The owner of an Escalade, Silverado, Tahoe, Sierra, or Yukon equipped with the Two-Mode Hybrid option may comment that the Auto Stop function does not operate at all in hot or cold temperatures or takes a long time to activate in cold ambient temperatures. Customers may also comment that fuel economy is less than expected. This concern may be considered a normal condition with certain conditions and driving maneuvers.
Inform the customer that ambient conditions and driving habits have a direct correlation with fuel economy. The Auto Stop mode may not be enabled if certain hybrid and vehicle components are too hot or too cold.
In warm temperatures, the hybrid batteries, the hybrid cooling system and the engine must all be kept cool for Auto Stop mode. Running the interior air conditioning and keeping the hybrid battery vents unrestricted will help keep the hybrid batteries cool.
In cold temperatures, the hybrid battery module temperature, engine coolant temperature, transmission fluid temperature, and cabin temperature must be warmed up before Auto Stop is allowed. The hybrid controllers also monitor ambient temperatures and interior temperature along with the above mentioned criteria to determine desired Auto Stop conditions.
The Auto Stop criteria are highly dependent on the outside air ambient temperature. Depending upon the overnight soak time, specific drive cycles, and the factors listed above, it may take an hour before the first Auto Stop occurs.
Observed fuel economy is affected by heavy acceleration, which requires more engine operation and, thus, more fuel consumption. Also, heavy braking does not allow regenerative braking to occur.
Fuel economy will be the same as a base truck under heavy throttle and brake apply. Adjusting both braking and acceleration driving habits will result in the higher system efficiency. Refer the customer to monitor Active Fuel Management (AFM) information on the hybrid navigation/radio display screen or the efficiency gauge to learn driving habits and conditions that improve fuel economy. This includes trying to keep the efficiency gauge in the green zone as much as possible and trying to drive in 4-cylinder mode as long as possible. The transmission gear shift selector should be placed in Drive and not in Manual for best fuel economy. Auto Stop is inhibited in the Manual transmission shift ranges.
Additional tips to improve fuel economy include keeping tires properly inflated, accelerating to allow for as much Mode 1 electric propulsion as possible, limiting the use of remote start, reasonable highway speeds, minimizing unnecessary cargo or mass, and keeping the transfer case in 2WD instead of Auto.
If there are no DTCs found in the vehicle control modules that would prohibit Auto Stop and the hood switch reads correctly, this condition should be considered an operating characteristic. Monitor the HPCM (Hybrid Powertrain Control Module) and Auto Stop Inhibit Reason data list to identify the normal inhibit reason.
- Thanks to Chuck Krepp
Inform the customer that ambient conditions and driving habits have a direct correlation with fuel economy. The Auto Stop mode may not be enabled if certain hybrid and vehicle components are too hot or too cold.
In warm temperatures, the hybrid batteries, the hybrid cooling system and the engine must all be kept cool for Auto Stop mode. Running the interior air conditioning and keeping the hybrid battery vents unrestricted will help keep the hybrid batteries cool.
In cold temperatures, the hybrid battery module temperature, engine coolant temperature, transmission fluid temperature, and cabin temperature must be warmed up before Auto Stop is allowed. The hybrid controllers also monitor ambient temperatures and interior temperature along with the above mentioned criteria to determine desired Auto Stop conditions.
The Auto Stop criteria are highly dependent on the outside air ambient temperature. Depending upon the overnight soak time, specific drive cycles, and the factors listed above, it may take an hour before the first Auto Stop occurs.
Observed fuel economy is affected by heavy acceleration, which requires more engine operation and, thus, more fuel consumption. Also, heavy braking does not allow regenerative braking to occur.
Fuel economy will be the same as a base truck under heavy throttle and brake apply. Adjusting both braking and acceleration driving habits will result in the higher system efficiency. Refer the customer to monitor Active Fuel Management (AFM) information on the hybrid navigation/radio display screen or the efficiency gauge to learn driving habits and conditions that improve fuel economy. This includes trying to keep the efficiency gauge in the green zone as much as possible and trying to drive in 4-cylinder mode as long as possible. The transmission gear shift selector should be placed in Drive and not in Manual for best fuel economy. Auto Stop is inhibited in the Manual transmission shift ranges.
Additional tips to improve fuel economy include keeping tires properly inflated, accelerating to allow for as much Mode 1 electric propulsion as possible, limiting the use of remote start, reasonable highway speeds, minimizing unnecessary cargo or mass, and keeping the transfer case in 2WD instead of Auto.
If there are no DTCs found in the vehicle control modules that would prohibit Auto Stop and the hood switch reads correctly, this condition should be considered an operating characteristic. Monitor the HPCM (Hybrid Powertrain Control Module) and Auto Stop Inhibit Reason data list to identify the normal inhibit reason.
- Thanks to Chuck Krepp
Leave a comment