Hello all,

I've been lurking around this website and forum for a while since I've bought my 2003 M45 a year ago (pristine (as much as a Canadian car can be anyway), not even 100k miles yet). About the car, it seems all maintenance was up to date before I got it. The 100,000kms tune-up was done (including change of diff and trans fluid) and all recalls taken care of. But, recently I've been having major problems with it which have prevented me from driving it.

Last summer, the car started stalling at random occasions while driving. I didn't get any DTC until a while when it stalled and all the dashboard lit up. The car went into limp home mode. I then got a P0605 code (internal control unit fault in the ROM memory - ECM fault basically). Additionnaly, I got P0507 (idle controle system RPM) and P1705 (throttle position sensor). I already had two codes at that time that I hadn't fixed yet: P0455 (EVAP large system leak) and P1488 (vent control valve). The issues were on and off but happened more and more frequently. Eventually, the car started to idle rough or simply not idle at all. I used my Bluedriver scanner to pull the codes. Unfortunately, it cannot read VDC codes.

Fast forward until December. I didn't have the time to fix the car as I had to move to a new city, university, work, etc (had to get the car towed for the move). After clearing the codes a few times, the only thing that was reccurent was the P0605. After reading from the shop manual (thanks NICOclub!), I proceeded with buying a used one from Ebay.

I bought Nissan Datascan II (NDS II) and a compatible cable. I had trouble connecting to the ECM, but it ended up simply being a software issue. The newest beta version of NDS II solved the issue. After resetting the ECM settings through the software, and with the help of the Nissan Supercode software, I registered my keys. I was all set. After starting the car for the first time in a while, it understandably idled roughly (also was -10 celsius or colder) for a few minutes and smoothed out. The VDC, ABS and TCM(not sure about the name of the third one) lights all lit up. I did the required learning via NDS II and tried to do the rest manually. I went for a few rides around the neighborhood. The VDC, ABS and TCM lights did not shut down and power steering felt only half present. BUT, the main problem - I thought - was gone: no more check engine light.

I ended up driving the car around roughly 100kms (60 miles) on a period of 3 days without an issue with the different warning lights on. The car didn't get into limp home mode once. Eventually, as I was driving home after a Christmas diner, the car stalled and shut down while entering the highway. Exactly like it used to do. The P0605 code showed up again. I waited on the should a few seconds and restarted the car. I was able to get home normally with still the VDC, ABS and TCM lights on (+ check engine light this time).

The battery was a bit weak on the car. So I went out and bought a new one. I cleared the code and went for a drive. Car stalled twice in less than 3 kms, and the RPMs were all over the place. Was a real struggle to bring it home safely.

That's where I am today. I'm not too sure on the step ahead.

Should I look into the codes I had before swapping my ECM? Should I get some scanner that can read my VDC, ABS and TCM codes? Should I get another ECM? Can I reset it to some factory configuration - my used one and my original one?

I really am lost here. Any help would be greatly appreciated! Looking forward reading your replies.
BTW, I tried to look for a non-dealer local shop that was specialized in Infiniti but couldn't find one. I live in Montreal, QC, Canada.

Cheers

There's a bulletin for P0605, ITB03-048:
https://drive.google.com/file/d/138KxgN ... sp=sharing

VStar650CL wrote: ↑

Fri Jan 28, 2022 1:24 pm

There's a bulletin for P0605, ITB03-048:
https://drive.google.com/file/d/138KxgN ... sp=sharing

Thanks for the bulletin.

I've gone through it but I never got a MIL following the use of the Intelligent Cruise Control. I did get some issues with it a while ago, but they were caused by winter road filth accumulating on the sensor or sundown light blinding the sensor. Furthermore, since my car seems to have been thoroughly dealer maintained through its life, I'm pretty sure the ECM would have had the update at one point or the other.

As my car is in my underground garage at the moment, I would have to get it towed to the dealership but i'd rather avoid the 150CAD hourly rate. M45s are even rarer in Canada than in the States, dealers don't have much if any experience on them.

Would you have any other idea regarding my issues?

