SeedyROM

SOLVED: The issue ended up being the driver's seat controls (short/failed board). Similar thread here showing it's happened before. Also, here's a thread for removing the seats without power/ability to slide them. Thanks everyone, Max.org rules
__________________________________________________ __________________________________________________ _______________

Appreciate ANY input here. I've done some searching and found some great info that may apply but I have some clues I'd like your input on so I can track it down.

Background: Get car washed three days ago, normal place, nothing fancy. Later in day I lose power windows/doors. 40a under hood fuse blown, replaced and blew again. Thinking water may have got near/in the fusebox, I removed what I could, blew out with air, let sit for two days and then reseated everything. New fuse, blew again (damn things are $5!).

It's a longshot but I do remember when they were drying off my car I kept hearing what sounded like my horn beeping like I locked the door. Since the keyless entry/alarm controls the doors, I wonder if that side of the system is the culprit? Maybe I can pull the alarm fuse, replace the window fuse and see if the windows work? Or maybe something else? Electrical is the one thing I really hate but I'm open to ideas!

SeedyROM

Additionally, I found this great thread from a guy who went through similar issues and tracked it down to the wiring under his seat, which shares the same fuse. Nowhere does he mention the alarm system though, so before I go tearing things apart I wanted to ask.

Normally I'd just yank my seat off and check but it's stuck all the way back with the dead fuse and it's a pain in the butt to remove if you can't get to the bolts.

TunerMaxima3000

iTrader: (4)

Hey Seedy, long time no see!! Hope both the whips are treating you well otherwise.


This fuse?



I'm not sure where that circuit breaker is, but you should check it.

TunerMaxima3000

iTrader: (4)

The next step though IMO is to pull the sub-fuses for the parts listed.

SUNROOF
SEAT
AUT/DP (what is this?)
WINDOW
DOOR LOCK
KEYLESS


I think I got them all here:




Here's the "legend" for the fuse location. First picture is the UNDER HOOD. 2nd is the In-cabin I think (the one by the pedals)






Once you have pulled all those fuses you can reinstall a new fuse in the 40 AMP position that is blowing. Test it. If it doesn't blow, then start systematically installing the fuses you had removed. Take your time, leave at least a couple minutes after each one is plugged in and make sure the 40 AMP fuse is NOT blown yet.

Once you install a fuse and the 40 AMP blows, you'll have a more precise direction to go (you'll know exactly what sub-circuit is potentially at fault, and can keep narrowing down from there much faster)


Alternatively, if the 40 AMP fuse blows with all the sub fuses disconnected, it's probably something very close to the fuse itself, before the 'sub-system'

So there's the next step mang. Post back your result and we will go from there


(It's odd/unlikely that the 40 AMP fuse would blow because of one of the sub-circuits, ie: seat motor, etc. These items are in the sub-circuit for just that reason, they are protected by fuses that should blow before that circuit breaker ever trips, let alone the actual 40 AMP fuse blowing. But one step at a time, let's find that out for sure. I've seen 5 amp fuses melt together and flow way more than they are supposed to, so we can't rule it out.)

SeedyROM

Tuner! Great to see you man and yeah, things are well outside of this issue. The Max has been a dream these last two years...so glad I stuck with Nissan again for my daily.

Anyway, yes that does appear to be the 40a I'm having issues with and this is some great info! Right after I was done typing it all out I thought to myself "damn, should have bought the Maxima FSM" and then you went and grabbed everything I could have needed. Great call about the subsystems usually popping first (that's the point isn't it?) but I'll still check them just to rule out any oddities. If it still pops, I'll start tearing the fuse box apart and looking closer to the source.

