MakaiB74

I have a 2013 infinity g37 coupe automatic transmission. One evening I drove out of town to work without a single hiccup in the car approx 40 miles. On my lunch break I was letting the car run and both the rpm’s and mph gauges did a sweep all the way to the far right and almost every dash light came on so I figured eh it must be running some kind of system test. Since it was the end of my lunch I turned the car off and headed inside. Approx 4 hours later I start the car and the dash lights are still on, at this point I’m confused and concerned. I put the car in drive and start to accelerate and the car jerks forward as if the car can’t calculate when to shift. I pull over put the car in park and I notice my dash lights dim drastically I try to scan the car and my code reader is telling me it can’t communicate. I try to turn the car off and the car won’t shut off so I disconnected the battery and the car was still running so I pulled the ignition fuse and it slowly cut off. I got it towed home and attempted to start the car again and it doesn’t even attempt to start. The dashes lights aren’t as bright as they should be and when I press the ignition switch and the breaks the car won’t even attempt to start. If I put a new 50/30/30 fuse in the car the dash brightens up to normal and I get the door chime and I can start the car but then the lights dim and I can’t turn it off with the ignition button once again. I would like to note as soon as I turn the car to accessory mode my cooling fans come on and i my radio and ac and power windows seats etc all still work. Any ideas what it might be? I’ve seen someone with a slightly similar issue say their Ipdm was the issue but I would like second opinions before I go through with that. Also the nearest infinity dealership is 4 hours away so I’d like to repair it myself if possible.

falkon240

What's the battery voltage looking like?

needsoju

I recently experienced not same but some what similar issue. I had a situation where I was able to get the car started but couldn't turn off. Eventually it pointed to a bad BCM.

"code reader is telling me it can’t communicate", You need to try to figure out what's causing that. Fact that car can be started tells me that you can rule out engine/transmission and other mechanical components. There are fuse boxes on driver side, and two fuse boxes near the battery (one which is IPDM hard to access to). You could try to check if fuses are good to rule out any thing is out of ordinary. Then I think it would be safe to suspect if BCM Is good or not. See if you can use scan tool to access BCM. Even if you can access the BCM and you are getting communication error message, I think you have to suspect a bad BCM.

It's worth checking out if you see any moist Mine didn't have any water leak, but still turned out to have a bad BCM.
If Nissan dealer is some what closer, maybe you can ask if they can diagnose g37.

MakaiB74

12, the battery isn’t getting drained and I replaced the battery when the issue first arose a month ago. I also have one of those portable battery chargers/jumpers I’ve used it but it doesn’t make a difference with starting the car

MakaiB74

Annoyingly enough with the Nissan dealership I had called prior to getting my car towed over there and asked if they service g37s, they said they do so I gave em a brief rundown of what was going on and the first day they looked at it they ended up breaking the hood latch cable. They had my car for a little over a month to repair the cable and their diagnosis was telling me exactly what I told them when I dropped it off so no progress with them. Their ultimate advice was take it to infinity. I’ve replaced almost every fuse in the Ipdm and the lights illuminated for about 30 secs and then went back to the same no start scenario. I wanted to change the relay for the Ipdm as well but I’m struggling to find the one that I need. The one fuse that I did replace that seemed to make a difference was the 50/30/30 fuse it controls the ignition and two other things I’m blanking on what they are but after replacing that the car started and I was able to communicate to clear the false codes. The car drove like normal for about a day and then once again when parked with the car on for no more than like 10 minutes the lights dimmed and I wasn’t able to turn the car off. i also replaced a couple fuses that are on the driver side none of em blown but still replaced em for the hell of it still no change. I also replaced the battery terminal fuse didn’t change anything either.The last thing I need to check is the bcm you mentioned but I genuinely can’t remember the last time it rained. I’ll keep you updated thank you

needsoju

See if the symptoms similar as this here?
I was able to get my car started with scan reader also . For some reason when we hooked up the scan reader, we could start the car. Someone said that Scanner is bypassing and acting like function of BCM.

Also read this and see what the owner of G35 went thru It's very similar as you.
https://g35driver.com/forums/general...wer-all-2.html

I can't say for a certainty BCM is the issue but all symptoms and possible.
I would say if you want to invest say $275 or so you could try to send it off to BCM repair. https://www.g7computers.com They said if nothing wrong they will refund. I almost tried this but i didn't. The thing about BCM replacement is that you will need to get it reprogrammed (car setting plus auto key settings). So you will need to get to someone or infinite dealership to get it program correctly.
Can companies repair BCM? Well I also read in other forums for some make, they would utilize BCM repair shops too.

Search thru G35 forum also, and I also found many helpful posts as well.