Hello all, this is my first post so apologies in advance if I'm in the wrong place for posting.
Anyways I just got a 07 g35 Coupe and the front suspension was shot with the lower control arm bushing, ball joints, etc. Being blown out.
I replaced everything with all new parts and upgraded to poly bushings and just got it aligned. After the alignment and driving for a day on the way home my slip light started flashing and my front wheels started braking / grinding whenever the slip light was on.
I thought this was due to my dirt driveway an the VDC system reacting to it in a strange way. So I turned VDC Off and the slip light stopped flashing, and I made it up the driveway. So to be safe I turned the vehicle off and on, and once I did that now the VDC light stayed on also the ABS and slip light are solid.
My question is what this could be from, such as wheel sensor I disconnected when doing all the work? Or maybe it needs a steering angle reset? (Note I'm on aftermarket rims and coil overs, which were on the car previously with no issues.)
Also I upgraded to drilled rotors, also new pads. And the ABS does not make noise while the car is off. It seems when I brake while going slow the abs makes a grinding / springing sound.

 

That grinding sound is the ABS pump motor engaging the brakes and the car selectively opening solenoids for a corner of the car because it thinks it's sliding or spinning.

There's a LOT of things that can cause this but I would definitely start by just checking the wiring on the ABS wheel speed sensors that were unplugged.

Also definitely possible that the alignment changed the angle on the steering angle sensor and it might need to be recalibrated. Does the steering wheel track straight when driving? Did it change compared to before the alignment?

In the mean time to keep the ABS pump motor from turning on and killing a brake pad you can unplug the ABS motor relay, it's the big black box with 3 harnesses mounted to the back of the wheel well right in front of the brake master cylinder.

You will PROBABLY need your steering angle sensor recalibrated, sometimes the alignment shop will have the tool to do this, if not schedule a 1 hour diagnostic/appointment with Nissan and they can do it. You should also pull codes to see if there's a C#### code due to something broken on the braking controls system.

 

Appreciate it, that's what I was thinking as well just glad to have another opinion on the matter. I'll start with resetting the steering and go from there, I will stay updated here with if the problem if it has fixed or not.

The steering was way off before the alignment after I did the work to the suspension, after the alignment the steering wheel is now straight from what I can tell but I will have to double check.

 

Ahh yeah if it was a noticeable change then the steering angle sensor is definitely off. The car compares the steering angle to actual directional angle via the yaw sensor. If there's a difference between the yaw sensor and the direction the steering wheel is turned then it thinks the car is sliding or spinning and will try to correct.

 

Ah makes sense. I believe this is most likely the issue then, I will reset the angle sensor and keep updated. Is there anything to note about disconnecting the ABS system as you suggested? Such as maybe disconnecting the battery before doing so? Or anything like that?

 

No the relay can be unplugged hot. It's just a relay, no computer inside it. If it's going to be a while until you get it fixed I suggest taping the end of the connector with electrical tape, and put a couple strips of tape over the relay as well just to keep the connection free of dirt/dust.

 

Update The issue is now fixed. So I took it in the have the steering angle sensor reset, and as soon as I left the shop all the lights came back on. So I took it home with the abs relay unplugged and decided it was probably something with the wheel speed sensor since that didn't fix the issue. So I jacked it up ripped off the front wheels and checked the sensors, both of them were loose with one barely hanging on! Guess I forgot to tighten them down fully and just hand tightened them into position. So, I fully tightened both of them down, plugged in the relay and started it up. Low and behold all the lights turned off, so I know it was one of them causing the issue (Most likely the loose sensors) but possibly both issues were causing the dash lights / abs issues. But thanks for helping me figure it out everyone! Good luck to anyone with this problem in the future.

 

Awesome, glad you got it all sorted out.

I've forgotten to torque bolts in the past, nowadays I ALWAYS draw a line with a sharpie on bolts when I'm torqueing them so I can just look at it to verify it's tight. It's saved my *** a lot over the years. When you take bolts back off you can clean the sharpie off with a little brake parts cleaner.