Nelsito65

My son's 2000 was recently left without control on the power windows, locks, sunroof and seats. The key fob would not work either. He said that he heard a "click" after trying to adjust the driver's seat and all those features stopped working after that. That same fuse you are blowing was blown on his car. After reading about the symptoms described, I decided to swap the master power window control module on the driver's side door. Then I replaced that fuse and everything has been working so far.

rebelhell

iTrader: (1)

For future reference...it's free right here.
http://www.nicoclub.com/FSM/Maxima/

SeedyROM

Thanks for this, I'll keep it in my back pocket if I can narrow it to that. I read that's worked for a few people and they can be found for under $75 on ebay. With any luck it wont come to that.

Good lookin' out. Much better than the online one I bookmarked a while back.

TunerMaxima3000

iTrader: (4)

That's what I use for my Maxima and Infiniti.

DennisMik

iTrader: (2)

It stands for "Automatic Drive Positioner". It is the power seat in Nissanese.

Those Nissanese things are usually in the alphabetical index. But not always.

DennisMik

iTrader: (2)

I'm trying to think about this using logic. Please don't flame me for this.

For a sub circuit that has a 10 amp fuse to blow the 40 amp main fuse and not it's own 10 amp fuse does not make sense.

The circuit breaker is supposed to operate to prevent that 40 amp fuse from blowing when you keep your finger on the window or seat switch after it has reached it's limit. The circuit breaker could be bad and not protecting the fuse, but I can't see it being the cause of the fuse blowing.

The circuit breaker is buried under the dash. It is back by the firewall, roughly behind the in-dash fuse panel.

The circuit breaker, besides powering the sub-circuits, goes direct to all 4 power window switches, both power seat switches, the sunroof motor (not the switch) and the SECU module for the door locks and keyless entry.

The windows are the only things that could have contact with water, the other things are inside the cabin.

Have you ever taken the driver's door panel off for something and removed the plastic sheet behind it and left that plastic off? This could allow water from rain or the car wash to splash on the power window switch. Or any of the other doors for that matter. You can pop the switches out of the door panel without removing the door panel and unplug the wire harness and see what happens.

SeedyROM

Yep, sounds like the subsystems should catch first but I had found two other threads (one above) where the issue was a short in a harness and it still blew the 40a for those people...even though that doesn't really make sense. You and the above posters are right that I should be able to narrow it down easily if one of the subsystems was really causing it so I'll just yank those to start and work backward to be safe.

Regarding the window/door, I've never had them off but the prior owner may have and for all I know the carwash/water was coincidence. Good to know about popping them out, that'll be one more thing I disconnect just to cover all the bases. I just need to find some more 40a fuses locally so I can get started today.

TunerMaxima3000

iTrader: (4)

Nissanese. Thanks dennis!

Well that's good info!! Makes sense for them to have the circuit breaker on a window circuit, didn't think of that. Nice deductive reasoning.

As for the "logical thinking" we both know that electrical stuff tends to defy logic, despite the numerous safe guards and 'reasoning' we place on it.

There could be a corroded connection around the 40amp fuse and it's wiring before the sub-circuit fuse protection, and the draw is being placed from the sub-circuit (fused) side. However the draw is only 9 AMPs, lets say, and the connection is bad at the 40 amp fuse area, the power has to 'jump' that bad connection to supply (get to) the 9 amp load in the sub-circuit.
This causes a spike in amperage at the 40 AMP fuse that pops it, before the excess amperage can ever be delivered to the 9 amp load demand in the sub-circuit.


This is obviously a silly possibility, drawn up mostly out of fun, it might not even be possible, I don't know.
What I DO know is that electrical stuff defies most logic, even for those with extensive knowledge about it (which I don't have). So what may seem illogical to me may be easily explained by someone who knows more about it.

Electricity is ****ing complicated.

SeedyROM

My local parts store didn't have any more 40a and the Nissan dealer in my city closed up shop so I'll dive into this Monday and report back. Thanks again all.

TunerMaxima3000

iTrader: (4)

Junkyard is your best plan, 5 Fora bag full of them
Common fuses, especially on any Nissan you see from an old 300zx to the new Maxima

SeedyROM

An update...and the plot thickens. I found two more fuses locally (I'll try junkyard next, good tip Tuner) and here's what happened.

