Info - Fullsize Utility Vehicles - Suburban, Avalanche, EXT, ESV, Denali, Tahoe, Yukon, Escalade - New Model Feature and Service Guide

This is a special bulletin to introduce the new Fullsize Utility vehicles. The purpose of this bulletin is to familiarize dealership service personnel with the vehicle's features, and describe the actions the Service Department will need to take to ensure they are able to fully service this exciting new model.

Vehicles will begin shipping to dealers:

The purpose of this section is to familiarize you with the technical aspects of the vehicle.

Powertrain:

The following Powertrain combinations are available:

Brakes:

The vehicle is equipped with the BOSCH® brake system. The following vehicle performance enhancement systems are provided:

The electronic brake control module (EBCM) requires a power-up self-test at the beginning of each ignition cycle to verify correct operation of components before the various control system can be enabled. The master cylinder pressure sensor performs a self-test by sending a series of specific voltage signals to the EBCM, each for a predetermined amount of time.This phase of the power-up self-test may be heard by the driver, depending on how soon the engine is cranked and started after turning ON the ignition.

The second phase of the power-up self-test begins when the vehicle is driven at a speed greater than 16 km/h (10 mph) and the EBCM has not detected any traction control module (TCS) vehicle stability enhancement system (VSES) related malfunctions so far. When the brake switch indicates that the brake is not applied and the master cylinder pressure is detected as being low, the EBCM proceeds with the test. The EBCM isolates all of the wheels by closing the 4 isolation valves. Because all of the wheels are isolated during the second phase of the test, the test must be aborted if the brake is applied while the test is being performed. Occasionally, the driver may detect this by experiencing a momentary hard pedal.

Chassis:

The fullsize 1500 series utilities feature a new front coil over shock suspension with rack & pinion steering. Also, the 1500 series utilities will introduce a high angle, constant velocity intermediate shaft universal joint. The fullsize 1500 series rear suspension is a five link live axle with coil springs, shock absorbers and stabilizer bar. The fullsize 2500 series utilities feature a front torsion bar suspension with recirculating ball steering. The fullsize truck 2500 series rear suspension features leaf springs and shock absorbers with live axle. All models have sealed front wheel bearings. These bearings are pre-adjusted and need no lubrication. The front and rear suspension consists of the following components:

1500 Series:

2500 Series:

Electrical Architecture:

The communication among control modules is performed through the GMLAN high speed serial data circuit and the GM LAN low speed serial data circuit. The modules that need real time communication are attached to the high speed GMLAN network. The Body Control Module (BCM) is the gateway between the networks. The purpose of the gateway is to translate serial data messages between the GMLAN high speed bus and GMLAN low speed bus. Power to many of the vehicle's circuits is controlled by the module that is designated as the power mode master (PMM). This vehicle's power mode master is the BCM.

SI Document ID # 1740394 Data Link References identifies which serial data link that a particular module uses for in-vehicle data transmission. SI Document ID # 1741195 Control Module References identifies which modules require programming and set-up as well as links to schematics and repair instructions.

Navigation System / Rearview Camera System (RPO UVC):

The navigation radio provides the following:

The GPS antenna is attached to the bottom of the rear shelf and can be accessed through the rear compartment.

Notice:  Do not apply after-market glass tinting to the vehicle's windows. Glass tinting will interfere with the system's ability to receive GPS signals and cause the system to malfunction.

The navigation system's voice recognition allows for hands-free operation of the navigation and audio system features. The voice recognition can be used when the ignition is in Accessory or ON, or when retained accessory power (RAP) is active. This feature only works if the map DVD is inserted (in the DVD slot) and the AGREE button has been pressed.

Rear Vision Camera (if equipped)

When the transmission is in reverse, the rear vision system helps the driver determine how close an object, within the field of view, is to the rear bumper. A video camera is located on the liftgate above the license plate, or just under the endgate handle. The rear camera image is displayed on the radio/nav screen. Once the driver shifts out of REVERSE (R), the navigation screen will go back to the last screen that had been displayed, when any portion of the screen is touched, or if the vehicle speed is greater than 11 km/h (7 mph). The radio can display the following rear vision error messages:

The rear vision camera system may not work properly or display a clear image in the following situations:

Power Liftgate (RPO E61):

A power open or close can only be initiated from the fully closed or open positions while the vehicle is in park and the liftgate glass is closed. The power liftgate can be switched to manual mode with the on/off switch in the overhead console and during manual operation the power latch will still operate.

The liftgate control module continuously monitors the power liftgate operation and calculates its location and direction of travel using two hall-effect sensors that are part of the gear motor assembly. The hall-effect sensors are three wire sensors and are supplied with a 5-volt power circuit, ground and signal circuits from the liftgate control module. The hall-effect sensor signal circuits are referenced from battery voltage within the liftgate control module and pulsed low by the hall-effect sensors.

