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Discussion Starter #1 (Edited)
Gen 1s did not have start-stop so this info is best suited for the gen2 forum instead of general info. Detailed info on GM's Start-Stop systems introduced in 2014. The 2018 Traverse uses the DC to DC system with a power supply transformer

Enabling Criteria

The following vehicle conditions must be met for an Auto Stop event to take place.


  • Initial minimum vehicle speed during the drive cycle must reach 12 MPH (19 km/h). Subsequent minimum speed may vary from 1-6 MPH (2-10 km/h), depending on the vehicle.
  • In a vehicle with a manual transmission, the transmission must be in Neutral and the clutch pedal fully released.
  • Ambient and engine coolant temperature correlation must meet specified values.
  • Ambient and transmission fluid temperature correlation must meet specified values.
  • Hood switch status is closed.
  • Brake pedal is depressed beyond a specific value (approximately 27%).
  • Accelerator pedal is in the learned home position.
  • Brake booster vacuum is greater than 45 kPa (7 PSI).
  • Transmission gear selector is in the Drive position.
  • Vehicle speed is less than 3 MPH (5 km/h).
  • Engine speed is below 1500 RPM.
  • Engine coolant temperature is less than 248°F (120°C).
  • No A/C compressor request from the HVAC system (A/C or Defrost modes).
  • Battery voltage greater than 12 V.
  • Battery state of charge in the ECM is greater than 75% (changes with state of health).
The following conditions will enable an engine restart.


  • Transmission gear selector is moved from the Drive position.
  • In a vehicle with a manual transmission, the driver depresses the clutch pedal.
  • Driver removes pressure from the brake or depresses the accelerator pedal while the vehicle is in the Drive.
  • Brake booster vacuum is less than 40 kPa (6 PSI).
  • A/C compressor request from HVAC (A/C or Defrost modes).
  • Battery voltage less than 11 V.
  • Battery state of charge is less than 73% (changes with state of health).
  • Hood switch status changes to open.
  • Auto Stop time exceeds 2 minutes.
Info is located at

http://sandyblogs.com/techlink/?p=8495
 
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with this many permissives,

ought to be several undetectable, reversible, quick to do, permanent, disables for the start stop feature. Hood switch would be my choice.

on the Fords with towing packages, its easy to fake a trailer being towed which disables it (add a light bulb or load resistor to the trailer light wiring).
 

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Discussion Starter #3
with this many permissives,

ought to be several undetectable, reversible, quick to do, permanent, disables for the start stop feature........................
Tried both

Hood switch would be my choice.

No go - defeats the remote start capability - plus annoying message and/or graphic in the DIC

on the Fords with towing packages, its easy to fake a trailer being towed which disables it

No go - Installed a 9 pin connector with LED test lights as a load and s/s still operational
 

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Discussion Starter #5
I thought you liked this stop-start ?

It is a deal killer for me.
Was almost a deal killer for me because my new design '16 Malibu had the system while the competing, discontinued, cheaper old '16 Malibu did not. Didn't like it but positives outweighed the negatives so bit the bullet and bought the Malibu which uses the previous 2 battery s/s system. Initially I wasn't too crazy about the 2 battery system in my '16 Malibu......didn't much care since it is basically a grocery getter and there is only one stop light between us and the stores.......plus use as a loaner when the kids come in from the West Coast. Played with it and no easy way to defeat unless you drive with the tranny in L9.

The different DC-DC inverter system in the Traverse includes refinements in the starting system and software operating the system when it enters auto stop. Quieter and smoother than competing systems. Once again the numerous positives for the '18 Traverse vs. my '15 Traverse trade w/o the system outweighed its start/stop. Startup faster than the foot can be moved from the brake to the accelerator and so unobtrusive, I came to live with it and now like it; not love it.
 

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Discussion Starter #8
with this many permissives,

ought to be several undetectable, reversible, quick to do, permanent, disables for the start stop feature. Hood switch would be my choice.

on the Fords with towing packages, its easy to fake a trailer being towed which disables it (add a light bulb or load resistor to the trailer light wiring).
In looking at what can be determined by eye absent a detailed electrical and mechanical schematic of the system, it appears that the best method to defeat the auto stop might be to fool the system into thinking the vacuum in the brake booster is under 7 psi. In place of the typical check valve located on the vacuum booster diaphragm the '18 has a similar fitting, but it contains a three wire electrical connector which could be from a pressure sensor used to measure the psi in the reservoir. Also the vacuum hose going to the engine vacuum source has an additional in line plastic fitting which looks like a "second?" check valve. If the pressure sensor like most others operates by the ECU measuring resistance readings from the sensor, it should be possible by either adding a resistor (in line with the sensor to increase resistance or in parallel to reduce the resistance) to fool the ECU into keep the engine running to supply vacuum. That is, as with the hood switch, provided the engineers haven't designed a low vacuum warning within the DIC or to trigger a lit engine light into the system.
 

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This is my first vehicle with stop/start feature. It really annoyed me at first, but after 3 months of driving my new Traverse, I have adapted my driving a little bit and don't mind it as much anymore.

Here are a few things that I do that make the Start/Stop feature a little easier to live with:

- When I'm sitting at a light, I look at the other traffic lights and anticipate when my light will turn green. I just lift my foot of the brake slightly to restart the engine prior to the green light.

- If I'm coming to a Stop Sign, I will slow down a little further ahead than I usually did prior to the stop and minimize my brake pressure at the stop; most times the engine will not turn and I'm ready to go again.

- There is a steep hill with a traffic light at the top on my way home. When traffic is stopped on the hill due to the red light, I just let my vehicle coast to a stop by itself without applying the brake. This keeps the engine running.

