typy01

When I picked it up from the dealers, they told me they were pretty certain it was a bad ECM, so as soon as I got it home I removed the ECM and have sent it back to the repair facility, SIA Electronics in IL, Who I have had NO problems with, and I'll be happy if it turns out to be the ECM is ok, although I hope not, I really want it to be plugged back in and run like a baby ! I can dream can't I ??

erhanyolcu

This is what i have done until now but i cant move on

M-train

iTrader: (3)

I'm having almost the exact same problem as you.

Engine died, and my scanner won't communicate with the ecm unless I scan in enhanced mode, by make, then I get a U1000, PO726 code ABS CAN malfunction.

I bought another ecm used as NIssan no longer makes my ecm, and took it to the dealer where they said it was bad. However I scanned it again at home using the "enhanced" mode on my Innova scanner, and got the same U1000 po726 ABS code.

Yesterday I installed yet ANOTHER used ECM, but this time I got the matching key, ignition switch, immobilizer [security], and ecm all from the same car.

I charged the battery, turned the key, and again the engine would crank, but not start.

So I scanned this newest ecm, and I'm only getting a U1000 code [still not able to communicate with the ecm unless specifically scanned by make, ie Nissan.

Here is what I would like for you to do.

Find your IPDM [my car is an 05 Altima SER so my IPDM is going to be in a different place vs yours].

Find the ECM relay. Pull the ECM relay out.

Now take a volt meter, and check the voltage in the empty socket holes. You should get battery voltage on two holes, and zero on the other two holes.

Next turn the key to ON, and take a reading of the other two holes. One hole should be batt voltage with the key on, and the other remaining hole should be zero.

Mine is getting normal 12v on two holes, and a mystery 9.8v on one hole with the key switch ON.

Here is my drawing of the empty socket, and what I'm reading on my ecm relay socket.



Check the hole labeled "C" in my drawing above WITH THE KEY TURNED TO ON, and see if you're getting anything less than battery voltage, and report back.

I want to see if we are getting the same problem EXACTLY as together we might be able to figure it out.

NOTE: The 9.8v goes out to just about everything including the coils, the crank/cam sensors, so I know that is definitely my problem. I just can't find where the switched 9.8v is coming from.

Cux350z

iTrader: (162)

there should not be any 9.8v power supplies, Something is drawing the power down.

Sounds likes yalls ecus are not getting 12v power. fans come on = ecu not talking.

M-train

iTrader: (3)

That is my point. There should be 12v on that pin when I turn the key on.

My fans aren't on when the key is on.

If I can find a wiring schematic for an 05, or 06 Altima V6 I might be able to trace where that switched 9.8v is originating.

Also, we don't know yet that the other poster is having the same issue with the pin on the ecm relay, as that is why I made the post above to ask him.

Hopefully, he will see this, check his voltage, and reply back.

dboyzalter

iTrader: (3)

Wow that looks horrible.

typy01

I have sent the ECM back to be checked and as soon as I get it back, I will check it and let you know.
I am about to the point of going with another option!! Call a JUNK YARD !! No not really but I am not going to let it worry me to death. But as soon as I get the ECM back I will check the 9.8 volts out and see if it is the same. That would be really interesting. I agree with CUX350Z there should be no 9.8 volts, but I have seen stray voltages on different things that used relays, and over the years it turned out being something had lost a ground and the lower voltage was just a static voltage, that was feeding back caused by the stray ground being gone. I am NOT very informed on car wiring as all my previous experience was in Medical Electronics, and many years ago the old Vacuum Tube computers and High Power Military Transmitters etc:, remember I am 84 years old and have to go slow !!

M-train

iTrader: (3)

Well, today I finally threw in the towel, and put the POS on craigslist.

The throttle body failed one of the diagnostics test so I replace it yesterday, thinking that it might be part of the U1000 code [last time I got a U1000 code it was only a bad cam sensor].

Nope the tb still won't open close with the gas pedal depressed. Strange thing is that fuel pump relay is clicking. I disconnected the fuel pump, but the relay is still clicking.

I put the NEW battery on the batt charger set at 40 amps, and the relay stops clicking, so WTF???

So instead of throwing even more f*cking money at this POS, I'm done. I'll bet I have 15k in this damned car FULL of new f*cking parts, and nothing to show for it.

The car ran fine for almost two years, and around 5k miles, then just dies coming to a stop sign, never to start again.

I can get the engine to fire by spraying starting fluid into the intake, but for some reason the injectors, won't pulse.

I am getting fuel to the fuel rail as I have a fuel pressure gauge/regulator that shows fuel pressure. I also checked and found 12v at the injectors themselves with the key on.

As for me, again, f*ck these newer overly complicated pieces of $hit newer vehicles.

