Features

Silverado/Sierra Hybrid Truck Features









The Chevrolet Silverado and GMC Sierra Hybrid trucks utilize a standard production V8 gasoline engine for 2004, but they incorporate several new sub-systems:

1. Electro-hydraulic power assist.
2. Automatic engine stop-start:
- Improved fuel economy
- 42-volt battery pack
3. 2.4 kilowatt portable generator.
4. 120-volt A/C (VAC) electrical outlets.

1. Electro-hydraulic Power Steering (EHPS) and Brake Assist



The standard power steering pump has been replaced by a 42-volt electro-hydraulic power steering pump that generates hydraulic pressure for steering and brake assist.




The hydraulic system utilizes a mineral-based oil manufactured by Pentosin, which has been used in other vehicles for a number of years.







2. Automatic Engine Start/Stop
This feature improves fuel economy and reduces vehicle carbon dioxide emissions by shutting the engine off:

- During coasting, when the vehicle is traveling below 15 mph.

- During breaking.

- While in drive with the vehicle stopped.

- While in Park.




3. Starter/Generator (SG)
- Electric machine that functions as a starter and a generator

- Generates electricity

- Located inside transmission bell housing at the rear of the engine (the standard starter motor and generator have been removed).




4. 120 VAC Auxiliary Power Outlet (APO) Button
The main control of the 120-volt system is located to the right of the heating, vent and air conditioner controls in the center of the instrument panel.




- Press button to turn auxiliary power outlets ON; press it again to turn them OFF.

- Indicator light illuminates when 120 VAC APO system is activated.










120 VAC Auxiliary Power Outlet (APO) Operation
Two modes of operation:

- Normal operation: Generates 120-volts A/C while the vehicle is being driven down the road

- Continuous mode: generates 120-volts A/C while the vehicle is parked with the ignition locked. Ignition key can be removed from the vehicle.

Starter/Generator Control Module (SGCM) and Cooling System



- Contains an independent cooling system.

- Uses Dex-Cool coolant, the same as that used in the engine and mixed in the same ratio (50/50).

Independent Cooling system for the SGCM



- Use the same safety procedures as when working with engine coolant.

- Use caution if disconnecting or cutting hoses, as the system may:
- Be under pressure (approximately 5 psi).
- Coolant may be hot.




CAUTION:
To avoid being burned, do not remove the starter/generator control module (SGCM) cap while the SGCM is hot. The cooling system will release scalding fluid and stream under pressure if the SGCM cap is removed while the SGCM is still hot.

Starter/Generator Control Module (SGCM) Electrical System Connections






- Located on the passenger side of the engine compartment.

- Inverts 42-volt electrical power to 120-volts A/C.

- Not the location of the 12-volt circuit, circuit wires are contained within a protective orange covering.







- Three phase cables from the starter/generator carry up to 50-volts A/C.

CAUTION:
To reduce risk of severe shock and burns, always treat the 3-phase cable and connectors as if the voltage is present.

120-Volt Alternating Current (VAC) Outlet Locations



- Near the floor under the center of the rear passenger seat.

- At the rear of the pickup box on the passenger side.

Energy Storage Box (ESB)






- Located under the rear passenger seat.

- A manually operated battery disconnect switch is located on the passenger side of the ESB behind an access panel.







- A trim cover is secured with push-pin rivets.

- Contains 42-volt battery pack (three 12-volt starved electrolyte AGM batteries wired in series).
- AGM technology utilizes a minimal amount of electrolyte. Should the integrity of a battery case be compromised, the amount of electrolyte that will exit the case is very small.

- The 42-volt batteries are enclosed in a metal box whose lid is secured with Trox bit bolts.

- Contains the energy storage control module (ESCM):
- Monitors the battery's state of charge.
- Alerts the driver on the instrument panel, if necessary.

- The physical characteristics of the ESB have been engineered to meet crash worthiness test and standards.