out if you're battery is being charged or not when the engine is running. Start it up and throw a volt meter on the battery. It should read between 13.5 and 14.5 volts(when engine is running).

If it's reading closer to 15Volts then you probably have a broken somewhere in the wiring harness between the alternator and ecu.
The most common place for them to break is in the wiring harness along the top of the intake manifold. Usually near where the harness is zip tied from the factoria. Wires vibrate and chafe through, then hang on by a thread. One way to check if this is your problem(not a sure fire way) have someone sit in the car(running) and wiggle the wiring harness around. If light flickers or turns on and stays on then that's probably your problem.
Easy cheap fix. Find broken wire then repair it. Might have to splice in a little chunk oh' wire.

If it's under/not charging I'd still take a look at the wiring harness. That could be the problem too. I've yet to see a bad Mirage alternator but that's not to say they can't go bad. I'd check the wiring first before throwing a new or even a used one at it.

This post is probably way longer than it needs to be.

[Dirk Diggler]

I don't believe brake lights would have anything to do with the battery light.

The battery light will come on for two reasons. It's either overcharging or not charging at all. If it isn't charging, it'll keep running until the battery dies then you're scewed. My first guess would be the common broken wire but you should check other things first...

First and easiest thing to check is make sure you still have a belt... If you're belt broke, you're gonna have a bad time.

If you still have a belt, the next thing I'd do is finger out if you're battery is being charged or not when the engine is running. Start it up and throw a volt meter on the battery. It should read between 13.5 and 14.5 volts(when engine is running).

If it's reading closer to 15Volts then you probably have a broken somewhere in the wiring harness between the alternator and ecu.
The most common place for them to break is in the wiring harness along the top of the intake manifold. Usually near where the harness is zip tied from the factoria. Wires vibrate and chafe through, then hang on by a thread. One way to check if this is your problem(not a sure fire way) have someone sit in the car(running) and wiggle the wiring harness around. If light flickers or turns on and stays on then that's probably your problem.
Easy cheap fix. Find broken wire then repair it. Might have to splice in a little chunk oh' wire.

If it's under/not charging I'd still take a look at the wiring harness. That could be the problem too. I've yet to see a bad Mirage alternator but that's not to say they can't go bad. I'd check the wiring first before throwing a new or even a used one at it.

This post is probably way longer than it needs to be.

Thanks man I'm sending this to my friend to better help diagnose the issue. I will post an update.

[Top_Fuel]

Dirk... The last time this happened to you, it was a corroded battery cable, right?

Maybe take a look at the battery terminals to make sure they don't resemble a science experiment...

[Dirk Diggler]

Dirk... The last time this happened to you, it was a corroded battery cable, right?

Maybe take a look at the battery terminals to make sure they don't resemble a science experiment...

It'll be the first place I look. I'll pour some coke on that too if I see it.

[Fummins]

It'll be the first place I look. I'll pour some coke on that too if I see it.

Pee on it too. Or not….
Attachment 23369Attachment 23370 if all of the obvious first things to check seem good look here.^ Usually you gotta snip the zip ties(or carefully open them) slice the tape open and have a look.

Ps.
Send beer

[Dirk Diggler]

Pee on it too. Or not….
Attachment 23369Attachment 23370 if all of the obvious first things to check seem good look here.^ Usually you gotta snip the zip ties(or carefully open them) slice the tape open and have a look.

Ps.
Send beer

Will do. Thank you for that brother. I'm waiting a couple of hours for the wife to get home. She said the car started up and ran fine on the way to her job, but the battery idiot light would flash on every few minutes or so and then stay off for a while and then repeat.

[Fummins]

She said the car started up and ran fine on the way to her job, but the battery idiot light would flash on every few minutes or so and then stay off for a while and then repeat.

That sounds familiar. Keep us posted.

[Top_Fuel]

I gotta remember to clip those "zip-tie" wire harness thingys...that's just a failure waiting to happen.