Nissan 370Z Forum - View Single Post

ShadowJester6 · 04-10-2021, 06:36 PM

Greeting Pals,

Recently tuned the Z with a custom tune (remote tune). Car was in the garage. I started it up and drove it out to the yard so I could sit in the sun while I got the ECU flashed. Tuning process was superb and tune was flashed onto the ECU with no issue. All was right in the world until I went to start the car and get ready for some data logging fun. But alas, car did not start. Did not even try to turn over. Nothing. Welp, that's no good. Contacted tuner and we went over some troubleshooting. We went back and forth between custom tune, original OEM tune, older version OEM tune, and custom tune with NATS disabled. No change. Every time the start button is pressed, car will flip past "acc" to "on" as normal. But starter doesn't crank. Car just remains in "on". So tune doesn't seem to be the issue. Below are more troubleshooting steps I've taken with no joy:

1. Battery in FOB was fine, but replaced anyways. Tried starting with FOB in and out of the key port. No luck.
2. Car battery was on a tender the whole time during the tuning process. Voltage was fine with and without tender. Replaced battery anyways. I also left the battery disconnected a few times, including overnight, in case a relay or something was hung up. No luck.
3. Looked into the wheel lock problem that was a big deal with the older 370s. I have a '13 NISMO. They apparently stopped putting the ESCL modules in the cars around '11. Verified the module was not under the steering column. Verified the fuse was non-existent in the IPDM E/R fuse box. No luck.
4. Toyed with the clutch interlock switch (neutral safety switch). Tested the switch with a meter; open when disengaged and nearly no resistance when engaged. Test SAT. Looked at the switch in the tuning software. It toggles open and closed appropriately according to ECU. For science, I also tried starting the car with the switch disconnected and the harness side connector shorted out. I also tried combinations of the switch used normally and the switch shorted while disconnecting the cruise control switch at the top of the clutch. More than enough evidence that both switches appears operational. No luck.
5. Verified that the starter control relay was good with a meter. Relay audibly closes when start button is pressed. For science, I replaced the starter control relay. No luck.
6. Used a meter and tested every single fuse and relay I could get my hands on. Not a single component was faulty.
7. Tuner was kind enough to send me another ECU even though mine shows no signs of not being operational. New ECU, same issue. No luck.
8. Followed the FSM flow chart for failure to start. All tests were SAT (even with old battery). Resorted to the tried and true method of giving the starter a few wallops in the event that it was seized up. No go. Removed the starter and took to auto parts store for testing. All tests SAT. No luck.

I'm at a loss about what else I can try. If I follow the the system diagram for the starting system, I have have eliminated all but two (really three) options:

1. The starter relay, not to be confused with the starter control relay, appears to be integrated into the IPDM E/R fuse box. That would be a real drag to swap out that whole thing. But options are running thin.
2. The BCM. Apparently it's in the cabin next to the fuse panel under the driver's side kick plate. Also lame if I need to start toying with that thing.
3. After those two options, the entirety of the start system will allegedly be tested/fixed/replaced. Although highly unlikely, the wiring harness itself may somehow just gave up on life.

After tuning these are the DTCs that I have been able to pull:

1. Using the tuning app/OBD dongle, I have a HVAC2 "U1000-00" (appears to be CAN lost communication) code after flashing ECU. Code returns after clearing.
2. Using the tuning app/ OBD dongle, I have a BCM "B26E8-00" (appears to be clutch interlock switch) code after flashing ECU. Code can be cleared and stays cleared.
3. Using a generic app/different OBD dongle, I have a permanent U1024 (also appears to be CAN comm circuit/VVEL related) code after flashing the ECU. Permanent code cannot be cleared.

Although it does point at a generic wiring harness fault, I don't believe that the harness suddenly got disconnected and/or broken somewhere at precisely the same time I first flashed the ECU. If that was the case, it would also be unlikely that I could continue with more flashes and complete all the tests I have with no errors or more DTCs.

So that's where I am with my very fancy and very expensive paperweight. I was hoping that one of you might be able to chime in with something that I may have tested wrong or another component that may be at fault. I will totally bribe anyone that can help me find a solution for this car with a burrito. Thanks in advance for anyone that can provide any advice or insight.