- If you are stopped at a traffic light with the engine off and you want to keep have your engine on while you wait, just briefly release the pressure off the brake pedal to restart the engine and reapply enough brake pressure to keep the vehicle in place until you are ready to go.

When there is something new that I can't change, I usually try to adapt.
 

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^^^
x2 on that

I wasn't thrilled to learn that it had it and that you can't shut it off, but if you change your driving style you can minimize it impacting your driving.
Slowing down early/watching the lights to keep the engine running or getting it started earlier.
But when at a light for a while, it does make sense to shut off and save fuel...even if minimal
 

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Thomcat,

Quoted:
"The following vehicle conditions must be met for an Auto Stop event to take place.
...No A/C compressor request from the HVAC system (A/C or Defrost modes)."

Does that mean the "start/stop" won't engage when the compressor is running?

I'm not sure, but doesn't the compressor constantly run when the AC is on?
 

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Discussion Starter #12
Thomcat,

Quoted:
"The following vehicle conditions must be met for an Auto Stop event to take place.
...No A/C compressor request from the HVAC system (A/C or Defrost modes)."

Does that mean the "start/stop" won't engage when the compressor is running?

I'm not sure, but doesn't the compressor constantly run when the AC is on?
No and No.

Start stop will engage even if compressor is running and will stop the engine and compressor but the HVAC fan will continue to run off the battery to scavenge remaining cool air from the evaporator - if the interior temperature is within a degree or two of the limit set on the dial - it will not engage and the compressor will continue to run (or the engine will restart if already in a stop cycle) once the interior temperature is set or rises a degree or two above the set temperature and the system calls from more cooling. Want to prevent an auto stop? - continue to lower the temp dial to call for more cooling and the engine will continue to run or restart from a stop cycle.

Yellow light in A/C button means only that power is active to the compressor circuit not necessarily that the compressor is running. The compressor has an electric clutch that engages whenever the interior temps is set and the system calls for cooling or if max defrost/defog is engaged to provide low humidity air. The clutch will disengage and the compressor will stop rotating once the interior temperature requirements are met, the compressor loses refrigerant and the low pressure cutout kicks in or the outside temperatures becomes so cold it will freeze the compressor lines at which point you need heat not AC anyway. But the light remains on regardless of the clutch status, whether the compressor is turning or stopped.
 

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Workaround

I found that if shifter is put in L, and using thie button top of shifter cycle to 9, stop-start will be dsabled until shifter is returned to D.
Until it is changed, it will shift normaly ,just like it was not there.
 

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As long that the cop is not watching you if you did not make a complete stop at the stop sign and is smilling at you with a ticket. Lol
 

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The auto stop has never shut the engine off with my 2018 Traverse when the AC is operating. The rest of the time it has no impact on my driving. Even when at a stop and making a left turn when the signal changes there is zero delay as compared to a car without this capability. To me it is a lot of whining about something that is trivial.



Cars also change as engineers on occasion will refine an engine or other component over time. Lots of diesel emissions problems with the 2011-2012 GM trucks were corrected over the years. There may have been problems with the 9-speed transmission but I have not experienced any nor seen any posts regarding this transmission on the GM truck forums. On the other hand I test drove a 2018 Honda Pilot with its 9-speed transmission and it took 3-4 seconds to downshift after flooring the accelerator and merging into freeway traffic was very dangerous.
 

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Thanks for this awesome info. I nerded out reading through it and the links about the auto stop/start features last night. One of my biggest concerns about buying the 2018 LS I have was how well this system worked, how intrusive it was, and the longer term wear and tear effects on the vehicle. All this info has put me alot more at ease on the subject I found it really interesting to read about.
 

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Gen 1s did not have start-stop so this info is best suited for the gen2 forum instead of general info. Detailed info on GM's Start-Stop systems introduced in 2014. The 2018 Traverse uses the DC to DC system with a power supply transformer

Enabling Criteria

The following vehicle conditions must be met for an Auto Stop event to take place.


  • Initial minimum vehicle speed during the drive cycle must reach 12 MPH (19 km/h). Subsequent minimum speed may vary from 1-6 MPH (2-10 km/h), depending on the vehicle.
  • In a vehicle with a manual transmission, the transmission must be in Neutral and the clutch pedal fully released.
  • Ambient and engine coolant temperature correlation must meet specified values.
  • Ambient and transmission fluid temperature correlation must meet specified values.
  • Hood switch status is closed.
  • Brake pedal is depressed beyond a specific value (approximately 27%).
  • Accelerator pedal is in the learned home position.
  • Brake booster vacuum is greater than 45 kPa (7 PSI).
  • Transmission gear selector is in the Drive position.
  • Vehicle speed is less than 3 MPH (5 km/h).
  • Engine speed is below 1500 RPM.
  • Engine coolant temperature is less than 248°F (120°C).
  • No A/C compressor request from the HVAC system (A/C or Defrost modes).
  • Battery voltage greater than 12 V.
  • Battery state of charge in the ECM is greater than 75% (changes with state of health).
The following conditions will enable an engine restart.


  • Transmission gear selector is moved from the Drive position.
  • In a vehicle with a manual transmission, the driver depresses the clutch pedal.
  • Driver removes pressure from the brake or depresses the accelerator pedal while the vehicle is in the Drive.
  • Brake booster vacuum is less than 40 kPa (6 PSI).
  • A/C compressor request from HVAC (A/C or Defrost modes).
  • Battery voltage less than 11 V.
  • Battery state of charge is less than 73% (changes with state of health).
  • Hood switch status changes to open.
  • Auto Stop time exceeds 2 minutes.
Info is located at

http://sandyblogs.com/techlink/?p=8495

Start/stop needs to be disabled for me to buy this car. I cannot and will not drive with this dumb feature being forced on me.:mad:
 
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