Test 1:
-Disconnected all six of the above listed subsystems (fuses 1, 9, 10, 13, 57, 61).
-Popped in a new 40a fuse under the hood and it did not pop initially. I waited two minutes, turned the car off/on. Fine.
-Plugged in fuses 1/13 which control stuff in the car that has been working the entire time (radio/dome light/etc). Fine.
-Then 57/61 which are labeled as horn/keyless which also always worked (well, the horn and alarm did but not the door locks obviously).
-#9 went in fine and says "seat heater" but I don't have one so who knows. 40a hasn't popped at this point but locks/seats/windows still do not work.
-Finally I plugged in #10 which is labeled as "Elec Parts" on the fuse cover. This finally popped the 40a(!) but none of the subsystem 10a fuses blew (including #10). This should have meant I at least narrowed it down and I was happy but it didn't last.

What I did next was pulled all six subsystems again, put in a new 40a hood fuse and this time I disconnected all four power window/lock mechanisms in case I had a short there. Then things got weird.

Test 2:
-Plugged in fuse #10 (Elec Parts) but none of the other 5 systems and immediately checked the 40a. Fine.
-Tried the seats first, nothing.
-Plugged in windows/locks one by one and tested. None worked. 40a fine.
-Tried the seats again for the hell of it and THEY WORKED.
-Immediately checked the 40a, still fine.
-Tried the seats 1 minute later and they NO LONGER WORKED. 40a fuse still fine though...argh!
-Just in case I had a bad 40a fuse, I swapped it with a working Nissan factory fuse from the radiator fan. Exact same issue...doors/windows/locks still don't work but it doesn't pop the 40a! WTF!?

At this point something weird must be going on because all these fuses are fine now, mysteriously. And why did my seats work randomly and then stop? Maybe it's the circuit breaker freaking out and delivery power sometimes, sometimes blowing the 40a, sometimes not? I finished by installing the remaining 5 subsystem fuses and tried all systems. Nothing changed, nothing works and the 40a is still fine. I still removed it to be safe and finished for the night.

I get the feeling I'm at the point where I might need a professional to look at this but I'm open to ideas. If the circuit breaker was something easy I'd try it myself but I heard it was behind the dash and that sucks. Sooooo....what do you guys think?

DennisMik

iTrader: (2)

I would like to try another circuit breaker. It's not doing its job of protecting the 40 amp fuse. It's acting like a piece of wire and not opening the circuit. Maybe it does work intermittently and the contacts inside are touching the case and causing the short. I'm skeptical on this because on the 4th gen, the case is made of plastic and I'm guessing that it is the same circuit breaker.

I know the circuit breaker is not up front and easily accessible. I don't know exactly where it is on the 5th gen, just the general location of "It is back by the firewall, roughly behind the in-dash fuse panel". I'll go stick my head under the dash of my 2000 and see what I can see.

DennisMik

iTrader: (2)

I located the circuit breaker in my 2000. It isn't that bad to get to and is is 100 times easier than the 4th gen circuit breaker. Also, it is not the same as the 4th gen one. The 5th gens use breaker part # 24330-C9900, approx $25 + shipping on-line. Sounds like a junkyard part to me. The part number is molded into the plastic case of the circuit breaker.

To get to the circuit breaker, you will be working in the driver's side footwell. Remove the section of dashboard trim that is below the steering wheel. Then move your body towards the center of the car and look a little behind the fuse panel and towards the side of the car. You will see a block of white plastic with what looks like a gray relay on it.

To remove it, there is a white tab on the side towards the center of the car that you have to push in and then pull the circuit breaker out of the white block.

SeedyROM

Dennis, that is awesome. Thanks so much for looking into that for me. I figure my '02 is the same so I'll cram my head under there after work and see if I can grab/replace it.

