I recently bought my buddy's nightmare of a 2007 G35S, and it's my turn to try to figure out what's going on here. The basic rundown of what happened, he bought this car about 4 years ago with the typical sunroof leak. Had the BCM replaced at the dealer, car ran and drove great for a couple months. Sunroof leak continues, fried another BCM. I put in a used one, programmed it, it was fine for another few months. And yeah, he never fixed the sunroof leak, but this time the transmission finished itself off, so it sat and got worse. Once we got the transmission in, the ignition would turn on no problem, but it wouldn't crank. I used a power probe and jumped the starter relay on the IPDM, and it cranked and started right up, ran fine. However soon, it did absolutely nothing when I put the key in the slot. It beeps, but nothing else. No activity when I press the start button.

I checked all signals on the BCM and IPDM, they are both receiving that the key is in the slot and the start button is pressed, so I don't believe there to be an issue with either of those. The ECM isn't responding since I can't get the ignition on.
When I command the ignition on through my scan tool on the BCM, it turns on fine. Fuel pump primes, etc.

I tried reprogramming the BCM and re-registering the key, however I get an error every time. I'm not sure if it's due to an incorrect immobilizer PIN or lack of communication (says to turn ignition on, but I can't).

When I CAN'T get the ignition on, I occasionally get a U1000 code on the BCM and meter (cluster). When I get the ignition on, I get the following-
ECM
P1610 Lock mode
P1611 ID discord- ECM-immu
P0603- backup circuit

BCM
B2193

IPDM
B210F- something about Park/neutral position, but this car is manual... no issue here, I know for certain that the neutral switch in the trans as well as the clutch switch are working properly.

Anybody have an ideas? I pulled apart all of the connectors at the ECM, BCM, and the two large junction connectors, cleaned them off, and sprayed them with Deoxit. Cleaned the ground above the glove box, and everything physically looks fine. Could a bad ECM be causing this and taking down the CAN network? Even unplugged, I still have the same issues. Plus as far as I know, the ECM shouldn't prevent the car from turning the ignition on, only prevent it from starting.

 

Well, BCM is the boss and controls it all. When i bought my car from neighbor across from me, it sat with a 10" deep puddle of water for over 2 years, it had mold on pretty much everything. The BCM was nice and juicy but after drying it, it worked fine for few months until the Yellow Key started to blink. I couldn't program the key fobs because my 'key slot' had green oxidation inside it and on it's pins and after cleaning it, it started to properly register keys. My push button also had mold inside and after cleaning, it works fine.

Since you said the car sat for a while, it probably developed oxidation is many places which the IPDM is not excluded from. That fuse box has a procesor which the BCM controls for all it's power needs. All grounds must be clean, the ones on the engine to chassis, chassis to battery, the battery must be 12.6 base voltage (i always connect a 15a charger during programming).

If you press the Start button with all keys outside the car, do you get the message No Key on the LCD?

 

After looking at those codes, it looks like the BCM is trying to tell the IPDM to turn on the ECM. Since you've unplugged the ECM and connected the battery, the BCM probably went in to security lock out mode (nissan special security) and will need to be reprogrammed to get it back on the same can network. The Start button is basically a ground switch for the BCM to turn the ignition on so i would confirm power to the BCM first, then grounds and if those are good, then get another BCM.


2007 G35 BCM
Not sure why a high quality, clear photo on my desktop uploads in this crap quality!

 

I will double check, but I don't think it shows anything if I press the start button without the key. They key battery is probably dead, since the remote buttons don't work anymore. The display on the cluster also has no working pixels, so I just get the orange back light, which only comes on at all occasionally. I'm almost thinking the cluster could be a problem, as the most recent check only shows a U1000 on the cluster. I occasionally see the red key light, but other times the cluster shows nothing at all. It's also worth mentioning that the key beep can get very distorted at times, and cut out all together. Tapping the cluster brings it back.

I did notice some green oxidation at the key slot connector, I sprayed that off earlier. I'll take it apart and clean the pins to make sure they're all making a good connection. I'm thinking the cluster may have gotten some water damage too, seeing as there's rust stains on the knee panel below the steering wheel (around the key slot area).

I normally tell people to stay away from water damaged cars like this, but I'm dumb enough to try to fix it since I like a challenge 😂


I agree that it sounds like a BCM issue though. However I have about 4-5 of them that I've tired to program, and none of them will program. I think it's due to the fact that I can't turn the ignition on, so it won't go through the programming process as it should. Same goes for when I try it with the ECM.

