Is anyone else getting surging when going down hill with the cruise control set? I have the tech package with the auto cruise but it does it in regular cruise mode also. I'm having the dealer look it over when I get my next oil change and hopefully its just something that needs to be adjusted but it can't seem to stay off or on the gas when going down hill. Anyone else experiencing this? I found it most apparent on rolling hills, haven't had it on any steep grades yet...

 

On a steeper hill by my house it's not able to hold the set speed at all, the speed limit is 70km/h so I set it to 80km/h and by the time I was half way down the hill the car was going about 90km/h. I've had cruise control before but never really used it except on the highway (maybe 2% of my driving), so I just assumed this was normal.

 

I have the same problem when going downhill with the cruise set. It does surge on and off as if the car is trying to keep the exact set cruise speed. Very weird. You can even punch up the mpg horizontal readout on the center display and you'll see it go back and forth with each surge.

I've owned quite a few cars and I used cruise control in all of them, including an 03 G35 sedan, and I've never had this happen before.

Wonder if Inifiniti is looking at this as a technical problem...

Please comment if you have the same issue. Set your cruise on a hill going down. See if it happens...

 

I have this, and have read that many others do also. I would be interested to hear your findings from the dealer.

 

I would like to hear the dealer's take on this too.
This 'issue' is one of the more annoying things about anotherwise great car.
I usually keep my foot 'resting' on the throttle on downhill sections but then that defeats the reason for cruise control doesn't it?

 

Yeah, the controller for going downhill kind of sucks. To aggressive slowing down, and then it has to speed back up. I'm not sure if the dealer can do anything about it, unless a revised controll software comes out. It is annoying...

 

I've seen this behavior as well. The following from SM doesn't really help but I'll post anyway. I'll post the Cruise diagnostics mode as well.

DRIVING FORCE IS HUNTING
< SYMPTOM DIAGNOSIS > [INTELLIGENT CRUISE CONTROL]
DRIVING FORCE IS HUNTING
Description INFOID:0000000000965487
The vehicle causes hunting when the ICC system is active.
Diagnosis Procedure INFOID:0000000000965488
1.PERFORM SELF-DIAGNOSIS OF ECM
1. Perform self-diagnosis of ECM.
2. Check if DTC is detected. Refer to EC-521, "DTCIndex".
Is any DTC detected?
YES >>GO TO 3.
NO >>GO TO 2.
2.CHECK ICC SENSOR INTEGRATED UNIT BODY WINDOW
1. Check the vehicle driving conditions. Refer to CCS-104, "Description".
2. Check ICC sensor integrated unit body window. Refer to CCS-104, "Diagnosis Procedure".
>>INSPECTION END
3.REPAIR OR REPLACE APPLICABLE ITEM
Repair or replace applicable item identified by the self-diagnosis result.
>>GO TO 4.
4.CHECK ICC SYSTEM
1. Erase DTC and perform ICC system action test. Then perform self-diagnosis of ICC sensor integrated
unit. (For the details on the ICC system action test, refer to CCS-11, "ACTION TEST : Special Repair
Requirement (Vehicle-To-Vehicle Distance Control Mode)").
2. Check that no abnormal condition is present in the ICC system.
>>INSPECTION END

 

Cruise Control Diagnostics Mode:


ON BOARD SELF-DIAGNOSIS OPERATION PROCEDURE
1. Turn ignition switch OFF.
2. Start engine.
3. From 5 seconds through 15 seconds after start engine, press
RESUME/ACCELERATE switch 5 times, and SET/COAST
switch 5 times.
NOTE:
• Never turn the MAIN switch ON.
• When operation above is not completed from 5 seconds
through 15 seconds, start again from above go to 1.
4. When the on board self-diagnosis starts up, the ICC system display shows DTC No. (1) at the set vehicle speed indicator.
NOTE:
• DTC will disappear after 5 minutes.
• When more than one malfunction is detected, a maximum of 3 code numbers can be stored; the latest
malfunction will be displayed first.

ERASING ON BOARD SELF-DIAGNOSIS
1. Stop the vehicle and turn ignition switch OFF.
2. Start engine and start on board self-diagnosis.
3. During on board self-diagnosis, press CANCEL switch 5 times,
and DISTANCE switch 5 times in this order.
NOTE:
• Press them within 10 seconds after pressing CANCEL switch
at first.
• When operation is not completed within 10 seconds, start
again from step 2 above.
4. DTC 55 will be shown.
NOTE:
DTC of an existing malfunction will not be erased.
5. Turn ignition switch OFF to exit the diagnosis.

 

Googling around I found some threads on other forums of others talking about this issue on their Titan's and M's. No resolution posted though.

 

My G35S 6 MT also surges going downhill on cruise control, and I agree, it's very annoying. Sometimes it's so bad it almost feels like the brakes were momentarily applied. Like other posters, I've never had any other car do this on cruise control.

I have a suspicion the problem may not be the cruise control itself, but is actually caused by the cruise control attempting to react to the hesitations and stumbles that often occur when applying light throttle or immediately after closing the throttle (see numerous posts about stumbles and hesitations when accelerating, another annoyance that shouldn't be there). I think if the light throttle hesitation/stumble problem were fixed, the cruise would work much better.

I will bring this up with the dealer when my car is in for the 3750 service.

 

I just found that a FIX has been made via your dealer on this problem. Dealerships have gotten a new computer/laptop & software to fix a variety of issues within the electronic controls. Finally this will be fixed! If you want a copy of the bulletin, email me... mrjacksprat@comcast.net

 

yeah i have this problem too, I assumed all cruise controls were like this; this is the first one i've used extensively.

it happens both on rolling hills and more steep ones, more pronounced on the latter.

 

The bulletin has also been posted in the FAQ thread that is stickied.

 

Has anybody had this TSB done?

I was talking to the dealer to get an appontment for the intelligent key replacement and I asked about this cruise control fix. He said it didn't apply to Canadian vehicles??

 

I read the TSB and it doesn't apply to cars with ICC, I have the ICC as well as the OP and we have the same issue with surging on certain grades of hills.

What I find as a temp fix is to go faster then the cruise speed by hitting the accelerator and it won't try and slow you down.. it will wait until you get back to your set speed, and then kick on again.