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For 1990-2009 cars only

Engine Control Module Scan Tool Information 2.0L Diesel

Table 1: Engine Control Module Scan Tool Data
Table 2: Engine Control Module (ECM) Scan Tool Output Controls

The Engine Control Module Scan Tool Data List contains all engine-related parameters that are available on the scan tool. This is a master list arranged in alphabetical order and not all the parameters listed are in every engine platform.

Use the Engine Scan Tool Data List only after the following is determined:

    • The Diagnostic System Check - Vehicle is completed.
    • No diagnostic trouble codes (DTCs)
    • On-board diagnostics are functioning properly

The scan tool values from a properly running engine may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents values that would be seen on a normally running engine.

Important: A scan tool that displays faulty data should not be used. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service manual for use in diagnosis.

Engine Control Module Scan Tool Data

Parameter

System State

Expected Value

Description

Base Operating Conditions: Engine Idling/Radiator Hose Hot/Park or Neutral/Closed Loop

5 Volt Reference 1, Reference 2, or Reference 3

Ignition ON

OK

This parameter displays the output voltage from the 5-volt reference circuit to the control module.

A/C Disengage Reason

A/C OFF

Invalid

This parameter displays the A/C compressor disengage reason. There are 8 different possible faults for the A/C compressor to disengage.

A/C High Side Pressure Sensor

A/C OFF

0-5 Volts

This parameter displays the voltage from the A/C high side pressure sensor signal circuit to the control module.

A/C ON

0-5 Volts

A/C High Side Pressure Sensor

A/C OFF

700-900 kPa (101-130 psi)

This parameter displays the pressure from the A/C high side pressure sensor signal circuit to the control module.

A/C ON

900-1300 kPa (130-174 psi)

A/C Compressor Clutch Relay Command

A/C ON

On

This parameter displays the state of the air conditioning (A/C) clutch relay control circuit as commanded by the control module.

A/C Request Signal

A/C ON

Yes

This parameter displays the state of the A/C request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls.

Accelerator Pedal Position Sensors

--

0%

This parameter displays the angle of accelerator pedal position as calculated by the control module using the signals from the APP sensors.

Alternator L Terminal

--

ON

This parameter displays whether the control module is allowing the generator to operate.

Ambient Air Temperature Calculated

--

Varies

This parameter displays the calculated ambient air temperature.

APP at Idle

--

Yes

This parameter displays the angle of the accelerator pedal position (APP) as calculated by the control module using the signals from the APP sensors.

APP Sensor 1 or 2

--

APP 1-1.02 Volts

APP 2-0.51 Volts

This parameter displays the voltage of each APP sensor signal circuit as measured by the control module.

APP Sensor 1 or 2 Position

--

APP 1-0%

APP 2-0%

This parameter displays the percent of each APP sensor signal circuit as measured by the control module.

Aux Htr. Relay 1 Command

--

OFF

This parameter displays the commanded state of the aux heater relay 1 control circuit.

Aux Htr. Relay 2 and 3 Command

--

OFF

This parameter displays the commanded state of the aux heater relay 2 and 3 control circuit.

Aux Heater Request

--

OFF

This parameter displays the requested state of the aux heater.

BARO

--

65-104 kPa (8-16 psi) - Varies with altitude

This parameter displays the barometric pressure. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.

BARO

--

0-5 Volts - Varies with altitude

This parameter displays the barometric pressure in voltage. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.

Battery Voltage

Ignition ON

B+

This parameter displays the voltage measured at the battery circuit of the control module.

Boost Pressure Sensor

--

82-110 kPa (12-16 psi)

This parameter displays the turbocharger boost pressure inside the engine as calculated by the control module based on the signal from the Boost pressure sensor.

Boost Pressure Sensor

--

1.45-1.75 Volts

This parameter displays the voltage of the turbocharger boost pressure inside the engine calculated by the control module based on the signal from the Boost pressure sensor.

Brake Lamps Brake Pedal Switch Signal

--

Released

This parameter displays the state of the brake pedal as determined by the stop lamp pedal switch.

Calculated Air Flow

--

630-690 g/s

This parameter displays the calculated air flow into the engine. The calculation is used in several diagnostics to determine when to run the diagnostics.

Calculated DPF Flow

--

24600-27000 Liters/Hours

The parameter displays the calculated flow of DPF.

Clutch Pedal Switch

--

Applied

This parameter displays the current state of the clutch pedal as determined by the control module. The control module monitors the pedal switch on the clutch pedal for vehicles equipped with a manual transmission.

