Part 2..........

Our next mistaken identity vehicle is a 2005 Infiniti G35 coupe with 61,304 miles on it. Vehicle originally came in for state inspection with the MIL lamp on and many codes. The shop was able to correct many of the issues. They did however have a couple of codes that they could not rectify and the MIL lamp is still blaring away. In New York state if the MIL is on the vehicle will not pass its annual inspection. Ok, lets start by hooking up and seeing the codes and some data. Remember, to click or double click on pictures to make them bigger.

Here, I am using the Nissan Consult 3 scantool. I have a love/hate relationship with this scantool. I love this tool but it is glitchy and has a steep learning curve. It is not very intuitive. When you hook up it will do a VIN check and what is called a system call where it reaches out to see what modules are on the vehicle. The VIN function will be active on 2005 model years and up. It is retrieving the VIN information from the PCM/ECM. I notice something right away here. The VIN on the tool is not the vehicles VIN. I smell some swapped parts. Let's pull codes.

I pull some airbag codes. Yes, the airbag lamp is on and no it is not part of state inspection so the shop owner nor the vehicle owner is concerned about it. The ECM codes are what is putting on the MIL lamp. The P1564 will not illuminate the MIL. By the way ASCD stands for Automatic Speed Control Device in other words cruise control. Given the airbag codes presented it is a good bet this vehicle has a bad clockspring in the steering column.
Now on to the codes that are putting on the MIL. U1001 and U1000. These codes are very common on Nissan/Infiniti vehicles. In fact there is a TSB concerning these codes with certain Freeze Frame data to basically clean all the vehicle grounds. Including the ones on the interior dash support which requires taking half the vehicle apart. I check the Freeze Frame data and it does not match the criteria to clean all the grounds. CAN stands for Controller Area Network. This is a communication data buss that is very common in many vehicles. It is very fast and capable of supporting many modules quite easily. My experience is when I see these codes the module broadcasting these codes is not "seeing" a module that it should. The Consult 3 has a great tool for CAN diagnosis.

This function called CAN Diagnosis Support Monitor is one of the reasons I purchased this tool.
Here I am looking at what the ECM is seeing on the CAN line. OK means it is recognizing and Unknown means it doesn't see it. Looking at the data I can see that TCM (Transmission Control Module) is Unknown. This vehicle is a manual transmission vehicle. This would make sense because this manual transmission doesn't utilize a module. But wait....Something smacks me in the head.

I decide to look at the calibration in the ECM. I run this part number in the Infiniti programming database. By the way NASTF.org will have all the OE websites listed.

This calibration is for G35 coupe with an automatic transmission not a manual. Bingo. That is the reason behind the CAN codes. The ECM is looking for a TCM that is not there. Not seeing it sets the codes and puts on the MIL.

To confirm my theory I drop the ECM down. Which was hanging in by one nut and it has salvage yard writing on it. I advise the shop owner of my findings and tell him he has the option of a used ECM but it has to be the right calibration. A new ECM is pricey. He has to consult with the customer who has already spent a decent amount on this vehicle.

I get a call a couple of days later from the shop owner. A used one is nowhere to be found. A quality remanufactured ECM is not available as well. The customer decides to go new. This is a very pricey ECM. The first thing I do is run this number to see if the calibration is correct for this vehicle.

Looks like we have a winner. The next thing I do is plug it in and check the calibration through the Consult 3. Because, mistakes can happen in packaging.

Looking good. Now, we have to learn the NATS (Nissan Anti Theft System), write the VIN, clear codes, and run a IAVL (Idle Air Volume Learn) routine. Lets get started. But lets check codes first.

No more CAN codes. The P1564 code stays but will not affect MIL operation or prevent this vehicle from passing state inspection. Lets learn some anti theft.

 Since this vehicle was receiving  a new ECM it is in a auto program mode. It will learn the key without any special procedures. If this was a used or remanufactured unit the following procedure would need to be done in order to learn the NATS. I included the procedure here. First step is to go into the NATS section of the Consult3. This NATS setup requires me to retrieve a 5 digit pin from the BCM then convert it into a 4 digit pin to perform initialization and learn keys. I retrieve the PIN using the PIN READ function.

Before I had this tool I would have to unearth the BCM and try to read the 5 digit PIN on a sticker on the BCM. Not so bad on an Altima or Maxima. Try a Quest. Anyway, now I have the 5 digit code. I use this 5 digit code into a Nissan converter that gives me a 4 digit PIN I can use.

 
I go into C/U (Control Unit) INITIALIZATION screen and input the 4 digit PIN.

Initialization is complete. But, we are not done yet. We have to actually learn the keys or keys. Consult your service manual for the logistics of this procedure. After we do this the vehicle starts and roars to life. Now we have to learn the VIN.

Using the WORK SUPPORT menu I choose VIN REGISTRATION. This procedure requires entering the VIN twice. I always use capitals.

I complete the procedure which includes a series of key offs and key ons. The next thing I do is close out the application and reboot the Consult 3. I want to see if it pulls the the correct VIN during system call.

Nice!!!!! Now we warm up the vehicle and perform the IAVL routine. Recheck for codes. I tell the shop owner the vehicle is ready to be driven to set emissions monitors. I recall the shop later that day and the shop owner informs me that the vehicle passed inspection no problems.