Need help diagnosing a couple electrical problems...

[Maverick7687]

I have a had a couple electrical problems with my 1998 Maxima. I have put up with them so far but they are now just getting to the point where it is tearing at me because I know something is wrong and I don't have the full functionality of the car.

They could possibly be related but I don't see how.

1) The horn. When hooked up, the horn works normally, until it decides to stick that is. It will just hang like you are holding it down and no amount of beating on the steering wheel will help. The only way to stop it is to just get out and unplug the horn.

This also happens when the horn is hooked up and the 'Panic' button is pressed on the remote.

2) The alarm. It does not work whatsoever. You can get out of the car, press the lock button on the remote and the doors will lock and 'Security' light will remain on for 30 sec. After which you can reach inside and unlock any door and start the car. No lights flashing, no horn, nothing.

3) Fog lights. When I first bought the car last year about this time, they worked fine. When it started warming up they blew a fuse. I replaced it after about a week of it being blown and they worked for about three days after. I replaced the fuse again and now only the passenger side works but the fuse does not pop anymore. What gives?

I really don't know where to start other than check wiring, or what to replace. If anyone can shed some light on this it would be great. I have posted up about the alarm problem before IIRC but got nowhere. Maybe this time will be better.

Thanks, -Tim

[MinisterofDOOM]

The horn could be related to the alarm issue, or could be isolated. I'd start by checking the horn relay. That sounds like the most likely cause to me. If you have a known good relay of the same type, swap them out and see what happens.

As for the alarm system:Again, I'd start by checking related fuses and relays. It seems to me if the system appears to arm properly (the SECURITY light comes on), it is probably related to the lock sensors themselves. Also, check and see if unlocking the doors from inside with the power lock buttons instead of the physical lock slider makes any difference.

Fog lights:Check your grounds. Check fog light wiring on the driver side. Now that it's winter, the roads are wet and snowy again. Considering the fact that they've gone twice at about the same time of year, I'd suspect a wiring issue that's worsened by all the wetness.

[Maverick7687]

Forgot about one small, possibly important detail. The hood sensor for the alarm broke off so it is not hooked up. I know that won't fix the horn issue but would it make the alarm not completely arm?

[MinisterofDOOM]

Yeah, it probably would. It should have the same effect as leaving a door open. You should be able to bypass the switch and just short the wires together (or apart, whichever the closed hood position is) to solve that problem if you don't want to have to buy a replacement. I find the hood sensor more irritating than helpful anyway. I've had it go off on me while working under the hood. NOT a fun surprise.

[alexlloyd]

In the Factory Service Manual page EL154 shows how to test these items with the interior light showing fault codes

[Maverick7687]

In the Factory Service Manual page EL154 shows how to test these items with the interior light showing fault codes

EL154 in mine shows self-diagnostics of the Cruise Control system. I found what you are talking about on EL175 though. That's pretty neat, I'll have to try it.