Where's the Logic in this (electical gremlin)
09-20-2004, 07:39 PM
#1
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Join Date: Sep 2004
Posts: 35
Where's the Logic in this (electical gremlin)
Of course, we all realize there must be some logic why our car works (or not) in certain ways. So here's a challenge...
A month ago my power door locks quit. Well, they work from the key fob, but they don't work from the switch on either the driver or passenger door. So I know the lock actuator works, just not the 'in car' controls.
Then I noticed the passenger window was not controllable from the driver's door. Yes, it works on the passenger door though so again the motor part works, just not the driver's side controls.
Then a week later my kids say "why don't our windows work?" Sure enough, the rear windows are now uncontrollable from both the rear doors and the driver's door. Hmm. They worked last week when the passenger door window quit working.
Wait - it continues.... then I notice my "seat memory" feature has quit working.
At first I figured the switch control panel on the driver's door may have been fried. Now I think it's a common computer that controls these.
And I wonder if my heated steering wheel is tied to this somehow too. It heats up, but then it cools off. It doesn't stay hot.
I've only had my 2002 SE (6 speed) for a couple months, so I don't know if the steering wheel heater has always worked this way. Wonder if others works this way.
If someone can see the logic in this I'd sure appreciate the guidance, rather than opening up my wallet to the stealer....
Many thanks from a newbie. And thanks to all those that originally told me (anonymously) that the 02 with six speed is the way to go. I do love the car in all the critical ways. It's the smoothest drive I've ever had.
Cheers,
Jerry
A month ago my power door locks quit. Well, they work from the key fob, but they don't work from the switch on either the driver or passenger door. So I know the lock actuator works, just not the 'in car' controls.
Then I noticed the passenger window was not controllable from the driver's door. Yes, it works on the passenger door though so again the motor part works, just not the driver's side controls.
Then a week later my kids say "why don't our windows work?" Sure enough, the rear windows are now uncontrollable from both the rear doors and the driver's door. Hmm. They worked last week when the passenger door window quit working.
Wait - it continues.... then I notice my "seat memory" feature has quit working.
At first I figured the switch control panel on the driver's door may have been fried. Now I think it's a common computer that controls these.
And I wonder if my heated steering wheel is tied to this somehow too. It heats up, but then it cools off. It doesn't stay hot.
I've only had my 2002 SE (6 speed) for a couple months, so I don't know if the steering wheel heater has always worked this way. Wonder if others works this way.
If someone can see the logic in this I'd sure appreciate the guidance, rather than opening up my wallet to the stealer....
Many thanks from a newbie. And thanks to all those that originally told me (anonymously) that the 02 with six speed is the way to go. I do love the car in all the critical ways. It's the smoothest drive I've ever had.
Cheers,
Jerry
09-21-2004, 08:31 PM
#4
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Posts: 35
Thanks for writing.
No, the car has no aftermarket alarm, or any other electrical mods of any type.
I guess I am suspecting either the computer or a ground problem. But why those rear door windows would quit working, even from their door switches baffles me. It's a great challenge, but I need someone who understands the wiring to find the logic in it all. There's lots of data, just not much knowledge being applied.
Thanks,
Jerry
No, the car has no aftermarket alarm, or any other electrical mods of any type.
I guess I am suspecting either the computer or a ground problem. But why those rear door windows would quit working, even from their door switches baffles me. It's a great challenge, but I need someone who understands the wiring to find the logic in it all. There's lots of data, just not much knowledge being applied.
Thanks,
Jerry
09-23-2004, 11:36 AM
#6
Old Fuddy Duddy
Join Date: Feb 2001
Posts: 2,712
You are correct
In your assumptiont that there is a common computer that takes care of the "creature" comforts in your car. I am unfamiliar working with it, or diagnosing it either.
The person you might want to contact is IceY2K1. He has been instrumental in helping people read the schemo's for electrical. He has a 2k1, but he might be able to give you some ideas on what to look for.
Other than that, I can be of no service.
Good luck man, electrical gremlins are a pain to hunt down.
The person you might want to contact is IceY2K1. He has been instrumental in helping people read the schemo's for electrical. He has a 2k1, but he might be able to give you some ideas on what to look for.
Other than that, I can be of no service.
Good luck man, electrical gremlins are a pain to hunt down.
09-23-2004, 08:11 PM
#7
Supporting Maxima.org Member
Join Date: Oct 2002
Posts: 109
I think one thing all your symptoms share in common is that they involve wiring that passes through the driver's door. (All the passenger windows are interlocked by a switch on the driver's door, for example.)
