i have a 15amp fuse in the box next to the battery that keeps blowing, and is required for the car to keep running. it is the the 'Engine Control 1' fuse as labeled on the fuse cover. the story.

so im preparing to supercharge my max and in some weekend at the end of april/beginning of may (dont quite remember) i put in the new thermostat housing. there is a bracket on the alternator that gets removed, and that has a ground wire for the alternator on it. i was just in a hurry and never got around to putting the ground back on the alternator cause i didnt have the proper attachment and i had to go to a party.

tues. may 22nd - went to a drag strip and met some other local .org people there. my first time at a strip, and after it was over i was driving home and the car just seemed to stall. it wouldnt rev anymore, and it ended up being a blown fuse in the box by the battery. unfortunately i do not remember if it was the one label 'Eng Cont 1' or the one that says 'Eng Cont 2'.

sat. june 2nd - i install an apexi safc2 and a zeitronix unit. no problems, car runs fine. i made sure to do the thing where the ground wires have to be 1mm apart and put them in line properly.

sun. june 10th - Engine Control Fuse 1 blows. i replace it and it starts up and drives fine.

today - Engine Control Fuse 1 blows again, and every other time i put in a fuse. I finally reattached my alternator ground wire, and the fuse still blew.


so the fuse blew before i put in the apexi and zeitronix. i seriously spent my time and tripled checked to make sure it was all hooked up right. so i can be fairly positive those are not causing me the problem.

i did unhook my battery and then put in another fuse and that didnt work.
it sounds like it wants to start and you can smell gas so everything is shooting off except the spark plugs.

anyone ever come across this??

 

Well it can be a lot of things:
Alternator shorted, maybe the wires to the fuse box are bad/crossed,
Rectifier-regulator burned out, leads pinched causing shorting, shorted/bad coil or a shorted wire going to the coil.
Sometimes fuel pump could be causing the short and blowing engine controle fuse.
Any mods recently put on?

 

how about you re-read my post. june 2nd i put on mods, but the fuse blew BEFORE i put them on.

 

If the alt wasn't grounded it's possible you fried it. Try getting it tested somewhere to see if it's still good.

 

so i did some troubleshooting today after google searching and coming across a mention of how the alternator could output to much power to the system
http://forums.evolutionm.net/archive.../t-203548.html

i took out the alternator, took me just over an hour to get it out. had to take off the y-pipe, engine fans, and move the ac compressor around all as mentioned on motorvate.ca
http://www.motorvate.ca/mvp.php/500

i also re-checked all my wiring i had done to install the safc2 and the zeitronix. all of those wires are fine, not touching anything causing a short, and as i have mentioned before the fuse blew BEFORE i ever installed these two items.

the troubleshooting:
-with alternator in and plugged in, the fuse blows when i try to turn the car on.

-with alternator out/unplugged and the ecm wiring harness unplugged, the fuse does not blow when i turn on the car. so i think this rules out a possible ignition switch problem since those two items are unplugged and the fuse is fine (ignition area is the only other area with wiring done to it cause extra gauges are attached and have been attached for almost 2yrs).

-with alternator out/unplugged and the ecm wiring harness plugged in, the fuse does not blow when i try to turn the car on. the car started, and the fuse did not blow. so i think this rules out a possible wiring harness problem from hooking up the safc2 and zeitronix.

so it seems that it could possibly be the alternator sending to much power through the electrical system. however odd that may be. i have never heard of this problem before.

i went to get the alternator tested at NAPA, but they dont have the right adapter to test it, typical. i didnt try anywhere else cause i had to bring back the car i was borrowing.

can anyone think of other troubleshooting stuff?

 

When a A33 starts blowing a fuse labeled 'Engine Control' it is most often attributed to a bad or shorted heater circuit in a secondary O2 sensor.

 

im a fed spec, so my primary o2's are the ones on my y-pipe (right?), and my only secondary one is attached after the cat.

i have had my cat off for over 3 years now and have the secondary o2 sensor tied up to a head shield next to the exhaust. i will take a look at it again, but im pretty sure when i looked at it today the wires and everything were fine and not damaged at all.

 

so i checked those wires, and they are not damaged, still completely wrapped with the stock insulation stuff.

i have not heard of a failing secondary o2 sensor causing a fuse to blow before. there have been quite a few people who have posted on here over the years about bad secondary o2 sensors and i do not recall them ever having a fuse blow.

i am not trying to prove you wrong, but just wondering where you got this info from.