I know I sound old, but I can go out into the garage tonight, and start ANY of my 7 hot carbureted hot rods, and drive them anywhere. They will out corner, out brake, and out run most any stock cars made today.

Only think keeping me from driving them daily is, of course, the wife who hates loud, cars.

And, of course, all seven cars are EASY to diagnose, and repair. No sleepless nights scanning thought a damned 1500 page shop manual like for my stupid Altima.

Oh, and having 300whp is somewhat of a holy grail for these cars, but even the lowest cid Ford engine I have is easily over 300hp, reliable, and waaaay cheaper to build, and maintain, as a damned headlight only cost around $20 vs the stupid $100 for a single bulb on the SER.

If you mod these newer cars like my Altima at some point you have no choice but to take it to the dealershit to have a used ecm reprogrammed. Get ready to immediately have every mod on your engine blamed for the current problem your having with said vehicle.

Sorry for the rant.

dboyzalter

iTrader: (3)

Well that story sucked.

typy01

Well, Mtrain, I fully understand your rave, My computer came back from the re-builder last evening and I put it on a shelf in the garage and ,if I feel like it, I will get started on it AGAIN next week. If the second rebuild does not work, I too will probably put it on Craig's list. But before I do I think I might get in touch with some of these Young Guys in
Tampa Florida and see what they think. this little Z car has over 100 K miles on it with never a problem before. My Grand Daughter loves it but if soon it doesn't start, IT IS GONE.

M-train

iTrader: (3)

I hear you.

If all you had to do was simply swap out the ecm, and turn the key I might try again. Since you have to tow the car to the dealership, and pay them either way [if the ecm is good, or bad] then IMO, f*ckit.

The only other solution I can tell you, or try myself, is to find a high mile, or wrecked, but running car with all of the options as yours [ie automatic, heated seats, etc], buy it cheap.

Then swap out the ecm, the ignition switch with matching immobilizer, and see if you can get the engine to start/run.

If it still don't run, then start swapping modules, one at a time until it cranks.

Lets say you swap out the ecm, etc from the other running car, and still no start.

Next you swap IPDM's, and the engine starts and runs great.

You then know it was a bad IPDM. You would then have the option to just keep driving the car with the use IPDM, or order a brand new IPDM from the dealer, and keep the known good unit as a spare for testing.

Lucky for both of us that these cars are now so old that there are many around for sale cheap.

So, if I don't sell mine I will just leave it sitting on the trailer until I have cooled off a bit, and decide find a cheap 05/06 Atima SL [the SL has most of the options of the SER].

Almost forgot. After you get it running, then sell it, and move on to something more reliable, if there is such a thing today.

typy01

The dealer put a new IPDM in mine when it was at the shop, and then
guessed it had to be the computer, so as I said in my last post, as soon
as I can get motivated I will give it another try. The re-builder told me it
would not affect the ECM settings when they repaired it, but who knows.

Atreyu'z 350

Can't understand your problem since there is no explanation of a problem. You want us to just guess, cause we can..?

JasonMcneal

Hey guy's just need some quick answers while I wait for a ride. Seems my key immobilizer decided to turn on out of no where. So I have NATS disabled (thanks uprev for helping late night) and I've already had a locksmith come to try to reprogram a new key. Now I've had to locksmiths come and neither could fix the problem. They said there's a "communication error" but the BCM is working. My fans don't kick on, and this damn red light isn't going off. (Reminds me of the horrible old Xbox red ring of death&#128514 Any suggestions or insight would be awesome.

M-train

iTrader: (3)

Isn't on board security fun. I hate these cars.

CK_32

iTrader: (1)

God that's an ugly engine bay.

That almost looks like it was under mud. Sorry about your troubles OP. Never buy someone else's project car. Hopefully you come back to the Z club with a proper non jacked up Z.

typy01

Jason, My 2005 350z started somewhat the same way,
now $2000.00 ++ and 2 ECM's and one IDPM later,
3 tow bills, many many hours work, and the damn thing
still won't run. My fans come on when the switch is turned
on and that is it, In all fairness, when I had it towed back
from the Nissan Store where they told me it was
the ECM and they could not get one, I had it re-built
and they had put a new IDPM in at the Nissan Store and said everything was ok with the exception of the ECM.
When I put the re-built one in, fans did NOT come on,
and tried it, momentarily it acted like it was going to crank,
but did not. I said to hell with iit and am considering selling it as is.

M-train

iTrader: (3)

That sucks to hear. If it helps you're not alone.

I just checked out my CAN bus diagnostics as per the Nissan shop manual.

The only thing that didn't check out was the gauge cluster can wires which should have read [per the shop manual] 54-66 ohms, but instead read 120.

