Hey all. I'm stumped here and hoping someone can help. Im having issues with starting my 2002 6spd max. I aapologize advance for the long message, but I feel the full story is needed. Heres the full story:

I went on a week and a half long vacation about 3 weeks ago. I didn't have time to fill her up with gas before I left and she was very very close to E. When I returned back to NY it was late and I had to work the next morning, so I got my stuff out the trunk and while there I started her....she fired up with no problem at all. Let it run for about a minute and left. Next day after work I go back to my car and she won't start. She cranks and cranks, but nothing more. I thought maybe I pushed it to the limit and she was completely dry in gas, so I got my portable gas can and put 2 gallons in. Go to start and still nothing.

At that point I noticed the security light in the clock was steadily on when I turned the key to the run position. After research I came to the conclusion that the NATS system had locked me out and would need my keys reprogrammed. Fine, found someone who has the equipment to do it and when he came we found another issue. The obd plug isn't communicating with the computer. He tried a few times and at this point I noticed the Service Engine Soon light isn't even illuminating at all when key is turned to the run position. He also has a 5th gen, so he took my computer out, put it in his car and it still wasn't communicating. Reconnected his ecu and it connected right away.

I bought a replacement ecu and it arrived yesterday. Installed it turn the key to run and still no Service Engine Soon light . I dont have a scanner yet, it's on the way, so I couldn't test if it was able to communicate, but I was expecting to see the SES light come on. I checked every fuse under the hood by the battery, all the fuses that under the instrument panel and even switched the ecu fuse by the battery with another identical one..all the fuses are good, still no change.

What am I missing...what else could my issue be? Any help would be greatly appreciated. Want to get my baby girl running again

 

Your car will not start with the new ECU - not before you program it to learn the identity of your car keys.

 

Buy a vag com cable from ebay and download NDS2 on a laptop to program your new key(s)

Make sure you have all the keys including spare keys to program at the same time because in not they won't work after you erase and reset the new key

 

oh ok. I kinda figured that, but I thought at least the check engine light would've illuminated when I put new ecu on.

 

ok. I downloaded NDS2, now just looking for vag com cable. All the ones I see on Amazon say they're for Audi and VW. Is there a specific one for Nissan? Tried searching for a Nissan specific one but nothing came up

 

Nope those are it, you can also download vcsd lite if you work on those pos audi/vw piles

 

Couple of simple things to check. The SES light - did you check that the light bulb isn't burned out?

Check fuses # 10 & 12. These fuses feed the OBD connector and the things you plug in look for 12 volts on certain pins (pins 8 & 16). Fuse 10 is top row, 2nd from the right - label is "IGN ELECTRONIC PARTS". Fuse 12 is center row, 1st on on left - label is "BAT ELECTRONICS PARTS".

 

you know I didn't check to see if bulb is blown or not....just figured its something else since it was working one day and not working the next. I think I did check all the fuses, but I will go back and check those two again tomorrow when I'm by my car.

 

i had that issue when I ordered my VAG
just make sure its ISO 9141 protocol
but if you cant connect you may need to check continuity from the data link plug to the ECm.

 

Not really, those cables are hit and miss no matter what. They're made in China ffs

 

Update: still no change. I'm still not getting any communication either, even with the replacement ECU. I know the obd2 port is getting power cause as soon as I plug in the reader it powers right up, but it doesn't communicate with the ecu. I dont know what to do.....any other ideas???

I've seen some posts saying could be fuel pump or relay, but would that cause communication issues?? I swapped the ecm relay with another one that I know is working and nothing. Anyone able to suggest anything else? I'm stumped

 

I suspect it's a power supply issue relating to lines connected to the ECM relay. See the sub-section of the EC section in the FSM titled "Trouble Diagnoses for Power Supply," pages 156 to 162 or thereabout.

 

If there is some type of electrical interference it can prevent communication because the ecu can't figure out what it is being told. I'm saying that something else could have a short that is kicking back on the ecu. I had this happen when a dash cluster went out. No matter what we did it didn't communicate. Removed the cluster to start tracing wires and bam the ecu could hear me!

 

its not NATS because it would give you a code so you can rule that out.
check the ECM connector. Make sure the lever is snapped back before plugging it in then make sure its snapped shut after plugging it in.
also check the pins are soldered to the pcb where the connector plugs to. I was tipped off that sometimes the solder joint can go bad

 

Ok thanks everyone. I will check pins, remove cluster and anything else I can think of to see if i find any kind of short. One thing i forgot to mention earlier. I did find a blown o2 sensor fuse. i replaced it and no change

 

I had the same problem in my 2k 5 speed and went through hell figuring it out. I had lost my only key for it with a chip and was trying to use nds2 to program a new one. No communication with the ecu but nds2 was getting power as was my code reader. The car had been in a wreck before I bought it and the relay box behind the drivers headlight was smashed and the relays hanging everywhere. Hit a deer my 2k Gle and the same thing happened to that relay box. Ended up replacing ecm relay in that box and it clicked all of a sudden. Gle started having similar issues. Took the old relay apart and it was full of rusty water. Ended up learning the hard way if that relay box gets smashed which it will almost every time you have frontal impact go ahead and rig something up to stand the relays back up the direction they were and put something over them. Wouldn't hurt to glob some gasket maker on the bottom of the harness connector where the wires go in either. Check that relay. Good luck.

 

well its a good idea because if you have NDS and and cant connect its most likely something in between the data link and the chip in the ECM that feeds the NDS the info.
or that your USB com is not set right on your software.