Infiniti QX60 stops while driving

  • I don’t see an option to select QX60, and hence selected QX56.

I had driven over 30miles, exited the freeway, let go off the accelerator, neared a stop sign uphill - at which point I pushed the accelerator. I didn’t feel any accelerator/power at this point and hence moved the car to the side of the road with the left over moving speed.

  • I changed to reverse and tried to accelerate, which failed.
  • I moved to Parking and accelerated, at this time - it revved up.
  • I felt that restarting the car might help. So, I shut it down and when I tried to start it, it didn’t work. After one or two additional retries, I heard the clicking sound that was indicating that the car is being tried for start but wasn’t starting anymore.
  • Then did a jump start with the wiring being connected for like 20-30seconds, which worked. I did stop the car and then restart it, which worked fine.
  • Then I drove back home (about 20-30miles). Tried starting 2 times later in the day without any issues.
  • Next day went to the dealership for servicing + check, which they informed that no problems were found and that the battery was fine. This was about 5 miles each way.
  • Then drove for about 15-20miles, parked car for 2hours.
  • Started the car, put in reverse then into drive gave a little acceleration since it was parking garage. Then about 5secs later, pressed accelerator again - but this time it didn’t work.
  • A jump start worked fine (removed wiring in 5seconds/quickly) and was able to drive back home.

Now I am unsure when the problem is going to happen and what I should be doing.

  • The only time I ever saw the battery sign come up was when trying to start after it stopped while driving.

I tried to make sense of various blogs and posts, but couldn’t find what needs to be done.

  • If it was alternator, then a 5second jump start shouldn’t have let me drive home for 20miles. Even the 1st time jump start of like 30seconds let me drive over 20miles, then an additional 5+5 miles.
  • If its dead battery, then it shouldn’t after started after stopping it.
  • If its fuel injectors etc., then jump start shouldn’t have let me drive it.
  • Despite it being 90F-105 degrees, I don’t think it should have major problems for a V6 engine. Besides, a 5sec jump start shouldn’t have let me be able to drive the 20miles back with AC on the whole time.

Any help is appreciated.
Thanks!

Sudden, random deactivation of the driver-assist system , which can cause safety issues. Malfunction of the electronic control unit (ECU), which may cause random throttling or acceleration. Per online websites.

It might be a good idea to stop jumping this thing and have it towed to a good independent shop or even the dealer if one near you .

1 Like

I took it to the dealership again, they said they couldn’t find any issues.
The only error codes they found seem to be related to battery but that they seem to be old.

Ask your shop to remove battery, charge it overnight w/battery charger. Make sure battery fluid level is correct. Clean battery posts/connectors, reinstall, then do battery alternator system check. My diy’er version: Before first start of the day battery should measure about 12.6 volts, then immediately after starting engine, 13.5-15.5 volts. Until all that is done and the battery alternator test passes, suggest to not presume the problem lies elsewhere. A visual inspeciton ofengine compartment should be done too looking for obvious problme like loose connectors, corroded connections, etc. Esp check the ground strap connections between battery negative and chassis, engine and chassis, and cylinder head and chassis.

Not acquainted with your car, so no idea the difference b/t Q56 and Q60. Suggest to also post the model year and engine number.

Thank you.
I did the battery voltage check through multimeter. When engine is off, it showed 12.7+, while with the engine on, it showed 14.2+
The dealership said they did a test on the battery and alternator, and that they found no issues with it either. They said they checked for voltage reading as well.

They mentioned that as part of the 60k mile service, they did clean the battery contacts and replaced its pad - but I saw the corrosion solids yesterday after I got home with the jump start. When I mentioned it today, they cleaned it and I can see the new battery pads on the terminals as well.

I will check for the connection terminals you mentioned and see if I can find a loose connection.

Regarding the engine information, this is the link I can find from infiniti site: 2015 QX60 3.5L V6 CVT AWD PREMIUM Engine Parts | INFINITI Parts | INFINITI Parts & Accessories Online

Make: Infiniti
Model: QX60
Year: 2015
Other info: All wheel drive

The engine number is usually on a label on the underside of the hood, part of the emissions info the shop requires. I think what you’ve posted is sufficient for purposes here though. The battery voltage engine off and engine running looks good. I measure both at the battery posts and connectors sometimes, with the headlights on, so fairly big current is flowing. If there’s a difference in voltage could be there’s some undesirable resistance between connector and post. Sometimes a ground strap will appear ok at initial look, but if checked carefully there’s only two or three of the wire strands remaining, the other 15 have broken. Seems unlikely on a 2015, but if easy to check probably worthwhile. Engine work can sometimes inadvertently damage wires.

Is there a way for me to detect the connector issues? Any youtube video or some post you could reference me to?

Since the dealership couldn’t find the problem despite the diagnosis a second time, what we agreed upon is that, when the car stops while driving again - I would have it towed to them.

  • I doubt if this would help at all, because I suspect that any error codes if generate are being lost (based on the fact that they couldn’t find any recent error codes on the 2 diagnosis they did).