Cruise Control

Cruise Control ON

Yes

This parameter displays the status of the cruise control system as determined by the control module.

Cruise Control Disengage 1-6 History

--

Reason

This parameter displays the history of the action taking with the cruise system.

Cruise Control ON/OFF Switch

Cruise Control ON

Yes

This parameter displays the state of the cruise ON/OFF switch input to the control module.

Cruise Control Release Brake Pedal Switch

--

Released

This parameter displays the state of the brake pedal as determined by the control module. The control module monitors the pedal switch on the brake pedal for vehicles equipped with an automatic transmission. The control module uses this information to release the torque convertor clutch when the brake pedal is applied.

Cruise Resume/Accelerator Switch

Cruise Resume/Accel. Switch ON

On

This parameter displays the state of the cruise Resume/Accel switch input to the control module from the cruise control system.

Cruise Control Set/Coast Switch

Cruise Set/Coast Switch ON

On

This parameter displays the state of the cruise Set/Coast switch input to the control module from the cruise control system.

Cooling Fan Control 1, Control 2, or Control 3 Command

Fans Commanded ON

On

This parameter displays the control module commanded state of the fan relay control circuits.

Cylinder Air

--

240.00-280.00 mg/stk

This parameter displays the actual amount of cylinder air.

Desired Boost Pressure

--

98 kPa

This parameter displays the desired turbocharger boost pressure inside the engine as calculated by the control module based on the signal from the Boost pressure sensor.

Desired Cylinder Air

--

240.00-280.00 mg/stk

This parameter displays the difference between the actual amount of cylinder air and the desired amount of cylinder air.

Desired Fuel Rail Pressure

--

42500.0-44500.0 kPa

6215.0-6265.0 psi

This parameter displays the desired fuel rail pressure as calculated by the control module. This value is calculated based on engine speed, engine load, and sensor inputs.

Desired Idle Speed

--

700-800 RPM

This parameter displays the desired engine idle speed as commanded by the control module.

Distance Since DPF Indicator ON without Regeneration

--

Varies

This parameter displays the mileage that has elapsed since the diesel particulate filter indicator was illuminated without a regeneration occurrence.

Distance Since Last DPF Regeneration

--

Varies

This parameter displays the mileage that has elapsed since the last diesel particulate filter regeneration has occurred.

DPF Differential Pressure Particulate Filter Pressure Variance

--

Varies

This parameter displays the percent calculated by the control module, based on the input from the exhaust gas temperature sensors when the particulate filter is full and needs a particulate filter regeneration.

DPF Differential Pressure Particulate Filter Pressure Variance

--

0.40-0.60 Volts

This parameter displays the voltage calculated by the control module, based on the input from the exhaust gas temperature sensors when the particulate filter is full and needs a particulate filter regeneration.

DPF Indicator Command

--

OFF

This parameter displays the commanded state of the dpf indicator lamp control circuit.

DPF Regen Command

--

0 Counts

The parameter displays the DPF regeneration command.

DPF Regen Flow Resistance

--

0.000 pa/m³/h

0.000 psi/cfm

This parameter displays the difference between the front and rear pressures at the DPF as calculated by the ECM.

DPF Regeneration Inhibit

--

No

The parameter displays if the DPF regeneration was inhibited.

DPF Regeneration Interrupted

--

No

The parameter displays if the DPF regeneration was interrupted.

DPF Soot Mass

--

2g-8g

This parameter displays the amount of calculated soot in exhaust particulate filter.

    

Cylinders 1-4 Pilot Injection Command

--

360-380 microseconds

This parameter displays the commanded on time of the fuel injectors for the pilot injection pulse. The scan tool will display a higher value for a longer injection pulse.

ECM Authentication Status

Ignition ON

Valid

This parameter displays the status of the control module this ignition cycle. The scan tool will display valid when an internal control module reset has occurred this ignition cycle. The scan tool will display invalid when no internal control module reset has occurred this ignition cycle.

ECM Challenge Status

Ignition ON

Invalid

This parameter displays the status of the control module this ignition cycle. The scan tool will display valid when an internal control module reset has occurred this ignition cycle. The scan tool will display invalid when no internal control module reset has occurred this ignition cycle.

ECM Response Source

Ignition ON

Normal

This parameter displays the status of the control module response this ignition cycle.

ECT Sensor

--

-39 to +140°C ( -38 to +284°F)

This parameter displays the temperature of the engine coolant based on input to the control module from the engine coolant temperature (ECT) sensor.