There is a huge multiple connector behind the lower left kick panel where the harness for the LF door is joined to the body harness. Wonder if it's loose or got some corrosion in it? I've never had it apart on my car and it looks hard to reach.
This is grasping at straws... but an intermittent wiring problem seems more likely than an intermittent computer problem. (The Nissan term for the computer is "smart entrance control unit.) And I remember another car I had with a very similar problem: one of the rear door windows worked only when it felt like it, usually refusing to go up during rain. (How do they know these things.) The problem eventually proved to be a connector inside the door that had not been fully pushed together, so that the water seal leaked and eventually caused corrosion of some of the pins. Also, although the smart entrance control unit does control many things on the car, according to the FSM the seats have their own controller and the wiring diagram does not show any connection to the s.e.c.u.
As for the steering wheel, that's normal. The switch on the lower dash energizes a timed relay (timed by, guess what, the "smart entrance control unit") which stays on for 30 minutes or until you push the switch a second time or turn off the ignition. However there is also a thermostat in the steering wheel that must be closed for the heater to operate. I don't know whether the thermostat has a huge switching differential, or whether there is poor thermal contact between the steering wheel rim and the thermostat, but the observation is that the wheel gets very hot, then the heat goes off and the wheel has to cool down almost completely before the thermostat closes again. If you look through the forum postings you will see that a lot of other people have mentioned this. I guess the Nissan philosophy is, you should be so grateful to have a feature like that on a car that does not cost $60k that you shouldn't expect it to work sublimely well too!
There is a huge multiple connector behind the lower left kick panel where the harness for the LF door is joined to the body harness. Wonder if it's loose or got some corrosion in it? I've never had it apart on my car and it looks hard to reach.
This is grasping at straws... but an intermittent wiring problem seems more likely than an intermittent computer problem. (The Nissan term for the computer is "smart entrance control unit.) And I remember another car I had with a very similar problem: one of the rear door windows worked only when it felt like it, usually refusing to go up during rain. (How do they know these things.) The problem eventually proved to be a connector inside the door that had not been fully pushed together, so that the water seal leaked and eventually caused corrosion of some of the pins. Also, although the smart entrance control unit does control many things on the car, according to the FSM the seats have their own controller and the wiring diagram does not show any connection to the s.e.c.u.
As for the steering wheel, that's normal. The switch on the lower dash energizes a timed relay (timed by, guess what, the "smart entrance control unit") which stays on for 30 minutes or until you push the switch a second time or turn off the ignition. However there is also a thermostat in the steering wheel that must be closed for the heater to operate. I don't know whether the thermostat has a huge switching differential, or whether there is poor thermal contact between the steering wheel rim and the thermostat, but the observation is that the wheel gets very hot, then the heat goes off and the wheel has to cool down almost completely before the thermostat closes again. If you look through the forum postings you will see that a lot of other people have mentioned this. I guess the Nissan philosophy is, you should be so grateful to have a feature like that on a car that does not cost $60k that you shouldn't expect it to work sublimely well too!
09-24-2004, 01:17 PM
#8
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Join Date: Sep 2004
Posts: 35
Thanks so much, imjd.
I'll see about that left floor kick panel this weekend. I think trying to pull it apart and reseat it is well worth while.
You mention an interesting point... the seat memory function is not part of S.E.C.U? If not, then it further leads to the conclusion that it's wiring, not computer. That might be key.
And to add to this all, well my sunroof wouldn't open last night. I remember someone writing about some "reset" sequence to run thru. If you know what it is, or a url where it was discussed, it'd be most appreciated. Or maybe the wiring leads back down thru the driver door. :-)
Thanks,
Jerry
I'll see about that left floor kick panel this weekend. I think trying to pull it apart and reseat it is well worth while.
You mention an interesting point... the seat memory function is not part of S.E.C.U? If not, then it further leads to the conclusion that it's wiring, not computer. That might be key.
And to add to this all, well my sunroof wouldn't open last night. I remember someone writing about some "reset" sequence to run thru. If you know what it is, or a url where it was discussed, it'd be most appreciated. Or maybe the wiring leads back down thru the driver door. :-)
Thanks,
Jerry
09-24-2004, 03:43 PM
#10
I'm not completely following your steering wheel heater problem. Are you saying that it only heats once or that it cycles on and off? It appears that many of us have the kind where the heat cycles on and off.
The driver door connector sounds like a good candidate. The only hesitancy I would have in this theory is that if the connector was really bad then the keyfob would presumably not work either. This sounds like the best thing to review though.
Another thing to check is if your key in the door lock work the locks and windows? Holding the key lock in the locked position, the windows should close (and vice versa). Hope this helps.
