GM Service Manual Online
For 1990-2009 cars only
Adjust Display Down Switch: The scan tool displays Inactive/Active. This is the state of the HUD Display Down Switch. Active is displayed when switch is selected.

Adjust Display Up Switch: The scan tool displays Inactive/Active. This is the state of the HUD Display Up Switch. The scan tool displays Inactive/Active.

Battery Voltage: The scan tool displays 0-19 volts. This is the voltage measured at the battery positive voltage circuit of the HUD.

Change Engine Oil Indicator Command: the scan tool displays Off/On. This is the state of the change engine oil indicator as commanded by the ECM.

Chime: The scan tool displays Off/On. This is the current state of the vehicle chime function as detected by the IPC.

Commanded Gear: The scan tool displays Shift, 1st, 2nd, 3rd, 4th, 5th, Invalid, Invalid, Reverse, Neutral or Park. The scan tool display the current transmission range as commanded by the ECM.

Cruise Control Active: The scan tool displays No/Yes. This is the state of the cruise control as determined by the ECM.

Dim Down Switch: The scan tool displays Inactive/Active. The scan tool displays the state of the Dimmer Down Switch as commanded by the IPC.

Dimming Level: The scan tool displays 0-100 percent (%). This is the current state of the HUD display dimming as controlled from the dimmer switch.

Dim Select Switch: The scan tool displays Inactive/Active. The scan tool displays the state of the Dimmer Select Switch as commanded by the IPC.

Dim Up Switch: The scan tool displays Inactive/Active. The scan tool displays the state of the Dimmer Up Switch as commanded by the IPC.

ECT Sensor: The scan tool displays -40-151°C (-40-304°F). The ECM monitors the voltage at the signal circuit of the engine coolant temperature sensor. The voltage is inversely proportional to the engine coolant temperature.

Engine Oil Level Switch: The scan tool displays Ok/Low.This is the state of the engine oil level switch as monitored by the ECM.

Engine Oil Life Remaining: The scan tool displays 0 - 100 percent (%). the scan tool displya the engine oil life remaining as calculated by the ECM.

Engine Oil Pressure Sensor: The scan tool displays kPa or psi. The scan tool displays the current engine oil pressure as calculated by the ECM.

Engine Oil Pressure Sensor: The scan tool displays 0-5 volts. The scan tool displays the voltage at the signal circuit of the engine oil pressure sensor as determined by the ECM.

Engine Oil Temperature Sensor: The scan tool displays Celsius or Fahrenheit. The scan tool displays the current engine oil temperature as monitored by the ECM.

Engine Oil Temperature Calculated: The scan tool displays Celsius or Fahrenheit. The scan tool displays the current engine oil temperature as calculated by the ECM.

Engine Speed: The scan tool displays 0-9999 RPM. Engine speed is computed by the ECM from the ignition reference input. It should remain close to desired idle under various engine loads with the engine idling.

Engine Speed: The scan tool displays 0-9999 RPM. Engine speed is computed by the IPC via a discrete input from the ECM.

Engine Speed Circuit Status: The scan tool displays Incomplete/Short to Gnd/Open/Short to B+/Ok. This is the state of the engine speed signal circuit as monitored by the ECM.

English Metric Status: The scan tool displays English or Metric. The scan tool displays vehicle information in English or Metric system as selected from the IPC.

Fuel Level Sensor - Left Tank: The scan tool displays 0 - 5 volts. The scan tool displays the voltage at the signal circuit of the left fuel level sensor as calculated by the ECM.

Fuel Level Sensor - Right Tank: The scan tool displays 0 - 5 volts. The scan tool displays the voltage at the signal circuit of the right fuel level sensor as calculated by the ECM.

Fuel Tank Level Remaining: The scan tool displays the approximate value of fuel remaining in the gas tank in liters or gallons. The ECM calculates the amount of fuel remaining in the tanks based on the signal circuits of the fuel level sensors.

Fuel Tank Level Remaining: The scan tool displays 0 - 100 percent. The ECM calculates the amount of fuel remaining in the tanks based on the signal circuits of the fuel level sensors.

Ignition 1 Signal: The scan tool displays Volts. The scan tool displays the ignition 1 input voltage to the ECM.

Ignition Accessory Signal: The scan tool displays Off/On. This is the ignition accessory voltage signal as monitored by the ECM.

Information Down Switch: The scan tool displays Inactive/Active. This is the state of the DIC information down switch as detected by the IPC.

Information Up Switch: The scan tool displays Inactive/Active. This is the state of the DIC information up switch as detected by the IPC.

Language: The scan tool displays English, French, German, Italian, Spanish or Japanese. This is the language selected for the HUD.

Low Engine Oil Level Indicator Command:: The scan tool displays Off/On. This is the state of the low engine oil level indicator as monitored by the ECM.

Low EOP Indicator Command:: The scan tool displays Off/On. This is the state of the low engine oil pressure indicator as monitored by the ECM.

MIL Circuit Status: The scan tool displays Fault. The scan tool will display Fault for the MIL circuit as commanded by the ECM.

MIL Command: The scan tool displays Off/On. This is the commanded state of the malfunction indicator lamp (MIL) by the ECM. The malfunction indicator lamp should be On when the scan tool indicates the MIL Command is On.

Options Switch: The scan tool displays Inactive/Active. This is the state of the DIC Option Switch as detected by the IPC.

Odometer: The scan tool displays kilometers or miles. This is the total accumulated miles of the vehicle as calculated by the ECM.

Page Switch: The scan tool displays Inactive/Active. This is the state of the HUD page switch detected by the IPC.

Reset Switch: The scan tool displays Inactive/Active. This is the state of the DIC reset switch as detected by the IPC.

Vehicle Speed Circuit Status: The scan tool displays Incomplete/Short to Gnd/Open/Short to B+/Ok. This is the state of the vehicle speed signal circuit as monitored by the ECM.

Vehicle Speed Sensor: The scan tool displays 0-255 km/h (0-155 mph). This is the vehicle speed as calculated from the ECM.

Vehicle Speed Signal: The scan tool displays 0-255 km/h (0-155 mph). The IPC calculates the vehicle speed signal via a discrete input from the ECM.