ECT Sensor

--

0-5 Volts

This parameter displays the voltage calculated by the control module from the engine coolant temperature (ECT) sensor.

EGR Position Command

--

40-55%

This parameter displays the percent of the duty cycle commanded by the control module.

EGR Solenoid Valve Command

--

40-55%

This parameter displays the percent of the EGR solenoid commanded by the control module.

EGR Solenoid Valve Command

--

OFF

This parameter displays the state of the control circuit for EGR solenoid as commanded by the control module.

Engine Load

Engine Idling

20-35%

This parameter displays the percent of the calculated engine load based on inputs to the control module from various engine sensors.

Engine speed at 2,500 RPM

15-25%

Engine Oil Level Switch

--

OK

This parameter displays the status of the engine oil level switch as determined by the control module. The control module uses this information to turn on the low engine oil lamp if the engine oil level remains approximately 1 quart low for a sufficient amount of time.

Engine Oil Pressure Switch

--

OK

This parameter displays the pressure of the engine oil calculated by the control module using a signal from the engine oil pressure (EOP) sensor.

Engine Run Time

Engine Operating

0:00:00

Increments when the engine is operating

This parameter displays the time elapsed since the engine was started.

Engine Speed

Engine Cranking

Greater than 60 RPM

This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position (CKP) sensor. If there is a CKP sensor DTC, the ECM calculates the engine speed from one of the camshaft position (CMP) sensors.

Engine Idling

Approximately 750-850 RPM

Exhaust Gas Temperature Sensor 1 or 2

--

EGT 1 - +110°C to +140°C ( +230°F to +284°F)

EGT 2 - +80°C to +120°C ( +176°F to +248°F)

This parameter displays the temperature of the exhaust gas calculated by the control module based on the input from the exhaust gas temperature sensors.

Exhaust Gas Temperature Sensor 1 or 2

--

EGT 1 - 1.00-1.15 Volts

EGT 2 - 0.90-1.10 Volts

This parameter displays the voltage calculated by the control module based on the input from the exhaust gas temperature sensors.

Fuel Filter Heater Command

--

OFF

This parameter displays the control module commanded state of the fuel heater control circuit.

Fuel Level Sensor

--

0-100%

This parameter displays the percent of fuel in the fuel tank calculated by the control module.

Fuel Level Sensor Left Tank or Fuel Level Sensor Right Tank

--

0-5 Volts

This parameter displays the voltage received by the control module from the sensor used to monitor the fuel level inside the fuel tanks.

Fuel Pressure Regulator 1

--

1300-1400 mA

This parameter displays the control modules commanded state of the fuel rail pressure regulator 1.

Fuel Pressure Regulator 2

--

500-600 mA

This parameter displays the control modules commanded state of the fuel rail pressure regulator 2.

Fuel Pressure Regulator 2 Control Circuit Command

--

20%

This parameter displays the percent of the fuel rail pressure regulator duty cycle commanded by the control module.

Fuel Pump Command

--

34%

This parameter displays the percent of the control modules commanded state of the fuel pump.

Fuel Pump Relay Command

Ignition ON, engine OFF

Fuel pump on for 2 seconds

This parameter displays the control modules commanded state of the fuel pump relay control circuit.

Engine idling

On

Fuel Rail Pressure Sensor

--

42800-43800 kPa

(6207-6352 psi)

This parameter displays the fuel rail pressure calculated by the control module using the signal from the fuel rail pressure (FRP) sensor.

Fuel Rail Pressure Sensor

--

1.40-1.50 Volts

This parameter displays the voltage of the fuel rail pressure calculated by the control module using the signal from the fuel rail pressure (FRP) sensor.

Fuel Temperature Sensor

--

25 to 40°C (77 to 104°F)

This parameter displays the fuel temperature calculated by the control module based on input from the fuel temperature sensor.

Fuel Temperature Sensor

--

2.80 Volts

This parameter displays the voltage calculated by the control module based on input from the fuel temperature sensor.

Generator F Terminal Signal

--

25-35%

This parameter displays the commanded state of the generator by the control module.

Glow Plug

--

0%

This parameter displays the percent of the voltage supply to the glow plugs as measured by the control module.

Glow Plug Command

--

OFF

This parameter displays the control module commanded state of the glow plug.

Glow Plug Lamp Command

--

OFF

This parameter displays the commanded state of the glow plug lamp circuit by the control module.

IA Flow Valve Motor Command

--

55-65%

This parameter displays the percent of the control modules commanded state of the intake air flow valve.