Thanks

Found this post that could point out to the intelligent cruise control (ICC) being my problem:
Re: Trouble lights on dash came on VDC, ABS, Slip

"Postby Tolani2020 » Tue Jan 05, 2016 3:18 pm
If all of your lights come on, speedometer and RPM remains at 0, car jerks to switch gears , drives sluggish.,,its not the alternator, battery, starter ur ECM module. Its your cruise control laser. I have 05 QX56 its at the dealership and they disengaged the laser. To fix $1700+labor. It will throw a bunch of codes P0455 U1000 and some other internal codes. The laser is going out and is causing communication problems."

This is not what happened to me, but is not too dissimilar. I could try to disable the ICC as per instructions from the manual to see if my codes go away.

Also seeing low brake fluid causes the whole dashboard to light up too. Mine is full but I'll try to add some fluid just in case.

You asked for advice, and I'll share my opinion. This might sting a little, but I hope you trust that it is coming from a good place.

LeGrosRoger wrote: ↑

Mon Jan 31, 2022 10:59 am

...
As my car is in my underground garage at the moment, I would have to get it towed to the dealership but i'd rather avoid the 150CAD hourly rate. M45s are even rarer in Canada than in the States, dealers don't have much if any experience on them.

...

I know hindsight is 20/20, but if you were to be honest with yourself and tallied the costs you have incurred so far, adding the troubleshooting time and frustration, plus the uncertainty of interrupted trips; do you think it would have been cheaper to have a dealership diagnose the car for you?

As much as M45s might not be common, it is not a Nissan GTR whereby even in the Nissan network, a dealer has to be certified to work on it. An M45 is essentially a Nissan that can be troubleshot with the available Consult software.
If an independent shop, or even you, can read codes, swap parts and reprogram an Infiniti and make it driveable again, a dealer should be able to as well.

All this to say, please take it to the dealer. Even if the service scheduler you speak to might not have heard of a 2003 M45, I will 99% guarantee that somewhere in the service and repair network, they have a collection of information on it - whether that's a person or a set of documents.
In the US, most dealerships have a flat diagnosis rate, that can usually be negotiated if you choose to do the repair work there. Otherwise, you DO NOT have to pay the dealership rates to fix the issues they find.

Rip the band-aid, pay the tow + diag, and save time and money replacing parts and wishing/hoping it works.



***
Btw, I would look into membership tow services like AAA roadside assistance. Best investment I have ever made as a frugal person.

It stings, but you are entirely right!

I'm pretty much at the bottom of the barrel regarding what I can do with what I have under my hand. I've been thinking about it for a while, and I'll set aside some money to get it properly fixed. The car is worth it. I've contacted the dealers in my area and one of them seems more prone to help me fix my issues. I could also provide parts to them at my risks if need be.

I'm a gold member of the Canadian AAA (simply named CAA) already and I think I've got one or two service calls left for this year, so towing shouldn't be a problem. So, could get it towed back home if I decide on a DIY fix after diagnostic. Thanks for the advice!

On the bright side, after extensive research, I might have found a way to get access to a fully working Consult III-plus software on the cheap. I'll keep y'all posted if I get it working. I'm really curious to see how it goes.

Thanks for all the advices and I'll update my post as the situation evolves in the following weeks.

Any updates?

Shanemm wrote: ↑

Mon Mar 21, 2022 3:15 pm

Any updates?

Front left ABS wiring could be the culprit. The circuit is marked as "opened" by Consult III+. Did not have time to dig too much into it yet unfortunately. Currently in the middle of testing the continuity and everything.

Doing a brake job at the same time because why not.

Will post the results once i get more.

Shanemm wrote: ↑

Mon Mar 21, 2022 3:15 pm

Any updates?

Finally got some update!

Got it fixed mid-July after buying a new left front ABS harness (from Rockauto).
The Infiniti dealer's tech did not tell me what he did to fix it, but as far as I know he replaced the harness and did all the software resets and recalibration. Worked on it 4hrs at 180CAD/hr, was pricy but very glad he got it fixed. Tried to put in the harness myself, but the old sensor broke in the hub. Got it towed immediately after, I was over with it

Left for vacation the week after, and car started behaving badly again 3000kms after. Then, the issue was a faulty front crank sensor as is usual with these engines. My problem all this time might have been a combination of both issues, but never got the code for the sensor until much later once I was back from my vacation.

It's been good since.

Happy driving