04-10-2021, 06:36 PM	#1 (permalink)
ShadowJester6 Base Member Join Date: Dec 2015 Location: Oregon Posts: 23 Drives: '13 370z NISMO - MT Rep Power: 9	Car will not start after tuning Greeting Pals, Recently tuned the Z with a custom tune (remote tune). Car was in the garage. I started it up and drove it out to the yard so I could sit in the sun while I got the ECU flashed. Tuning process was superb and tune was flashed onto the ECU with no issue. All was right in the world until I went to start the car and get ready for some data logging fun. But alas, car did not start. Did not even try to turn over. Nothing. Welp, that's no good. Contacted tuner and we went over some troubleshooting. We went back and forth between custom tune, original OEM tune, older version OEM tune, and custom tune with NATS disabled. No change. Every time the start button is pressed, car will flip past "acc" to "on" as normal. But starter doesn't crank. Car just remains in "on". So tune doesn't seem to be the issue. Below are more troubleshooting steps I've taken with no joy: 1. Battery in FOB was fine, but replaced anyways. Tried starting with FOB in and out of the key port. No luck. 2. Car battery was on a tender the whole time during the tuning process. Voltage was fine with and without tender. Replaced battery anyways. I also left the battery disconnected a few times, including overnight, in case a relay or something was hung up. No luck. 3. Looked into the wheel lock problem that was a big deal with the older 370s. I have a '13 NISMO. They apparently stopped putting the ESCL modules in the cars around '11. Verified the module was not under the steering column. Verified the fuse was non-existent in the IPDM E/R fuse box. No luck. 4. Toyed with the clutch interlock switch (neutral safety switch). Tested the switch with a meter; open when disengaged and nearly no resistance when engaged. Test SAT. Looked at the switch in the tuning software. It toggles open and closed appropriately according to ECU. For science, I also tried starting the car with the switch disconnected and the harness side connector shorted out. I also tried combinations of the switch used normally and the switch shorted while disconnecting the cruise control switch at the top of the clutch. More than enough evidence that both switches appears operational. No luck. 5. Verified that the starter control relay was good with a meter. Relay audibly closes when start button is pressed. For science, I replaced the starter control relay. No luck. 6. Used a meter and tested every single fuse and relay I could get my hands on. Not a single component was faulty. 7. Tuner was kind enough to send me another ECU even though mine shows no signs of not being operational. New ECU, same issue. No luck. 8. Followed the FSM flow chart for failure to start. All tests were SAT (even with old battery). Resorted to the tried and true method of giving the starter a few wallops in the event that it was seized up. No go. Removed the starter and took to auto parts store for testing. All tests SAT. No luck. I'm at a loss about what else I can try. If I follow the the system diagram for the starting system, I have have eliminated all but two (really three) options: 1. The starter relay, not to be confused with the starter control relay, appears to be integrated into the IPDM E/R fuse box. That would be a real drag to swap out that whole thing. But options are running thin. 2. The BCM. Apparently it's in the cabin next to the fuse panel under the driver's side kick plate. Also lame if I need to start toying with that thing. 3. After those two options, the entirety of the start system will allegedly be tested/fixed/replaced. Although highly unlikely, the wiring harness itself may somehow just gave up on life. After tuning these are the DTCs that I have been able to pull: 1. Using the tuning app/OBD dongle, I have a HVAC2 "U1000-00" (appears to be CAN lost communication) code after flashing ECU. Code returns after clearing. 2. Using the tuning app/ OBD dongle, I have a BCM "B26E8-00" (appears to be clutch interlock switch) code after flashing ECU. Code can be cleared and stays cleared. 3. Using a generic app/different OBD dongle, I have a permanent U1024 (also appears to be CAN comm circuit/VVEL related) code after flashing the ECU. Permanent code cannot be cleared. Although it does point at a generic wiring harness fault, I don't believe that the harness suddenly got disconnected and/or broken somewhere at precisely the same time I first flashed the ECU. If that was the case, it would also be unlikely that I could continue with more flashes and complete all the tests I have with no errors or more DTCs. So that's where I am with my very fancy and very expensive paperweight. I was hoping that one of you might be able to chime in with something that I may have tested wrong or another component that may be at fault. I will totally bribe anyone that can help me find a solution for this car with a burrito. Thanks in advance for anyone that can provide any advice or insight.