IAT Sensor 1 or Sensor 2

--

-39 to +140°C (-38 to +284°F)

This parameter displays the temperature of the air entering the engine air duct calculated by the control module based on the input from the intake air temperature sensors.

Ignition 0 Signal

Ignition ON

Active

This parameter displays the voltage measured at the ignition 0 circuit of the control module. Voltage is applied to the control module when the ignition switch is in the ignition 0 position.

Ignition 1 Signal

Ignition ON

Active

This parameter displays the voltage measured at the ignition 1 circuit of the control module. Voltage is applied to the control module when the ignition switch is in the ignition 1 position.

Immobilizer Auto Learn Counter

--

0 Counts

This parameter displays the status of the theft deterrent system password learn.

Immobilizer Password Learn Enabled

Ignition ON

No

This parameter indicates the status of the theft deterrent system password learn.

Immobilizer Password Programmed

--

Yes

This parameter indicates the status of the immobilizer system. The scan tool will display YES if the immobilizer system is ready to be programmed.

Immobilizer Security Code Accepted

Ignition ON

No

This parameter indicates the status of the theft deterrent system security code.

Immobilizer Security Code Lockout

Ignition ON

Active

This parameter Indicates if the theft deterrent system is disabling fuel delivery.

Immobilizer Security Code Programmed

--

No

This parameter indicates the status of the security system.

Immobilizer System State

--

Release

This parameter indicates the status of the immobilizer system.

MAF Sensor

--

On

This parameter indicates the quantity calculated by the control module based on a signal from the mass air flow (MAF) Sensor.

Main Injection Fuel Rate

--

6.5 mm³

This parameter displays the air to fuel ratio based on the oxygen sensor inputs. The ECM uses the fuel trims to adjust fueling in order to attempt to maintain a certain air fuel ratio.

Main Injection Timing

--

On

This parameter displays the current timing of the main injection pulse as calculated by the control module.

MAP Sensor

--

95-104 kPa

This parameter indicates the manifold absolute pressure inside the engine as calculated by the control module based on the signal from the manifold absolute pressure (MAP) sensor.

MIL Command (MIL)

--

Off

This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit by the control module.

Pilot Injection Trim Average

--

10-36 microseconds

This parameter displays the average commanded on time of the fuel injectors for the pilot injection pulse.

Park/Nuetral Position Switch

--

Park/Neutral

This parameter displays whether the transmission range selector is in park/neutral or in gear.

Starter Relay Command

--

Off

This parameter displays the commanded state of the starter relay.

Turbocharger Vane Position Solenoid Valve Command

TCC Enable Solenoid Command ON

80%

This parameter displays the percent of the vane position control solenoid from the control module.

Throttle Position Sensor

--

55-70%

This parameter displays the percent of throttle opening as calculated by the control module using information from the TP sensor.

Vehicle Speed Sensor

--

0 Km/h

0 mph

This parameter displays the speed of the vehicle as calculated by the transmission control module (TCM) from information received from the vehicle speed sensor (VSS).

Water In Fuel Sensor

--

Off

This parameter displays the commanded state of the water in fuel lamp by the control module.

Engine Control Module (ECM) Scan Tool Output Controls

Output Control

Description

A/C Compressor Clutch Relay

Note: The A/C Relay Command parameter may not change states when using this output control.

This function activates the A/C compressor relay. The normal commanded state of the A/C relay is OFF. The A/C compressor will turn ON/OFF when commanded ON/OFF. The system remains in the commanded state for approximately 5 seconds. The engine control module (ECM) will inhibit the operation of the A/C relay when the ambient air temperature is low.

Alternator Lamp

This function activates the alternator lamp. The glow plug indicator lamp will remain illuminated until cancelled by the scan tool.

Aux Heater Relay 1

Note: This function is only allowed with the ignition ON, engine OFF.

This function controls the aux heater relay 1.

Aux Heater Relay 2 & 3

Note: This function is only allowed with the ignition ON, engine OFF.

This function controls the aux heater relays 2 and 3.

Cooling Fan Relay 1

This function controls the low speed cooling fan relay. When commanded ON, the cooling fan will turn ON at low speed for approximately 5 seconds.

Cooling Fan Relays 2 & 3

This function controls the high speed cooling fan relay. When commanded ON, the cooling fan will turn ON at high speed.

Cooling Fan Relays 1, 2 & 3

This function controls the high speed cooling fan relay. When commanded ON, the cooling fan will turn ON at high speed.

Cranking Speed Test

Note: This function is only allowed with the ignition ON, engine OFF.

This function enables the ECM to detect engine speed of each cylinder without activating the fuel injectors.