 

Cluster has no effect on security or ignition. I tried that with mine and i also had a dead LCD but was able to find one on eBay and just plug and play.
Key fob battery must be good and the key slot must be good as well since the BCM starts there. Put a new battery in one of them, stick it inside the slot (making sure it's all the way inside and locks) and press the Start button. Ignition should turn on with red key on the dash. That's how mine was after i unplugged the ECM with battery plugged it. If it don't, then check for power to the BCM and check the Start button if it grounds the Brown wire. Check the fuse links, check around the IPDM if rats or chipmunks didn't chew on wires..
As for the 'beeping' of the cluster, just ignore it as mine beeps whenever it feels like it so it's actually nice when it's not beeping. Check the plugs to the cluster but most likely, you'll need a used one.


Everything rusty behind the dash from the 10" of standing water inside the car from plugged up sunroof drains. The white stuff on the dash, that's yummy mold!

 

Noted... I did try to push the button without the key earlier, still nothing. Although the red key light was on this time. Probably because I still had the key slot unplugged from when I sprayed it out earlier.

I'm thinking I can't initialize the new BCM because of the wrong immobilizer code. However I'm having trouble figuring out the right numbers to put into the pin generator website. The digits don't quite line up on my BCM compared to their examples.

That dash looks the same as mine though, mold, rust and all! I'm hoping a good cleaning and a few rounds of ozone will knock out any and all mold... it's nasty stuff.

 

I ran an Ozone machine for an hour and had to wash everything out with clorox wipes, washed the carpet by removing it and the smell went away. Don't forget mold inside the AC evaporator core..
If you get the solid red key light, then you're on the right track. Next step is pin code and program. There are few sites that offer pin codes for free but my scan tools (xTool D7 and ThinkScan 689BT) provide the pin codes so key programming is no issue. As for ECM vin programming, i used Consult 3+.
Take that key slot out, clean it, inspect it, make sure key fobs got new batteries and reprogram. I heard that NDS3 programs keys and it pretty cheap.

The sticker on the BCM has a 5 alphanumeric number and i believe that needs to be inputted here to get the pin code.

 

Ah, I wasn't sure if that was a generic code or something. In that case, there's definitely still a communication issue. Both my Autel/Otofix tools provide the code, same with the my ThinkDiag. Putting the code from my BCM in that site brings up the same pin my scan tools tell me.

 

If that key slot is not working or key fob is bad, the BCM will probably not accept any codes? Or the BCM decided to crap out on you, it happened to me at random and I had to hardwire a separate positive wire to power up the aux fuse panel by driver's side kick panel.

 

I don't remember, I believe I checked power and had no problem with power or ground at the BCM. Worst case if this one's bad, I have like 4 or 5 BCMs for this car, so I probably have at least one good one. So basically what it comes down to, is that I can't program this BCM because I can't get the ignition on. Maybe it's a steering lock issue? I know that will brick these cars. But the steering lock (occasionally) works. This is so weird, because nothing is consistent with these problems.
The one BCM I have that DID run this car is likely bad, and while it let me turn on the ignition a couple times, it won't anymore. Not sure if maybe something is frying them one after the other or what.

 

The steering lock should unlock when a functional key fob is inserted into the functioning key slot during programming stage. Also, the car should be on life support (battery charger). Like the Jaguar, the JLR SDD software won't even connect to the car without external power source.
Check out post #7 of my BCM adventure where it tuned ON the driver side kick panel fuses for few seconds and then turned them OFF.
BCM ACC Power Bypass

 

Interesting.... I have a hard time believing I have 4 bad BCMs, but with my luck... lol.

I have it on a charger during programming as well. I'm hoping to have some time today to play with it a little more. I'm gonna start with a new key battery.

 

did you guys, by any chance mess with the TCM at all when installing the trans? https://g35driver.com/forums/g35-sed...reinstall.html

since it's a used trans, it may have been someone else before you messing with it and hooked things up wrong.

 

This car is manual, so no concern about that. Plus this issue started before we replaced the trans.

 

So I checked the ground terminal on the BCM (pin 13), it shows about 40 ohms to ground with the BCM connected. When I unplug it, it goes under an ohm. Not sure if that's normal activity or what. It is getting power at the main power terminal (pin 1) but not the "ign elec cont" terminal (pin 82), which is the accessory power output terminal, I assume.