The driver door connector sounds like a good candidate. The only hesitancy I would have in this theory is that if the connector was really bad then the keyfob would presumably not work either. This sounds like the best thing to review though.
Another thing to check is if your key in the door lock work the locks and windows? Holding the key lock in the locked position, the windows should close (and vice versa). Hope this helps.
09-24-2004, 05:09 PM
#11
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Join Date: Dec 2001
Location: Charlotte, NC
Posts: 1,687
First off, check all the fuses in the fuse box in the main cabin. If any are blown, replace them. If they all check out ok, keep reading.
At this point, my vote is for the connector in the kick panel. I've seen instances happen where the sunroof, map lights, homelink, and other overhead features stop working... and every time it is the connector. In your case, all the wires for the windows and locks on the driver's door are run through one connector in the driver's kick panel.
To test this theory, do as mentioned above. Try your key in the lock. Turn and hold it in the unlock position. If the windows don't roll down... it's most likely that connector. If they do, read on.
The key and window modules are controlled by the SECU (Smart Entrance Control Unit), which is located in the dash to the right of the steering wheel (and to the left of the radio). The SECU utilizes a single wire that is bi-directional. The SECU talks to a mini-computer which is located inside the driver's front door. The passenger's front door also has a mini-computer as well.
If the power lock switch works on the passenger's side, but not on the driver's side, it is probably the driver's side mini-computer that has failed. When the driver's side mini-computer fails, the following items will stop working or work intermittently:
1) All windows (regardless of which switch you use)
2) Driver's door lock switch
3) Electric window up/down using the key
4) Memory seats
If the passenger's side is working and the driver's side is not and you've already confirmed that it is not the door harness connector (in the kick panel), it is the mini-computer in the driver's side.
If neither the passenger's side nor the driver's side is not working, it is probably the SECU under the dash.
In either case, you should take the car to the dealer if you are still under warranty. If not, write back with the results from the above steps. And don't order any parts just yet.
At this point, my vote is for the connector in the kick panel. I've seen instances happen where the sunroof, map lights, homelink, and other overhead features stop working... and every time it is the connector. In your case, all the wires for the windows and locks on the driver's door are run through one connector in the driver's kick panel.
To test this theory, do as mentioned above. Try your key in the lock. Turn and hold it in the unlock position. If the windows don't roll down... it's most likely that connector. If they do, read on.
The key and window modules are controlled by the SECU (Smart Entrance Control Unit), which is located in the dash to the right of the steering wheel (and to the left of the radio). The SECU utilizes a single wire that is bi-directional. The SECU talks to a mini-computer which is located inside the driver's front door. The passenger's front door also has a mini-computer as well.
If the power lock switch works on the passenger's side, but not on the driver's side, it is probably the driver's side mini-computer that has failed. When the driver's side mini-computer fails, the following items will stop working or work intermittently:
1) All windows (regardless of which switch you use)
2) Driver's door lock switch
3) Electric window up/down using the key
4) Memory seats
If the passenger's side is working and the driver's side is not and you've already confirmed that it is not the door harness connector (in the kick panel), it is the mini-computer in the driver's side.
If neither the passenger's side nor the driver's side is not working, it is probably the SECU under the dash.
In either case, you should take the car to the dealer if you are still under warranty. If not, write back with the results from the above steps. And don't order any parts just yet.
09-24-2004, 08:50 PM
#13
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Join Date: Sep 2004
Posts: 35
Originally Posted by ajahearn
I'm not completely following your steering wheel heater problem. Are you saying that it only heats once or that it cycles on and off? It appears that many of us have the kind where the heat cycles on and off.
.
.
But a few other folks mention that they can turn their switch off and then on again to get it hot again. I haven't found this to be the case with my steering wheel. If I turn it off, then on, it stays the temp it is. No more heat.
But I am so appreciative of the thoughts. If you think this set of circumstances leads you to a conclusion I'd love to hear it. I hope to post again tomorrow with the results of the excellent problem solving you guys have helped me with.
Thanks,
Jerry
09-24-2004, 09:21 PM
#14
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Hi Studman, et al.
I couldn't wait, so I popped outside. Now, I haven't done step one yet. That is I won't have enough light to really check all the fuses until tomorrow, but I wanted to follow the concept of the key in the lock.
So I went outside and put my key in the driver's door. Upon figuring out which way to turn to lock and unlock, and holding the key unlocked, I determined that the driver's side lowered just fine. NOTE, only the driver's side lowered. If they're both supposed to lower, well that's not good. Then I walked around to the passenger side and went to try the same test. Funny thing. There's no key hole on the passenger side. :-) Funny how you never notice stuff like that with the remote key fob. <still laughing at self for trying>
So I pushed and held the unlock button on the key fob, and low and behold the windows DO NOT lower anymore. Hmm. They did a month ago when I tried it last.What does it all mean...