I'll report back once I get my hands on a new one. Never ceases to amaze me at how helpful the Max community is...you guys rule.

DennisMik

iTrader: (2)

We have been discussing "sub circuits" of the 40 amp fuse. We are wrong. There are no sub circuits. That 40 amp fuse is the power to the motors for the windows, seats and sunroof - period. What we have been calling sub circuits are independent circuits that control those motors, not power the motors. None of the fuses for these control circuits get their power through the 40 amp fuse.

Unfortunately fuse # 10 controls a bunch of things, including the windows, sunroof, seats and door locks. Fuse 10 controls everything that gets power from the 40 amp fuse plus more things. Fuse 10 blowing doesn't eliminate anything because it controls them all.

I'm beginning to wonder about the master power window switch in the driver's door as suggested by Nelsito65. It is a complex microprocessor controlled device that runs all the windows and door locks. It even controls the step lights in the doors that come on when you open the doors.

TunerMaxima3000

iTrader: (4)

x2, wow Dennis, that's an epic reply my friend. Someone needs to give you an award.



OKIE-DOKIE. Along with checking the circuit breaker, I'm kind of scratching my head. I don't have a lot of time unfortunately but there is 1 thing I really want to know.

Why do none of the sub-circuits list the power seat? The only place I see it is directly under the 40 AMP fuse and circuit breaker in the power layout I posted.

When I get time I want to dig through the power seat section and find out exactly how and where it gets power and ground, etc. Especially because of your peculiar experience with the seat not working.
I'm also wondering if I've laid it out right, those could not be subcircuits of the 40 AMP fuse at all. I'll check later.

Now a couple questions regarding your post:

1. Did you try both seats or JUST the driver seat? The driver seat motor is known to fail on this car, perhaps if it's failing or failed a certain way it's providing an intermittent direct short that could have went away by simply operating the motor.

2. When you tried the seat(s) with the power window switches removed, it can be reasoned that they didn't work because the switches were out. Nissan ran a lot through the main Window switch and uses it as a primary controller through the BCM. If the seats are linked into the BCM then it makes sense.
The fact that they started working then stopped again, I wouldn't focus a ton on. Could be something else that we're unaware of, like power to the seats for a timed period while doors are open, then power cuts off in case you forget to close a door fully (to save draining the battery).

However as mentioned, the fact that the seat isn't listed in the sub circuit, and the fact that you had that strange issue, and the fact that there's motor involved all make me want to know more about the circuit and possibly do more testing on it.

For now, before or after doing the circuit breaker, if your seat is in the proper position, reach under the seat and disconnect the plug to the motor. This will be hard to do, but possible. Maybe do a Resistance (OHMS) check on it with a multi meter to make sure it has decent resistance.

One step we may go is to create a short at that motor's wiring. This will tell us what effect a direct short at that location would cause. I would prefer not doing this if the seat motor is connected to the BCM though, so I want to know that first.

TunerMaxima3000

iTrader: (4)

Edit: Very nice Dennis found out the answer before I even checked or finished my post Thanks dude, good spot!

SeedyROM

What you're saying about the subsystems makes sense but as far as the culprit being the master power window switch, haven't I eliminated that with Test #2? I had the window switches all disconnected with a fresh 40a and the seats still didn't work. Or maybe I'm missing something?

EDIT: I just read Tuner's post so maybe there IS actually something seat related in the window switch area so it could be the cause. To answer his questions: 1) only have driver's side power seat so couldn't test others and 2) seats are all the way back and difficult to get under. I'll try the disconnect idea.

In the end though, maybe my best course of action is to get the circuit breaker first (easy to do, cheap at junkyard), run out and try it and if that doesn't work, go back in and grab the window switch?

SeedyROM

Back from the junkyard with another update.

Got new relay/circuit breaker and with everything attached (all fuses/windows), I put it in and tried the seats. Immediately blew the 40a fuse. So it seems it's NOT the breaker. I was not able to find a power window master switch at this junkyard though.