Below is what I noticed today for voltage readings:
Before starting the car in the morning: 12.63
After dropping kid at day care (about 3miles round trip): 12.60
Started the car to monitor voltage with alternator since it seemed low: 14.12 - dropping upto 14.09 in 30secs while the car was parked. The lights and ac were on at this point.
On stopping the car again: 12.63
Locked the car (to power off the auto-headlights and other internal lights): 12.72 - it was going up over a period of 30secs or so from 12.67.

Going to keep monitoring this before starting the car and after stopping the car for the next few days.

If the 12.6’s were when the engine was off, and the 14’s were engine on, those look ok. The diagnostic codes having been (possibly) erased indicates electric power to the drivetrain computer may have been interrupted. That could occur b/c of a battery/alternator problem, a battery connector problem, drivetrain computer connector problem, or faulty drive-train computer. Since it is easier to monitor the battery/alternator, you are right to continue that, and have the vehicle towed to the shop if the engine stops unexpectedly again.

Checking the connector at the battery post is the same method as checking the battery voltage, just probe the connector instead of the post. There should be little difference in voltage whether you are probing the posts (the round things) or the connectors (the circular things). The other connectors are harder to check, suggest to let the shop handle that. You might ask your shop to disconnect, then reconnect the drive-train computer, sometimes just doing that will clean up a faulty connection with one of the pins. Sort of like how you shake a flashlight to get it to light up again, which I have to do with nearly all my flashlights.

Stopped again today - roughly 100 miles driven (4 to 5 round trips from home to nearby places)
Todays drive consisted of:

  1. A 20 +20 mile round trip → was perfectly fine
  2. 30mins break
  3. 5 + 4.9 mile round trip → stopped when almost at home.

No lights on the dash like check engine, battery or anything else.

  • When I lost power, I moved to the side after trying to accelerate
  • Put the car into P(arking), gave acceleration. Tried to move the streering, but it was heavy → due to loss of power
  • Gave further acceleration to the car, then moved to D(rive)
  • Ran a feet or 2
  • Lost power
  • Stopped the car, lifted the hood and gave jump start with the one from Costco (8000 mAh)
  • Removed the jump starter, drove the car a couple of feet ~10-15? Had to do this because it was blocking most of the road
  • It lost power again. Likely because it was given from the battery pack and not a hard battery?
  • So I parked it, revved the engine in Parking for a few seconds → longer this time, since I wanted to rule out Alternator. I didn’t give another jump start this time.
  • Was able to drive the left 0.1 mile home without issues
  • Stopped the car, lifted hood and checked battery to be near 12.06V with multimeter
  • Started car, checked reading to be around 13.7V with slight trend towards decreasing (since AC was on and car was not being driven?)
  • Stopped the ac, then later the car. The reading was 13V+. Felt strange and so came back to check later (maybe 5mins) to find it showing 12.73V

I am suspecting it has something to do with the Electronic controlling circuits or the transmission (we received a notice about transmission warranty being extended a few weeks ago - something that dealership said they did check upon earlier this week when the car stopped for 1st time)

I have the exact same issue with my 2016 qx60. Have new battery and connection is good. Dealer said transmission was bad and they replaced it, but I am still having the same issue. They also changed the serpentine belt. I asked them to change the alternator at the same time, but they quoted 1700 and insisted that the current alternator is ok. I took it back and they said they can’t find anything wrong. I ran the car today with obd and torque program to monitor voltage. Voltage ran at 13.8 for 20 minute drive, got lunch and on the drive home it was 11.3 and dropped to 10.8 by the time I got home. I retested several times with the car in the driveway with no change. I disconnected the vvcs connect at the negative battery terminal with no change, reconnect with no change and then a short while later it went up to 13.3. Is it possible for faulty alternator to cut in and out, or should I be looking for other cause? I would.just.change the alternator out, but it is in a terrible location I’ve seen others with similar problem cut the control wire from the ipds to the alternator, so I’m considering doing that to test what happens. Any ideas would be helpful.

who paid for trans? you dont want to pay 1700 for alternator? neither would i.
new serp belt is $40. and new alt is $1700? bit of a difference.

Dealer cost is always expensive. 6k for the transmission and 300 for the belt. I would normally have just done the belt myself, but it’s my wife’s car and I just didn’t have the time to do it. Part cost for the alternator is 240 for the OEM from Infinity. Seems like it is a 4-5 hour job to change it due to the location. Last time I changed one was in a Suburban and it took 45 minutes at most. Car was working perfect today. It is just strange that it is so intermittent.

That’s an important clue. Immediately after shutting engine off after a sequence of fairly long drives, battery should measure 12.6 volts or above. 12.06 V means the battery isn’t being kept properly charged. Could be battery, alternator, or some circuit in the car is putting a big drain on the electrical system. You will probably need to get a dealership or inde shop with Infiniti technology specialist to help figure it out.

When I check my Corolla’s battery voltage immediately after a 10 mile drive, engine off, battery measures around 13.0 volts. Suggest you make a record of measured battery voltage immediately after driving, engine off. Might be helpful for your shop.