 

he got it from working on my car. after my headers went on on my old 2k1, we ended up leaving the o2 sensors unplugged. the cel was obviously on but the fuse was popped as well. i replaced the fuse and it would pop within a minute of the car turning on. we ended up using a sim to replace the 2 secondaries on my cali spec and i replaced the fuse afterwards. it never popped again. EDIT- we did plug up the secondaries after the headers but the heater went bad and thats when it started popping.

 

Just chalk it up to a few counts of personal experience is all. And I can't say for certain that this is your problem without further info, but it still could be. Just to be safe and rule out the secondary O2 sensor, try unplugging it for awhile.

 

i had a feeling it was from experience. ill give unplugging it a shot. thanks.\

 

well i just got done hooking everything back up, and when i tried to start the car the fuse did not blow, so i think i have ruled out the alternator being the culprit.

i did get under there and unplug the secondary o2 sensor. for all you Fed Spec guys its quite easy to do if you ever need to do so. just remove the rubber grommet under the car and pull the wires until you can unplug the o2 sensor.

i also was reading up in the FSM for the 5.0 gen. unfortunately it isnt a Fed Spec FSM, but good enough. basically it was saying that after the car has gone through the 2 minute or so start up cycle, all of the o2 sensor heaters will kick on once the car has reached 43mph or 3,600rpm or higher(i think this is what is was saying at least).
anyway, that would correlate with when the fuse blew on me on the may 22nd, june 10th, and june 12. it was just after i had started driving the car and it had been running for just over the initial start up cycle.

im gonna take it for a test drive and see if the problem is solved, or if it is another o2 sensor, or if im really screwed.

 

How do you know this?

 

Hmm.. and i wonder where you could find one?

 

well you cant say i didnt do my homework.

http://forums.maxima.org/showthread....935#post275935





pages EC-415 through pages EC-446 reference what speeds the o2 sensors are kicking on at and such as i said in post 12.



so i went to test it with the rear o2 unplugged, and the fuse blew after i let it warm up and it moved about 5 feet. replaced the fuse, unplugged the front bank o2 sensor, started it up and it did not blow. i just had a check engine light after awhile cause i had an o2 sensor unplugged. i even drove up to above 43mph and 3,600rpm and still the fuse didnt blow. so maybe, possibly i found the problem.

 

What's an 02? A year? O2 > 02. You still haven't answered my question though.

 

sorry bout that, oxygen sensor.

you asked how i knew it wasnt a Fed Spec FSM, and i posted pics from the FSM i have, which appears to be a Cali Spec FSM.

 

Check the sig.


Also, if it's your primary causing the problem you need to get that replaced quickly. The ECU will run very very rich if it can't get AFR feedback from that sensor.

 

Nice pictures! I am doing an 02 sim install on mine soon, and these will help out!

Thanks!

 

well hopefully this saga of troubleshooting is finally over. i just installed a new Bosch o2 sensor that i got from NAPA, $116.91

Autozone wanted $178 before tax!

and here is a pic of the fuse

 

just fyi for next time, if you can wait a day or two then check out oxygensensors.com best prices i have found on bosch or walker ones. they also have an org discount of around 10% and no i dont work or know anyone that works for them.

 

Sorry to bring up an old thread, but this was exactly the problem for me. O2 sensor wire shorting on the engine block and blowing the engine control fuse. Only from finding this thread was I able to find the problem after 2 days of troubleshooting

 

Read through this thread here…

seems this is for a 5th gen..?
I’ve got a ‘99 4th gen maxima automatic trans… recently the coolant hose behind UIM by egr tube, coolant leak.
had to take the whole UIM off to get a new hose secured on… after a couple days, park and neutral idled around 1500rpm… read some threads here for 4th gens that the MAF and air filter need cleaned… ppl also suggested doing things on the iacv and throttle cables….
cleaned MAF, IACV and short ram air filter…

car drove for a single day at a low idle 400-500rpm and sputter in acceleration..

the next day, car cranked, turned over and died…

The engine control 2 fuse blew..

Could the coolant leak have landed on O2 sensor causing the eng cont 2 fuse to blow??