Well i've been working on this for a longggg time. Im finally making this thread ive been meaning to for a while I really should of from the start. This is a big deal for us 5.5 genners. I need help tho, id really like to see this fully working. So I KNOW there are some great people on here, lets see if we can make Maxima History!


Background, UpRev is the company that makes Osiris, Osiris is a program that is flashed onto a Engine Computer (ECU). Then with Osiris on a ECU you can Tune the ecu to do many different things that are not possible before. This is done through their software, and a obd2 to usb cable.

I have the Full version of Osiris, the Tuner version. That includes one flash license and all features and my own obd2 to usb cable.

Osiris Features:

Up to 5 maps on cruise control
Speed Limiter control
Rev Limiter
AFR Targets
Ignition Timing Advance
MAF transfer function
Injector Latency
Intake Temp
Minimum effective injector pulse with
idle rpm
Electronic Throttle Control to acheive WOT at all speeds
DTC Disable
Fuel Compensation
Cam Phasing
Cranking Enrichment and Ignition Advance
K Fuel Multiplier
Calculated Load vs RPM
And NATS disable IMPORTANT for ECU swapping!!!


So all in all Osiris is really like a piggyback tuner system that uses the stock ECU. Sweeeeet Right?

So how do you get osiris into the 5.5 gen max??? WELLLL the stock 5.5 gen ECU does not support osiris. ahhhh failllllllll. My plan was to completely swap out the 5.5 gen ecu and run a Newer style ecu that osiris works with.

What ECUs does Osiris work with? That would be for the most part the ecus that have the BLACK connector YES YES that infamous BLACK ECU connector that totally SHUTS THE 5.5 gen out of all tuning options. 2004 + Maxima, 2005 + Altima, All 350Z, Most G35's thats the main ones.

Here is something important. 5.5 gen maximas have Factory NARROWBAND o2 sensors, only the 2003-2004.5 350z and G35 have this also. SO these ECUs can work with factory maxima o2 sensors, IF you get a ECU that came from a car with FACTORY WIDE BAND o2 sensors which are a huge advantage when tuning with osiris. YOU WILL NEED A AFR to TUNE WITH. I'm still experimenting with Narrowband vs Wideband ECUs and which to really use. Right now i do NOT have a answer as to which is the best to use.

OK moving along. Ive got a ECU now, Now ive made a Harness that adapted my maxima ecu harness to the NEW BLACK ECU i have. Wow i wish it was that simple plug in this harness and use the new ecu and bam your tuning! Well its FAR FAR FAR FAR FROM that easy!

Differences between 5.5 ecu and Black connector ecu: The numbers is the pin location in the harness.

5.5

18 Sends Coolant Temp to gauge cluster as 0-12 volts
21 Controls the AC Relay
24 and 24 are for Cruise control LAMPS CRUISE AND SET
30 AC Cut signal
33 MIL (check engine light)
34 Tachometer output to gauge cluster
35 Cooling fan low
36 Cooling fan high
45 AC Swith signal
64 APP sensor 2 power supply 2.5v
68 Vehicle speed sensor


These are things that the Black ecu does NOT support. The Black ecu does things a little different

It sends coolant temp , cruise control, MIL, Tach, and speed sensor over CAN lines, that’s CAN High and CAN LOW.

It also does not control the AC at all. This Is done through the BCM.

The Maxima APP sensor 2 uses 2.5 volts as power supply rather than 5 volts. Why I have no idea, but the black ecu does not supply 2.5 volts to app 2. just 5 volts to app1 and app2.

So the question is using the max ecu to control those few functions and black ecu to run the motor. Is that insane? Is that too much trouble? Is it possible? It is kind of crazy to use 2 ecu’s in one car. But someone’s gotta try it!!!!

So what I done to start with was. Made a harness that used the 5.5 ecu to control only those few functions that where needed. I used the Black connector ecu to run the motor basically at that time I was using a 03 350z ecu. It worked pretty good. One main issue was Coolant temp. If I had the coolant temp sensor hooked to the maxima ecu the rad fans would work fine, and the 5.5 temp gauge would work right. BUT the car would run badly due to the black ecu not knowing engine temp. So if I hooked to the black ecu it ran good but not fans and no gauge worked. AND if I hooked to both it changed the resistance of the coolant temp sensor and it made the gauge read wrong so the fans never came on and the car ran like crap. I believe if I added a second coolant temp sensor that would be solved. One sensor for each ecu.

Well after that there was another problem, if was driving and came to a stop the car would cut off every time. Just die out, I realized it was because the black ecu did not know how fast I was going. No speed input. BAD NEWS the black ecu only receives speed input from CAN Lines from the gauge cluster. Well 5.5 max cluster does not touch CAN at all. So I got a gauge cluster that uses CAN. The one that actually fits in 5.5 max is from a SENTRA. But it’s a 4 cyl, so I don’t think the TACH will be correct but I haven’t even tested it yet. IT SHOULD work just fine from the research. Then I though maybe I can ditch the 5.5 ecu if im going to swap clusters!

So Currently this is where im at:

Sentra gauge cluster, working on a speed sensor to give speed to the gauge cluster.

Ive got a 04 maxima ECU that has factory widebands, haven’t fully hooked them up yet.

I’ll need to find a aftermarket cooling fan controller, I don’t that that will be too bad.

I need to supply APP 2 2.5 volts OR SWAP to a different Pedal Position sensor.

Need to figure out AC functions and how to do them without the 5.5 ecu.


Conclusion, ive about gave up on this, due to it’s a LOT LOT of work. Meanwhile I could of got a Haltech, made a patch harness and had it working easy. And haltech is top of the line. Thing about it is the pricetag. BUT im figuring out that for the 5.5 gen a ECU swap that allows Osiris is really not feasible, it might be worth it to just buy a haltech. I haven’t gave up yet tho! Ultimately id like to get this working without using the 5.5 ecu. I need HELP. I know this post is probably confusing and not clear. Im much better at just talking rather than getting my thoughts down on “paper”. I do believe this type of swap would be IDEAL for swapping a VQ35 into a car it didn’t come stock in. like a 4th gen 3rd gen. Then you would have full tuning , AND could disable NATS so you could use your original ignition key