GM Service Manual Online
For 1990-2009 cars only
Table 1: Engine Control Module (ECM)
Table 2: Instrument Panel Cluster (IPC)
Table 3: HUD

The scan tool data lists contain all the instrument panel, gage, and console related parameters that are available on the scan tool. The parameters in the list are arranged in alphabetical order. The data list column indicates the location of the parameter within the scan tool menu selections.

Use the scan tool data lists as directed by a diagnostic table or in order to supplement the diagnostic procedures. Begin all of the diagnostic procedures with Diagnostic System Check - Vehicle .

Use the scan tool data lists only after the following is determined:

    • There is no published DTC procedure nor published symptom procedure for the customer concern.
    • The DTC or symptom procedure indicated by the diagnostic system check does not resolve the customer concern.

The typical data values are obtained from a properly operating vehicle under the conditions specified in the first row of the scan tool data list table. Comparison of the parameter values from the suspect vehicle with the typical data values may reveal the source of the customer concern.

Engine Control Module (ECM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Engine Idling/Normal Operating Temperature

Change Engine Oil Indicator Command

IPC ECM Data

On/Off

Off

Cruise Control Active

IPC ECM Data

Inactive/Active/Invalid

Inactive

ECT

IPC ECM Data

Celsius (Fahrenheit)

85-105°C (185-220°F)

Engine Oil Level Switch

IPC ECM Data

OK/Low

OK

Engine Oil Pressure Sensor

IPC ECM Data

kPa (psi)

Varies w/Oil Pressure

Engine Oil Temperature Calculated

IPC ECM Data

Celsius (Fahrenheit)

Varies w/Oil Temperature

Engine Speed

IPC ECM Data

RPM

±100 RPM from Desired Idle Speed

Engine Speed Circuit Status

IPC ECM Data

SHORT GND/OPEN/ INCOMPLETE/SHORT B+/OK

OK

Fuel Level Sensor - Left Tank

IPC ECM Data

Volts

Varies w/Fuel Level

Fuel Level Sensor - Right Tank

IPC ECM Data

Volts

Varies w/Fuel Level

Fuel Tank Level Remaining

IPC ECM Data

Liters (Gallons)

Varies w/Fuel Level

Ignition Accessory Signal

IPC ECM Data

On/Off

On

Ignition 1 Signal

IPC ECM Data

Volts

9-18 V

Low Engine Oil Level Indicator Command

IPC ECM Data

On/Off

Off

Low EOP Indicator Command

IPC ECM Data

On/Off

Off

MIL Circuit Status

IPC ECM Data

SHORT GND/OPEN/ INCOMPLETE/SHORT B+/OK

OK

MIL Command

IPC ECM Data

On/Off

Off

Non-Driven Wheel Speed

IPC ECM Data

Km/h (mph)

Varies

Odometer

IPC ECM Data

km/miles

Varies

Skip Shift Lamp Command (If Equipped)

IPC ECM Data

On/Off

Off

Vehicle Speed Circuit Status

IPC ECM Data

OK/SHORT GND/ SHORT B+/ INCOMPLETE

--

Vehicle Speed Sensor

IPC ECM Data

kilometers per hour (miles per hour)

0 km/h (0 mph)

Instrument Panel Cluster (IPC)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON/Engine OFF/Park Brake Unapplied

1-4 Shift Lamp

IPC Input/Output

Off/On

Off

ABS Telltale

IPC Input/Output

Off/On

Off

Air Bag Indicator Command

IPC Input/Output

Off/On

Off

Average Fuel Economy

IPC Data 2

Liters (Gallons)

Varies

Average Speed

IPC Data 1

Km/h (mph)

Km/h (mph)

Battery Voltage Signal

IPC Data 1

Volts

9-18 Volts

Brake Fluid Level Switch

IPC Input/Output

Off/On

Off

Brake Warning Indicator Command

IPC Input/Output

Off/On

Off

Dim Down Switch

IPC Input/Output

Inactive/Active

Inactive

Dim Up Switch

IPC Input/Output

Inactive/Active

Inactive

Dome Lamp Switch

IPC Input/Output

Off/On

Off

ECT

IPC Data 1

°C (°F)

Varies

Engine Oil Life

IPC Data 1

0-100%

Varies wOil Life

Engine Oil Pressure

IPC Data 1

kPa (psi)

Varies w/Oil Pressure

Engine Speed Signal

IPC Data 1

RPM

±100 RPM from Desired Idle Speed

Front Fog Indicator Command

IPC Input/Output

Off/On

Off

Fuel Gauge Select Sw.

IPC Input/Output

Released/Depressed

Released

Fuel Level

IPC Data 1

0-100%

Varies w/Fuel Level

Fuel Range

IPC Data 2

Kilometers (Miles)

Varies

Gauge Switch

IPC Input/Output

Inactive/Active

Inactive

Headlamps On Indicator

IPC Input/Output

Off/On

Off

High Beam Indicator Command

IPC Input/Output

Off/On

Off

Inst. Fuel Economy

IPC Data 2

Liters (Gallons)

Varies

Left Turn Signal

IPC Input/Output

Off/On

Off

LF Tire Pressure

IPC Data 1

kPa (psi)

Varies w/Tire Pressure

Low Tire Press. Lamp

IPC Input/Output

Off/On

Off

Low Traction Lamp Command

IPC Input/Output

Off/On

Off

LR Tire Pressure

IPC Data 1

kPa (psi)

Varies w/Tire Pressure

Options Switch

IPC Input/Output

Inactive/Active

Inactive

Odometer

IPC Data 2

Kilometers (Miles)

Varies (0-99,999)

Park Brake Switch

IPC Input/Output

Released/Applied

Released

Park Lamps Signal

IPC Input/Output

Off/On

Off

Rear Fog Indicator Command

IPC Input/Output

Off/On

Off

Reset Switch

IPC Input/Output

Inactive/Active

Inactive

RF Tire Pressure

IPC Data 1

kPa (psi)

Varies w/Tire Pressure

Right Turn Signal

IPC Input/Output

Off/On

Off

RR Tire Pressure

IPC Data 1

kPa (psi)

Varies w/Tire Pressure

Seat Belt Indicator Command

IPC Input/Output

Off/On

Off

Security Indicator Command

IPC Input/Output

Off/On

Off

Trip Odometer A/B Switch

IPC Input/Output

Off/On

Off

Trip Odometer A

IPC Data 2

Kilometer/Miles

Varies

Trip Odometer B

IPC Data 2

Miles

Varies

Trip Odometer A

IPC Data 2

Kilometers

Varies

Trip Odometer B

IPC Data 2

Kilometers

Varies

Vehicle Speed Signal

IPC Data 1

kilometers per hour (miles per hour)

0 km/h (0 mph)

Windshield Washer Fluid Switch

IPC Input/Output

Low Fluid/OK

OK

HUD

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON/Engine OFF/Park Brake Unapplied

Adjust Display Down Switch

IPC HUD Data

Inactive/Active

Inactive

Adjust Display Up Switch

IPC HUD Data

Inactive/Active

Inactive

Battery Voltage Signal

IPC HUD Data

Volts

9-16 V

English Metric Status

IPC HUD Data

English/Metric

English

Language

IPC HUD Data

English, French, German, Italian, Spanish, or Japanese

Varies w/Selection

Navigation Present

IPC HUD Data

Not Present/Present

Not Present

Page Switch

IPC HUD Data

Inactive/Active

Inactive