Help altima barely runs after bad battery many codes

[gwoods]

My gut is It needs an engine computer. It's a friends 2001 nissan altima gle. Her daughter was driving it and it stopped. She took it to autozone and the battery and alternator tested as bad. Both have been replaced.

Now nothing electrical works from the power mirror, sunroof, windows, radio, locks e fans nothing. The car somehow starts and will run if you keep rpm at about 2000 but as soon as you take your foot off the gas it dies. When running it sounds normal no vac mum leaks.

Codes
P0446 evap emmisions vent control circuit
P1605 at diagnostic communication line
P1490 vacuum cut/bypass valve
P0505 idle air control system
P0500 vehicle speed sensor
P0141 o2 heater circuit
P0135 o2 heater circuit


Clearing them and they come back when you start the car.

Could it be a relay?

[lne937s]

I would take a look at the O2 sensor. When both the alternator and battery wear out at the same time, it could be because of a short somewhere causing excess draw on the system. That O2 sensor heater circuit could be the culprit.

[gwoods]

Interesting thank you, could it also make everything else stop working?

I removed all the fuses under the hood and under the dash and only the radio fuse was popped. I replaced it and the radio started working again. I tried swapping new fuses for other spots and nothing else came back to life.

Also failed to mention none do the gauges work, tach, speedo , fuel, temp. Check engine light does not come on but the car has 11 codes ( some multiple times)

[PapaSmurf2k3]

Did they hook the battery up backwards?

[gwoods]

Very possible!

None of the fuses were blown but the radio but now nothing works electrically and the car will start right up and run fine if you keep the rpms up.

You thinking engine computer?

[PapaSmurf2k3]

I kinda am...

Pretty much all bets are off if you hook a battery up backwards (or jump it backwards). There's no telling what it could have f*** up.

[gwoods]

I'm so boggled by it firing right up? I would expect a fried ecu would be a dead car

[float_6969]

My very first thought was that the battery got wired up backwards. Did you check all of the big fuses under the hood? It could also be a bad ground somewhere. I would get out the FSM for that car and look up all the grounds on the wiring diagram. Clean all of them and make sure there aren't any missing.

[gwoods]

Confirmed car was jump started with cables crossed by a construction worker

[sx moneypit]

Confirmed car was jump started with cables crossed by a construction worker

[PapaSmurf2k3]

Well there you go!
How you go about fixing that, I have no idea.

[gwoods]

Fortunately I have a 99 so I can swap fuses and relays until it runs. If it's not a fried relay or fuse the. I will swap the ecu

[PapaSmurf2k3]

Good luck man, let us know how you make out.
Through the years, a lot of people have asked me what exactly to do to fix that.
I always just sort of hit them with:

[gwoods]

I swapped every fuse and relay between the two cars zero change it will get a junkyard ecu next week. That should fix it

[float_6969]

Something in the back of my mind tells me there are some diodes somewhere associated with the radio or the gauges that blow when that happens. I could be wrong though.

[gwoods]

The radio was the only blown fuse and now the only electrical thing that works you may be correct about the instrument cluster