The power liftgate system uses a secondary object detection method which consists of object sensors fixed to both sides of the liftgate near the seal area. The object sensors consist of an internal fixed resistor and normally open switch contacts which when closed will by-pass the resistor. The signal circuit is supplied 5-volts through a resistor and monitored within the liftgate control module, and during normal power liftgate operation the signal circuit should remain a fixed value. When an object presses one of the sensors the contacts close and the resistor is by-passed causing the signal circuit voltage at the module to go low.

Ultrasonic Rear Park Assist (RPO UD7):

The object detection system will notify the driver when backing up at speeds less than 8 km/h (5 mph). The object detection system can detect objects 76 mm (3 in) wide and at least 254 mm (10 in) tall. It cannot detect objects above the level of the roof. If the object detection system detects a malfunction, a diagnostic trouble code (DTC) will be stored and the object detection will send a message to the I/P to scroll the SERVICE PARK ASSIST message on the DIC. Then the chime will sound and the red indicator on the information telltale center will flash continuously, notifying the driver that a malfunction exists.

Power Folding and Tumble Rear Seat:

The power fold and tumble second row seats are operated from the power fold switches in the overhead console or the rear switches on the panels behind the rear doors. Voltage to the power fold switches is supplied through the park enable relay while in a de-energized state. The park enable relay is controlled by the BCM through a high side drive control circuit and will be energized whenever the ignition is in the accessory, run, or crank positions and the transmission is not in park. The folding seat motors are supplied battery voltage from the REAR SEAT 20A fuse and grounded at the B pillars.

SIR Roof Air Bags and Rollover Sensor

Seat belts are the primary means of occupant restraint. The vehicle is also equipped with a supplemental inflatable restraint (SIR) system. The side supplemental inflatable restraint (SIR) system consists of the following components:

The roof rail modules (front/rear) are located in the headliner along the roof rails. The roof rail modules contain a housing, inflatable air bag, initiating device, and a canister of gas generating material.

The vehicle rollover sensor is used to supplement the side Supplemental Inflatable Restraint system. The sensing and diagnostic module (SDM) uses the input from the vehicle rollover sensor to assist in determining the severity of a vehicle rollover or near rollover condition. If the SDM determines a deployment is warranted, the SDM will cause current to flow through the deployment loops deploying the inflatable restraint roof rail modules.

Heated Windshield Washer Fluid (RPO XA7):

The heated windshield washer fluid operation is controlled by a separate switch located on the lower I/P console. When the heated washer fluid switch is pressed, ground is momentarily applied through the switch contacts and the heated washer fluid switch signal circuit to the windshield washer solvent heater assembly. In response to this signal, the washer solvent heater assembly then applies battery voltage to its internal washer fluid heating elements and pulls the heated washer fluid indicator control circuit low. The washer fluid is then heated as it passes through the heater assembly to the windshield.

Heated Steering Wheel (if equipped)

When the switch is depressed, a signal is sent to the heat module to command the heated steering wheel to heat up until either the normal operating temperature reaches the limit of 32°C (89.6°F), or the customer turns it off via the heated steering wheel switch. The heated steering wheel will also cease to operate if the vehicle temperature is at or above 32°C (89.6°F). The heated steering wheel takes approximately 3-4 minutes to reach the normal operating temperature and will take longer to heat up if the vehicle temperature is below -21°C (-5.8°F).

Remote Start:

Important: Caution should be taken when using Remote Start if the fuel level is low. It could be possible to run the vehicle out of fuel using the remote vehicle start if the fuel level is low.

The remote vehicle start (RVS) allows the customer to start the vehicle from outside the vehicle. This feature can be operated from a distance of 60 meters (196 ft). Once activated, the remote vehicle start feature is allowed to run for 10 minutes. A remote vehicle start once activated, can be stopped by:

Charging System:

The electrical power management (EPM) system is designed to monitor and control the charging system and send diagnostic messages to alert the driver of possible problems with the battery and generator. The EPM system primarily utilizes existing on-board computer capability to maximize the effectiveness of the generator, to manage the load, improve battery state-of-charge and life, and minimize the system's impact on fuel economy. The EPM system performs 3 functions:

In addition, the EPM function is designed to perform regulated voltage control (RVC) to improve battery SOC, battery life, and fuel economy. This is accomplished by using knowledge of the battery SOC and temperature to set the charging voltage to an optimum battery voltage level for recharging without detriment to battery life. The charging system voltage may vary from what you are used to and seem lower than normal in some circumstances. SI Document ID# 1674288 Charging System Description and Operation describes the operation in more detail.

Wiper Systems and Rainsense II (RPO CE1):

If equipped, the Rainsense II windshield wiper moisture sensor is located next to the inside rearview mirror and is mounted on the windshield. When active, the sensor is able to detect moisture on the windshield and automatically turn on the wipers. To activate the Rainsense feature, set the wipers to one of the five delay setting on the multifunction lever. Each of the five settings will adjust the sensitivity of the rain sensor. For more frequent wipes, select the higher setting. For fewer wipes select the lower setting (located closer to the OFF position).