So as for the passenger side controls on the passenger door. The window button works, but the door lock button does nothing. That is parallel in function to the driver's side door. The driver's side control buttons only works the driver's window. The rest don't work. Not the remaining three window buttons nor the lock button.
I also paid extra attention to the seat memory buttons. The buttons appear to work thru the setting procedure properly. That is, when you push set, the buttons light for five seconds showing they have a seat position memorized. If you move the seat and try to set the position, they do as they're supposed to. The button lights for about five seconds saying "I'm set". But they do not move the seat to the memorized positions at all. If I move the seat all the way up, and then push a memory button down solid for a couple seconds, nothing happens. They don't move. AND I do have the parking brake engaged.
On the bright side, the resetting of the sunroof worked great. Thanks, PoLo.!
Great problem solving here. Given Studman's problem isolation logic, I think I am heading to a SECU... but what say you?
Thanks,
Jerry
I couldn't wait, so I popped outside. Now, I haven't done step one yet. That is I won't have enough light to really check all the fuses until tomorrow, but I wanted to follow the concept of the key in the lock.
So I went outside and put my key in the driver's door. Upon figuring out which way to turn to lock and unlock, and holding the key unlocked, I determined that the driver's side lowered just fine. NOTE, only the driver's side lowered. If they're both supposed to lower, well that's not good. Then I walked around to the passenger side and went to try the same test. Funny thing. There's no key hole on the passenger side. :-) Funny how you never notice stuff like that with the remote key fob. <still laughing at self for trying>
So I pushed and held the unlock button on the key fob, and low and behold the windows DO NOT lower anymore. Hmm. They did a month ago when I tried it last.What does it all mean...
So as for the passenger side controls on the passenger door. The window button works, but the door lock button does nothing. That is parallel in function to the driver's side door. The driver's side control buttons only works the driver's window. The rest don't work. Not the remaining three window buttons nor the lock button.
I also paid extra attention to the seat memory buttons. The buttons appear to work thru the setting procedure properly. That is, when you push set, the buttons light for five seconds showing they have a seat position memorized. If you move the seat and try to set the position, they do as they're supposed to. The button lights for about five seconds saying "I'm set". But they do not move the seat to the memorized positions at all. If I move the seat all the way up, and then push a memory button down solid for a couple seconds, nothing happens. They don't move. AND I do have the parking brake engaged.
On the bright side, the resetting of the sunroof worked great. Thanks, PoLo.!
Great problem solving here. Given Studman's problem isolation logic, I think I am heading to a SECU... but what say you?
Thanks,
Jerry
09-24-2004, 09:39 PM
#15
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Join Date: Dec 2001
Location: Charlotte, NC
Posts: 1,687
I would definitely say that the SECU has gone bad. After reading the symptoms above, the windows should have rolled down when you used the key fob. Since they didn't, that leads me to the SECU.
Since the driver's window DID roll down when you used the key, but not the passenger's side, that also tells me that it is the SECU. The signals from the mini-computer in the driver's door should have been sent out to the SECU, which should have relayed it to the passenger's door.
If you are still under warranty, take the car in. If not, see if you can find another Maxima owner who is local and swap the driver's side window switches. If the problem still persists, order a SECU. Once the SECU is in, you may have to have a dealer install and program it. I haven't replaced one before, so I'm not sure if it stores a copy of the NVIS information or not. I know the ECU and the NVIS module does, but I am not sure if the SECU does.
Definitely let us know what the results are when you find out.
Since the driver's window DID roll down when you used the key, but not the passenger's side, that also tells me that it is the SECU. The signals from the mini-computer in the driver's door should have been sent out to the SECU, which should have relayed it to the passenger's door.
If you are still under warranty, take the car in. If not, see if you can find another Maxima owner who is local and swap the driver's side window switches. If the problem still persists, order a SECU. Once the SECU is in, you may have to have a dealer install and program it. I haven't replaced one before, so I'm not sure if it stores a copy of the NVIS information or not. I know the ECU and the NVIS module does, but I am not sure if the SECU does.
Definitely let us know what the results are when you find out.
09-26-2004, 08:32 AM
#16
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Posts: 35
Thanks very much, Studman. I tend to agree the SECU appears guilty. I can't see it being the switches in the door.
I wish there was a way to pull the secu and test it, or to reset it. I work on PC's a lot, and sure they screw up, but you can generally fix them. It's usually software.