I tried to find the connection were those wires connected to the main can line, but the damned wires went into the main wire loom which went behind the AC/heating ducts. The whole damned dash would have to be pulled, and the main bundles of wires would have to have all of the electrical tape taken off to find the connections.

I checked continuity of those wires at the approriate spot on the DLC, and it was fine so I'm going to say the can buss wiring/connections were good.

Anyway, I don't know why I'm still getting that damned U1000 code with three different ecms.

Today I got another matching ecm/key/immobilizer setup, but I'm going to wait until tomorrow to give the engine another/last shot to fire up.

At some point you have to just throw in the towel as these newer cars just aren't meant to be repaired like the older cars of the 60's/70's, and early 80's.

Heck on the older cars in those years, you could get away with modding the engines, deleting parts, etc to make the car run better, but damned these new cars are too integrated with parts intertwined with everything else.

Plus the damend engine control manual for my car alone is over 1400 PAGES, and that is just the engine control manual, there are about 20-30 more manuals left [most aren't as long as the engine manual, but some are longer].

Who the f*ck is going to be able to know all of that $hit?

Last your at the mercy of whatever deal$hits you take your car to have reflashed actually knowing wtf they are doing, IE shop FOREMAN thought I was nuts for putting NOS on my Altima. I asked him to show me the NOS, he pointed to the adjustable fuel regulator, fuel pressure gauge, and catch can, what a damned idiot he was, and he was the FOREMAN/HEAD MECH.

M-train

iTrader: (3)

Update on my problem. I think I have it repaired, well all except taking to the damned dealershit to have a new master key made.

This is a copy/paste from my thread on another forum so it will be in parts.

Part 1.

Now for the interesting part.

I decided to go back, and try to make sure the wiring connector still held tension on the female side.

So I started with the DLC conn. I pushed all of the female pins back in [I really don't know how to explain this without going into detail].

Then I decided to try a scan, well the scanner was able to communicate with the ECM, and I got a list of codes. [for some reason now the dash gauges don't light up with key on].

Here are the codes, I erased them as they could have been stored by the used ecm, and scanned again.

PO462-Fuel level sensor circuit low [might have to do with the gauges not working, not the fuel level sensor as the fuel gauge was working at the start of this week]

P0-463-Fuel level sensor circuit high imput [same as above]

P1610- VATS lock mode. Unable to reset without registered key [Again Doug, I'm guess that means the transponder key, not the valet key]

P1800- VIAS control solenoid open [I disconnected the VIAS as I no longer need it]

U1001-CAN malfunction, Invalid or Missing Data for Primary Id, which could mean bad ecm, or Harness or connectors (CAN communication line is open or shorted)

P1726-Faulty Throttle Body Throttle Body harness is open or shorted Throttle Body circuit poor electrical connection. The TB is new, and is actually working, so I'm going to look at the connector.

M-train

iTrader: (3)

Part 2.

I cleared all of the codes today [except for the SRS, and the NATS].

A few things here. Apparently, the battery was a little low which is why I got the sub 12v on all of the fuses on the IPDM.

1. The EGR valve was pulling power down just a bit, so I removed it. [there is no valve left as I have header, but the electrical part was still there, for which I tried the resistor trick, and it made the car run crazy so I took it off, and reconnected the electrical part of the egr valve.

2. There was a loose connector in the dash fuse box causing the gauges to go out, which I didn't plug back in when checking the CAN bus.[Fixed]

3. The female connectors going to the throttle body were opened up too much so I took them apart via instructions from this video.

4. The sun happened to be at the right angle showing me the male terminals on the ABS connection, which were all green [mold/corrosion].
I took some sand paper, and cleaned them up, and then used a metal nail file to clean up the female connectors. I also relocated the ABS ground to a place more accessible on the frame.

5. The SRS codes are still there stored, but I got the blinking air bag light to stop blinking by doing a reset on the SRS [key on, key off, kinda thing].

Now it looks like the only thing holding me up is the damned NATS, as they are the only codes I getting.

I would just send the whole ecm/key/immobilizer back to the Ebay seller as I paid premium money for matching related parts. However, since all of the codes are cleared, it looks like this ECM is good, so I really don't want to mess with anything, as first, those ecms are hard to find, and finding an ecm that actually works is even harder.

UPDATE: I was able to get a partial refund from the ebay seller [thanks rv] for the ignition switch, immobilizer, and valet key.

So it looks like all that is left is to take the car to the dealer to have a new master key made.

Here is a question. My old key fob from my car still works the door locks, but I got the key fob that went to the new ecm so how will they work that out at Nissan?

I figure I need to know this as they may not.

Would it be best just to have a new master key made, then have the bcm reprogrammed for the new key fob? Is there any way for them to reprogram my old key fob?