GM Service Manual Online
For 1990-2009 cars only

The RTD scan tool data list contains all the real time damping system related parameters that are available on the scan tool. The parameters in the list are arranged in alphabetical order. The column, Data List, indicates the location of the parameter within the scan tool menu selections.

There are two RPO codes that are incorporated into the data list. The two RPO codes are Z55 and ZK3. The earlier version of the ESC module has RPO Z55 and ZK3. The later version of the ESC module has RPOs Z55 only. The data list is composed of parameters for both RPOs. One of the two Vehicle Speed parameters displayed is designated as ZK3 only.

Use the RTD scan tool data list as directed by a diagnostic table or in order to supplement the diagnostic procedures. Begin all of the diagnostic procedures with the RTD Diagnostic System Check. Use the RTD scan tool data list only after the following is determined:

    • The RTD Diagnostic System Check is complete
    • The on board diagnostics are operating correctly
    • No diagnostic trouble codes (DTCs) are displayed

The typical scan tool data values are an average of the displayed values recorded from normally operating vehicles. The typical scan tool data values are intended to represent what a normally functioning system would display with certain preliminary settings. The values you get may vary slightly due to a low battery charge or other reasons. But the values should be very close.

Use only the parameters listed in the tables for diagnosis. If a scan tool reads other parameters, the values are not recommended for use in diagnosis. Refer to Scan Tool Data Definitions for further detailed information.

Data Display

The scan tool's input display function can be helpful in determining if the electronic suspension control (ESC) module is receiving the correct input status. This can assist in determining if the RTD system is actually commanding a suspension damper solenoid.

Cycle Outputs

A scan tool may be used in order to command the suspension damper solenoids and SERVICE RIDE CONTROL message ON or OFF. This can be very helpful in determining if a certain portion of a circuit or a component is in working order. The following tests are available under the Special Functions selection. The following can be commanded ON or OFF:

    • Suspension damper solenoids
    • SERVICE RIDE CONTROL message

RTD Scan Tool Data List

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Park brake set with the ignition switch ON / Ignition Switch in RUN / Engine running / Automatic Transmission in PARK / Air Conditioning is OFF

Compressor Signal (If Equipped)

Data

ON/OFF

OFF

Controller Battery Voltage

Data

Volts

12.0 - 14.7 Volts -varies with the vehicle

EVO Actual Current (If Equipped)

Data

ma

0

EVO Desired Current (If Equipped)

Data

ma

0

EVO Drive PWM (If Equipped)

Data

Percent

100

Exhaust Signal (If Equipped)

Data

ON/OFF

OFF

Left Front Damper Actuator

Data

ON/OFF

OFF

Left Front Position Sensor

Data

Volts

0.5 to 4.5

Left Rear Damper Actuator

Data

ON/OFF

OFF

Left Rear Position Sensor

Data

Volts

0.5 to 4.5

Lift/Dive Status

Data

Active/Inactive

Inactive

Rear Leveling Air Pressure (If Equipped)

Data

PSI

-16.0 to 187.8

Rear Leveling Air Pressure (If Equipped)

Data

Volts

0.15 to 4.85

Right Front Damper Actuator

Data

ON/OFF

OFF

Right Front Position Sensor

Data

Volts

0.5 to 4.5

Right Rear Damper Actuator

Data

ON/OFF

OFF

Right Rear Position Sensor

Data

Volts

0.5 to 4.5

Sensor Supply Voltage

Data

Volts

4.85

Steering Wheel Position Signal 1

Data

Volts

4.0

Steering Wheel Position Signal 2

Data

Volts

2.0

Steering Wheel Rate

Data

RPM

0

Vehicle Speed

Data

MPH

0

Vehicle Speed (ZK3 only)

Data

MPH

0