Tire/Wheel Options:

Important:  The appropriate modules have been programmed for the wheel/tire size the vehicle was originally produced with. Changing wheel/tire sizes to something other than what that vehicle was produced with can cause speedometer inaccuracy and brake/suspension system concerns.

The following wheels are available by product:

Tahoe/Yukon:

Escalade:

All 2500 series vehicles are equipped with the standard 16" spare tire/wheel. All 1500 series vehicles are equipped with a 17" spare wheel/tire. The overall diameter of the spare wheel/tire assembly is close enough to the diameter of the 18", 20" and 22" road wheel/tire assembly. There are no restrictions for speed or mileage while using the 17" spare wheel/tire on a vehicle equipped with 18", 20" or 22" wheel/tires.

The purpose of this section is to familiarize you with some of the unique characteristics of the vehicle. The following functions may operate differently than what the customers are used to and are considered normal.

Heated Windshield Washer Fluid:

When the heated windshield washer fluid system is activated under certain outside temperature conditions, steam may flow out of the washer nozzles for a short period of time before washer fluid is sprayed. This is a normal condition. The first heated wash/wipe cycle may take up to 40 seconds to occur, depending on the outside temperature. After the first wash/wipe cycle, it may take up to 20 seconds for each of the remaining cycles.

Battery:

If the vehicle experiences a "dead" battery condition, it is important to clear codes in all modules. Failure to clear codes in the ECM may cause driveability concerns with the vehicle. Failure to clear codes in the other modules may lead to future mis-diagnosis.

The vehicle should be driven to relearn the tire pressures in the DIC. Failure to relearn the tire pressures will result in dashes being displayed on the DIC.

Adjustable Pedals: (if equipped)

If equipped, this feature provides the ability to change the throttle and brake pedal positions. The switch is located on the center console below the climate control system. No adjustments to the pedals can be made while the vehicle is in REVERSE (R) or while using the cruise control.

Retained Accessory Power (RAP):

Some customers may notice that the retained accessory power will only function for 3 minutes on vehicles with less than 23 km (15 mi). After the vehicle has accumulated more than 23 km (15 mi), the retained accessory power function will operate for 20 minutes.

Setting Time on Clock (Vehicles Equipped with RPOs UVB or U3U):

It is not possible to set the time if the vehicle does not have a GPS signal. The GPS system may not be available or interference may occur if the following happens:

The following items are serviced differently than on 2006 and prior fullsize utility vehicles.

Rollover Sensor:

The rollover sensor is located under the center console, mounted directly to the floor. Caution should be taken if servicing the rollover sensor. It is important that the ignition key is removed from the ignition and not in the ON position. If the key is ON, and the rollover sensor is turned over, at the least codes could be set in the sensor. The codes can not be cleared and the sensor will require replacement. In some cases, it would also be possible for one or more air bags to deploy.

Door Lock and Side Window Switch:

Door lock and side window switch have replaced the previous Passenger Door Module and Driver Door Module. It is not necessary to remove the door pads to service the door lock and side window switch.

Underhood Engine Wiring Harness Junction Block:

If more than 2 tabs are broken from the underhood engine wiring harness junction block, the component must be replaced. It is necessary to have 4 tabs to properly align the connector.

Overhead Console:

To service the Overhead Console, it is necessary to remove the two screws under the lens of the overhead lamp. The overhead console does not pop out like in the 2006 and prior models.

Trim Panels

Trim panels are retained by high retention clips and can no longer just be pulled off. The "chicklet" in the trim panel must be removed and then remove the screw to the high retention clip, leaving the clip in the metal as you remove the trim.

Radio / Amp:

The amp and subwoofer is located under the center console, along with the Rollover sensor.

The following new tools have been released for the 2007 Fullsize Utility vehicles:

*Dealers in Canada should refer to the latest training availability in the GM Canada Product Service Training Course Catalogue located on GM infoNET under Service & Body Training.

**Training availability will be released in conjunction with product availability.

The PDI was revised to ensure special attention is paid to the areas listed below. For dealers in Canada, the PDI form is available for download from the "GM World of Warranty" on the GMinfoNET.

Reset Fuel Economy:

Be sure to reset the fuel economy display to zero prior to delivery to the customer.

Tire Pressures:

Vehicles are shipped from the assembly plant with higher than recommended tire pressure. The pressures are optimized for transportation of the vehicle. Tire pressures are a key ingredient of ride quality. It is very important to adjust the tire pressures to the recommended level, as noted on the tire label located on the driver's door, prior to delivery.

Battery Life:

Check and charge the battery, if necessary. If is the dealer's responsibility to maintain the battery until delivery to the customer.

Brake Burnish:

If the vehicle has set for a long period of time, it will be necessary to burnish the brakes during the PDI test drive, prior to delivering the vehicle to the customer.