Cruise Lamp

This function activates the cruise control lamp. The cruise control indicator lamp will remain illuminated until cancelled by the scan tool.

Desired Idle Speed Adjustment

Note: This function is only allowed with the engine idling.

This function adjusts the engine speed in 25, 100, or 500 RPM increments between 600-1500 RPM. The Device Control will not change unless changed or cancelled by the scan tool.

DPF Indicator

This function activates the DPF lamp. The DPF indicator lamp will remain illuminated until cancelled by the scan tool.

DPF Reset Replace DPF

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values for the diesel particulate filter in the ECM after the DPF has been replaced.

DPF Reset Replace ECM

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values for the diesel particulate filter in the ECM after the ECM has been replaced.

DPF Reset Replace Injectors

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values for the diesel particulate filter in the ECM after one or more injectors have been replaced.

DPF Reset Replace Pressure Sensor

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values for the diesel particulate filter in the ECM after the DPF pressure sensor has been replaced.

EGR Solenoid Valve

This function opens or closes the exhaust gas recirculation (EGR) solenoid. The EGR solenoid increases or decreases in 10 percent increments. The device control will not change unless changed or cancelled by the scan tool.

Engine High Temp. Lamp

This function activates the engine high temperature lamp. The engine high temperature lamp will remain illuminated until cancelled by the scan tool.

Engine Oil Life Reset

This function turns OFF the change oil lamp and resets the values in the ECM.

Fuel Filter Heater

This function activates the fuel heater relay ON or OFF. The Device Control will not change unless changed or cancelled by the scan tool.

Fuel Pump Enable

Note: This function is only allowed with the ignition ON, engine OFF.

This function activates the fuel transfer pump or prime pump (depending on application) ON or OFF. The Device Control will not change unless changed or cancelled by the scan tool.

Fuel Quantity Test

Note: This function is only allowed with the engine idling.

This function enables the engine control module (ECM) to detect the fuel quantity in each cylinder.

Fuel Trim Reset

This function resets the fuel trim data in all fuel trim cells.

Generator L-Terminal

Note: This function is only allowed with the engine idling.

This function controls the system voltage. When commanded ON, normal system voltage output is present. When commanded OFF, system voltage output is no longer present, Ignition 1 signal continues to drop, Gen L-Terminal goes to OFF and Gen F-Terminal continues to drop.

Glow Plugs

This function activates the Glow Plug Controller ON or OFF. The Device Control will be aborted after 12 seconds for the first activation, and after 5 seconds for every other activation. The Device Control is inhibited if the engine is running.

Glow Plug Lamp

This function activates the glow plug indicator lamp. The glow plug indicator lamp will remain illuminated until cancelled by the scan tool.

Idle Speed Control

Note: This function is only allowed with the engine idling.

This function adjusts the engine speed in 25, 100, or 500 RPM increments between 600-1500 RPM. The Device Control will not change unless changed or cancelled by the scan tool.

Idle Speed Test

Note: This function is only allowed with the engine idling.

This function enables the ECM to detect engine speed of each cylinder without making any fuel correction.

Malfunction Indicator Lamp (MIL)

This function activates the malfunction indicator lamp (MIL). The MIL will remain illuminated until cancelled by the scan tool.

Reset Injection Value - All Cyl.

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after all the fuel injectors have been replaced.

Reset Injection Value - Cyl. 1

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after cylinder 1 fuel injector has been replaced.

Reset Injection Value - Cyl. 2

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after cylinder 2 fuel injector has been replaced.

Reset Injection Value - Cyl. 3

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after cylinder 3 fuel injector has been replaced.

Reset Injection Value - Cyl. 4

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after cylinder 4 fuel injector has been replaced.

Reset Injection Value - ECM

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned fuel injector values in the ECM after the ECM has been replaced.

Throttle Blade Control

Note: This function is only allowed with the ignition ON, engine OFF.

This function opens or closes the throttle blade. The throttle blade increases or decreases in 10 percent increments. The scan tool initiates the test when the following conditions are met:

    • There are no vehicle speed sensor DTCs set.
    • The vehicle speed is 0 km/h (0 mph).
    • The ignition is ON, with the engine OFF.
    • The ECM is not commanding a throttle learn.

The system remains in the commanded state until cancelled by the scan tool.

Turbocharger Vane Position Solenoid Vlave

Note: This function is only allowed with the engine idling.

Cycles the turbocharger vane position solenoid to 95 percent boost and back to 0 percent boost. The device control is limited to engine speeds less than 2,000 RPM.