Lotus Elise / Lotus Exige. Instruction - part 44

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Lotus Service Notes   

 

 

  Section EMP

VIN Not Programmed or Incompatible – ECU/PCM            P0630

Description

The ECM programming includes the Vehicle Identification Number (VIN).  This operation is performed using 

the Lotus Scan tool.

Enable Criteria:

# Engine running (for up to 4 seconds)

Disable Criteria: None

Potential failure modes:

# VIN not programmed

# Incompatible VIN programmed

Throttle Actuator Control Range/Performance              P0638

Description

The single throttle butterfly valve, mounted at the inlet to the intake plenum, is operated by a stepper motor 

under the command of the engine ECU.  The valve moves through a range of nearly 90° and should display 

100% at full throttle and around 2% at idle.

Monitor: Continuous

Enable Criteria:

# Engine running

Disable Criteria: 

# Electronic throttle fault(s) present

Potential failure modes:

# Blocked throttle body

# Damage to throttle actuator

Notes: A mechanically sprung 7% throttle opening may be imposed.  

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Lotus Service Notes   

 

 

  Section EMP

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Throttle Actuator Control Motor Circuit/Open               P2100

Description

The throttle actuator stepper motor operates on 12 volts.

Monitor: Continuous

Enable Criteria: None

Disable Criteria: None

Potential failure modes:

#Throttle actuator control motor open circuit

Throttle Actuator Control Motor Circuit/Low                P2102 

Monitor: Continuous

Enable Criteria: None

Disable Criteria: None

Potential failure modes:

# Throttle actuator control motor short to ground

Throttle Actuator Control Motor Circuit/High               P2103

Monitor: Continuous

Enable Criteria: None

Disable Criteria: None

Potential failure modes:

# Throttle actuator control motor short to supply voltage

Throttle Actuator Control System – Forced Idle              P2104

Description

If a problem is detected which could result in faster engine speed than commanded by the pedal, the actuator 

is switched out, allowing the throttle valve to default to a 6% mechanically sprung setting.  This provides a fast 

idle speed which may be used to effect a 'limp home' mechanism.

Monitor: Continuous

Enable Criteria: Engine running

Disable Criteria: None

Potential failure modes:

# Electronic throttle fault

Note: This code indicates action taken by the ECU, and will always be accompanied by another code which 

has caused this action.

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Lotus Service Notes   

 

 

  Section EMP

Throttle Actuator Control System – Forced Engine Shutdown    P2105

Description

If a problem is detected which could result in engine speed runaway, or if sufficient control of engine speed is 

lost, the ECU switches off the fuel injectors in order to stop the engine.

Monitor: Continuous

Enable Criteria: Engine running

Disable Criteria: None

Potential failure modes:

# Electronic throttle fault

Note: This code indicates action taken by the ECU, and will always be accompanied by another code which 

has caused this action.

Throttle Actuator Control System – Forced Limited Power      P2106

Description

If a problem is detected which could result in engine speed control difficulties, the ECU will limit throttle opening 

to a maximum of 15%.

Monitor: Continuous

Enable Criteria: Engine running

Disable Criteria: None

Potential failure modes:

# Electronic throttle fault

Note: This code indicates action taken by the ECU, and will always be accompanied by another code which 

has caused this action.

Throttle Actuator Control Module Processor                  P2107

Description

The ECU contains two processors dedicated to the throttle pedal and throttle valve potentiometers.

Monitor: Continuous

Enable Criteria: Engine running

Disable Criteria: None

Potential failure modes:

# ECU internal fault

# Incorrect ECU programming

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  Section EMP

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Throttle Actuator Control Module Performance              P2108

Monitor: Continuous

Enable Criteria: Engine running

Disable Criteria: None

Potential failure modes:

# ECU internal failure

# Short circuit to throttle actuator

Pedal Position Sensor 'D' Circuit Low                    P2122

Description

Two potentiometers are built into the throttle pedal  unit in order to provide a throttle demand signal to the ECU.  

Note that the potentiometers operate on 5 volts.

Enable Criteria: None

Disable Criteria: None

Potential failure modes:

# Signal short circuit (< 0.283 V)

# Reference voltage open circuit

# Reference voltage short to ground

# Sensor failure

Notes: A maximum throttle opening of 15% may be imposed due to this single code.  In the case of multiple 

codes, a mechanically sprung 7% opening may be applied.

Pedal Position Sensor 'D' Circuit High                    P2123

Enable Criteria: None

Disable Criteria: None

Potential failure modes:

# Signal open circuit (> 4.487 V)

# Reference voltage open circuit

# Reference voltage short to ground

# Sensor failure

Notes: A maximum throttle opening of 15% may be imposed due to this single code.  In the case of multiple 

codes, a mechanically sprung 7% opening may be applied.

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