Battery on my 1998 Maxima keeps going dead

[Tomm1]

Dealer said I needed a new battery and replaced it. Battery kept going dead. Dealer said I needed a new alternator and replaced the alternator. Battery kept going dead. Dealer said the new alternator was bad (something about a "fuse" in the alternator blown?...doesn't sound right but that's what they said). Dealer replaced new alternator. Now dealer says that there is still an electrical drain. They "think" it is in the dome light (although the dome light is off) and in the indicator light for the alarm system. They now want to change the body control module, which they think will correct the problem. I asked them to stop changing things until I can find someone who can troubleshoot the problem. I have noticed that the alarm system indicatro light stays on steady since the problem started (before the problem started the alarm system light blinked). Could it be the body control module? If so, where is it located and about how much does it cost? Can I change it myself? Thanks!

[Beancooker]

I'm stumped. I briefly looked through the FSM's and saw nothing called the "body control module". I'll keep looking for ya!

[Tomm1]

Thanks!

[nismo1219]

we were told the same thing about a "body control module" but with my g/f's '96 sebring. we got tired of spending money fixing the never-ending problem-saga so we got her the altima she's in now!

however, we were told that the "module" would cost about $1,500 for her car and it then labor to be programmed! PLUS - it could only be done by a "stealership!!"

but, like i said, we solved that problem with the altima! cant go wrong w/a nissan!

[TheKon]

Not all cars have a BCM. I know for a fact my impala does and they're a total ***** if they go bad. Instead of having switches relays controlling the car many car manufacterers (mostly american) use BCMs. A bad BCM will trigger a Service Vehicle Soon light not a Service Engine Soon or Check Engine light. They communicate with everything from head lights to windshield whipers. And they match up directly to your car any only your car. So it's not something you can run over to the junk yard and pick one up. You can get one from a junk yard but it will have to be programmed....hence why they're so expensive. Look through the manual of your security system and find out what a constant light means. That might tell you exactly whats wrong. That little LED won't run your battery dead. I had a stiffening capacitor in my impala that refused to shut off and that had a good 10 or 12 LEDs constantly flashing moving blinking etc. all night long...started up like a champ in the morning (except for when the bat. took a **** on me and died a few weeks ago (it was 5 years old time for a new one anyway...well after the capacitor was replaced anyway). One other thing...try checking the wiring from the battery to the chassis...this is your ground. If the connection is poor, your battery isn't being recharged. Also make sure the wire from your alt is properly connected to your bat. It's sounding like a bad connection from the alternator to the bat. Battery to starter sounds like its okay and the alternor seems to be connected to the rest of the car fine...if you can jump the car. I've never seen the wiring for the maxima but that could be your culprit, but I know my starter isn't grounded there's a wire running straight to the negative terminal.

[Beancooker]

Okay, after further investigation, I can not find anything about a BCM on our cars. There is an ECU (aka ECM) that controlls all electrical components, but this is something that can be interchanged between cars. As long as it is from another Maxima of the same year, you should be fine.

Do me a favor, and ask the dealer, in what section, and on what page in the FSM does it show the BCM. I'm really interested to see this.

[TheKon]

They're probably just making stuff up...

[maxhopper]

There is in fact a BCM (Body Control Module) for this vehicle.

As the BCM monitors many aspects of the vehicle, ask the dealer to try a BCM out of their parts inventory, or used car inventory to see if, in fact, this is the problem...this is not a part you want to pay for if it isn't the cause.

Another possible cause is an electrical fault/short ; which could take (up to)hours to trace.

[A.Tech]

The only thing I can think of is a parasitic load. ( it is like the electrial drain they mentioned) or a bad ground can be the cause. Take it a place that acutally knows enough about electricity on a car and what could be making the load.

Do you have a system in the car?

[A.Tech]

About the bad connection to the battery from the alt. I bet they checked if the Battery is getting 14.8v right away(Well they should of). I mean that is the first thing I check when I put a new battery in or an Alt.