With that in mind, I tried pulling the battery ground the other night wondering if it might cause the computers to 're-boot". No luck. I wonder if the SECU has a capacitor or battery to help it retain power, and didn't reboot.
Oh well, I have no idea what a SECU will cost, but I bet they don't give them away. No, not under warranty anymore. I have about 65K on my car.
I wish there was a way to pull the secu and test it, or to reset it. I work on PC's a lot, and sure they screw up, but you can generally fix them. It's usually software.
With that in mind, I tried pulling the battery ground the other night wondering if it might cause the computers to 're-boot". No luck. I wonder if the SECU has a capacitor or battery to help it retain power, and didn't reboot.
Oh well, I have no idea what a SECU will cost, but I bet they don't give them away. No, not under warranty anymore. I have about 65K on my car.
04-26-2005, 01:35 PM
#17
Seoul Man
Join Date: Jun 2004
Posts: 1,010
Sorry to revive a dead thread, but it's better than starting another one like all the other noobs, right?
I'm not having nearly as many problems as Jeraldo, but my Maxima seems to have intermittent electrical problems too. Every few weeks, my sunroof decides not to open with the slider switch. The switch that tilts the glass up and down ALWAYS works, but the slider switch that actually makes the glass slide back and forth does absolutely nothing. Normally, I just try to ignore the problem, then a few hours or a few days or a week later, the sunroof magically works again. My sunroof, which worked last week, is going through one of its malfunctioning phases today. I've never tried the reset procedure (holding the "close moonroof" button for five seconds), but I will do that today to see if it helps. I remember reading a bulletin that mentioned the sunroof problem after the battery has been disconnected. I recently disconnected my battery to reach the back of the driver's side headlight, so that could have triggered this most recent sunroof malfunction. Like I said before, the problem is intermittent. I can't remember if it was associated with a disconnected battery EVERY time it has happened, but I can't rule out that possibility either, since I've been doing a lot of work in the past few months that required me to disconnect the battery.
My question is this:
If the bulletin associates the problem with a disconnected battery and recommends the reset procedure to fix the sunroof, how come the problem occasionally fixes itself? I am a Nissan fan, and I will always be one, but sometimes I wonder if that means I'm a masochist. I know every car has its problems, but somehow I had less of these totally f*cking weird problems with my Toyota.
I'm not having nearly as many problems as Jeraldo, but my Maxima seems to have intermittent electrical problems too. Every few weeks, my sunroof decides not to open with the slider switch. The switch that tilts the glass up and down ALWAYS works, but the slider switch that actually makes the glass slide back and forth does absolutely nothing. Normally, I just try to ignore the problem, then a few hours or a few days or a week later, the sunroof magically works again. My sunroof, which worked last week, is going through one of its malfunctioning phases today. I've never tried the reset procedure (holding the "close moonroof" button for five seconds), but I will do that today to see if it helps. I remember reading a bulletin that mentioned the sunroof problem after the battery has been disconnected. I recently disconnected my battery to reach the back of the driver's side headlight, so that could have triggered this most recent sunroof malfunction. Like I said before, the problem is intermittent. I can't remember if it was associated with a disconnected battery EVERY time it has happened, but I can't rule out that possibility either, since I've been doing a lot of work in the past few months that required me to disconnect the battery.
My question is this:
If the bulletin associates the problem with a disconnected battery and recommends the reset procedure to fix the sunroof, how come the problem occasionally fixes itself? I am a Nissan fan, and I will always be one, but sometimes I wonder if that means I'm a masochist. I know every car has its problems, but somehow I had less of these totally f*cking weird problems with my Toyota.
08-06-2007, 08:39 PM
#18
I apologize for resurrecting an old thread, but I had no luck after searching and I can't create my own post yet. This was the closest post I could find to my issue.
I have a 2k SE and the sunroof decided to quit working right tonight. If someone can point me to the reset procedure, I'll end things there. If needed, I can describe the exact issue.
I have a 2k SE and the sunroof decided to quit working right tonight. If someone can point me to the reset procedure, I'll end things there. If needed, I can describe the exact issue.
08-06-2007, 08:53 PM
#19
Originally Posted by PadawanKnight
I apologize for resurrecting an old thread, but I had no luck after searching and I can't create my own post yet. This was the closest post I could find to my issue.
I have a 2k SE and the sunroof decided to quit working right tonight. If someone can point me to the reset procedure, I'll end things there. If needed, I can describe the exact issue.
I have a 2k SE and the sunroof decided to quit working right tonight. If someone can point me to the reset procedure, I'll end things there. If needed, I can describe the exact issue.
fyi, there's a newbie thread.
08-07-2007, 06:23 AM
#20
Originally Posted by CoolMax
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