Autozone pulled these 3 codes simultaneously, help needed - thanks.
1996 SE Maxima.

P0325 is relatively normal, the KS code can be set off by the O2 sensor code, or it just needs to be replaced if it never has been before.

So, you didn't do anything about the codes yet? P0135 is for your bank 1 O2 sensor, probably just died. Test it, if it fails then replace it.

P0600 is a bit more involved, really.

So what do you do about a P0600 (A/T control unit communications failure)? From the FSM it appears that if it's not a loose or corroded connection between the TCM and the ECM, which seems unlikely, then you have to replace the TCM. I've had this code for a couple of years - other than some occasional wacky shifting (which may not even be related) I don't notice anything wrong.

Is there any reason to do anything about P0600? A new TCM is $550.

i can get u a used tcm for $80

Never had to diagnose or solve the code myself, but I'd check the connections as the FSM specified (which is a PITA if you're thorough, opening up the engine control harness), then replace the TCM.

What year are you? I've got a 95/96 TCM for $45 shipped

If your state does emissions, then you'll fail with a CEL (depending on vehicle year and state). It might also fix the shifting issue if the TCM is bad, but

1997. I'm not ready to swap the TCM out yet - P0600 has never lit the CEL, I didn't know it would. Every so often, the O/D light blinks on starting the car, so I hook up the scanner to find P0600 with no CEL, and then I erase it. Maybe if I leave it long enough it'll light the CEL? A couple of times when I hooked up the scanner after doing some work, just to see if I screwed anything up and had pending codes, I find a P0600 and erase it. I just assumed it was always there.

I've never pulled the harness connector off the ECM, and I've never laid eyes on the TCM. I didn't think it would be a big deal to backprobe the connections between the TCM and the ECM - are you saying it is?

To OP - sorry for derailing your thread, but P0600 was one of your codes so hopefully you'll be somewhat interested.

It's not too big a deal to test continuity, but getting a hold of the harness to move it around and make sure there are no breaks is a bit of a pain.

I replaced the sensor, all the wiring looks, good, why the devil am I still getting 0135 after erasing the codes with my scan tool?

Did you replace the proper sensor?

Bank 1 is firewall side of engine, bank 2 is radiator side

Yes, both sensors read bad, just replaced one, other when I get room on my plastic or a crowbar in my boss's wallet

I just replaced the camshaft position sensor the oxygen sensor was three weeks ago, could the bad cam sensor screw up an oxy?

why did you replace the camshaft sensor when you got a code for O2 sensor?


Which sensor did you replace on the O2s...? Be specific. firewall side or radiator side?

Had camshaft sensor code too, rad side. Trying to clean them both in gasoline overnight

Radiator side o2 sensor is bank 2...the code you said you have is bank 1. There's your problem

Both sensors are coding.