Anyway, I got more fuses so I re-tried a few things to get better data:
-Removed power window master switch (PWMS) switch and tried new 40a fuse. The seat works for about 15 seconds with ignition off.
-Tried the same test again with the PWMS installed and no seat movement at all. This might be bad data though because I notice that it's VERY flaky if I get the seats to work. It seems that if I remove the relay and replace it, I get the seats back (15 seconds worth) 2 out of 5 times. They never work back to back, ever...like it needs to "reset". So nothing is conclusive just yet...

Now interestingly enough I noticed something about the circuit breaker/relay. It's getting HOT like there's a draw. It does this even with the PWMS removed (I did have the other three windows attached though). So right now, the only thing I can do without getting more parts (PWMS) is remove the seat and pull all the harnesses and test one by one to see if I have the same problem I linked in the second post.

TunerMaxima3000

iTrader: (4)

Is this even possible? Didn't know that any maximas only had one power seat!


Either way it sounds like you have a motor/wire issue with that seat. Time to unplug it and test resistance.

DennisMik

iTrader: (2)

The power seat has nothing to do with the master power window switch as far as I can tell. It is an independent feature.

The power seat is listed under 2 of our so called sub circuits. Remember that AUT/DP under the 40 amp fuse? You will find AUT/DP under fuse 10 and 13.

With all this new info, I have to go back and examine the wiring diagrams.

SeedyROM

SOLVED: It WAS the wiring harness under the seat causing the issues. I guess it wasn't water from the carwash but maybe the attendant trying to move my seat that was the final straw.

It figures it was the first post I found but I didn't check it because the Maxima seat is a nightmare to remove if you can't scoot it forward to get to the bolt. Even with flexhead sockets, it took finding two 10mm bolts on the screw drive and some acrobatic, upside down finger spinning to remove them so I could slide the seat. Anyway, here's some details. When I looked underneath this is what greeted me. No obvious kinks/shorts/melted wires or other issues.

Pic 1: https://i.imgur.com/0DMOCLN.jpg

I disconnected everything seat related, loaded up a fresh 40a fuse and bingo. Windows worked, door locks worked. FINALLY! From there, I started plugging things in one by one until I found it was the big center connector. This one actually splits/distributes power to motors individual motors and also leads to the seat controls. Removing all the motors narrowed it down to the actual connector that leads to the seat controls themselves. Here's a bad pic of it but take note it doesn't go to that motor and instead wraps behind it and direct to the controls.

Pic 2: https://i.imgur.com/Q9qkgv7.jpg

I traced the cables all the way into the seat control mechanism but was unable to see anything obvious. No fried parts, no melted anything. However, when I connect it I can hear a distinct spark from inside the unit so it may be toast. Since I'm the only one who drives it, I don't need to move the seats so I decided to just disconnect the motor/control plug and put the airbag sensor thing back in. This was the hardest part (taking 2 hours) because of how silly the Maxima bolt design is on the rear left bolt. I thought it was bad getting it off but putting it back on was nuts. I ended up cutting some plastic on the rear of the seat to get a flex-head in there and by pure, blind luck I got it to stick and hold.

Anyway...long story short, I wouldn't have got here without Maxima.org's help. I'm sure I would have paid through the teeth for an electrical shop to find it and instead I'm only out about $40 for the fuses and junkyard relay. I'll check around for some seat controls next week but I can't imagine those being more than $50 used. Under $100 is a total win in my book. I'll go ahead and update the first post for future searchers and once again, THANK YOU

TunerMaxima3000

iTrader: (4)

Nice work seedy! Great job man, great updates and follow up, very happy you were able to track it down!

DennisMik

iTrader: (2)

Definitely some great detective work. Now that you've found it, I think I remember some other threads with this problem. Sorry that I didn't remember it before this.

SeedyROM

Thanks bud, always appreciate your input!

No worries at all! Your help was greatly appreciated getting me to it.