Lotus Evora. Manual - part 25

 

 

Lotus Service Notes   

 

 

  Section EMR

Malfunction Criteria: 

•  Set when the sensor fails to switch from a Lean to a Rich condition or switch from a Rich to a Lean condition

in a sufficiently timely manner.  A selection of switches is used to determine the average times.

“highlighted section removed” 

Potential failure modes:

•  Sensor connector and wiring should be checked for corrosion and loose connections

•  Sensor contaminated, possibly from fuel, improper use of RTV, engine oil or coolant

Diagnostic Mask:

•  The MIL will be illuminated if these faults are present for 2 consecutive trips.

P0134 (Bank1) or P0154 (Bank2)

Monitor:

•  Until either passed or failed.

Enable Criteria:

•  Engine run time > 30 seconds

•  Engine is not at idle

•  Engine is in closed loop fuel control

•  O2 sensor ready

Malfunction Criteria:

•  Set when the sensor fails to switch above 673mV and below 400mV within a 60 second period.

Potential failure modes:

•  Sensor connector and wiring should be checked for corrosion and loose connections.

•  Gas leak in exhaust system

Diagnostic Mask:

•  The MIL will be illuminated if these faults are present for 2 consecutive trips.

P0135, P0155 

Monitor:

•  Continuous

Enable Criteria:

•  Engine run time > 20 seconds

Malfunction Criteria:

•  Set when the heater output is greater than 1900mA or less than 250mA for 1.5 seconds, for 40 consecutive

checks.

Potential failure modes:

•  Sensor connector and wiring should be checked for corrosion and loose connections.

Diagnostic Mask:

•  The MIL will be illuminated if these faults are present for 2 consecutive trips.

 

2009/02

 

 

Lotus Service Notes   

 

 

  Section EMR

O2 Sensor (Post Catalyst)

P0137  O2 Sensor Circuit Low Voltage (Bank 1)

P0138  O2 Sensor Circuit High Voltage (Bank 1)

P0139  O2 Sensor Circuit Slow Response (Bank 1)

P0140  O2 Sensor Circuit No Activity Detected (Bank 1)

P0141  O2 Sensor Heater Circuit (Bank 1)

P0157    O2 Sensor Circuit Low Voltage (Bank 2)

P0158    O2 Sensor Circuit High Voltage (Bank 2)

P0159    O2 Sensor Circuit Slow Response (Bank 2)

P0160    O2 Sensor Circuit No Activity Detected (Bank 2)

P0161    O2 Sensor Heater Circuit (Bank 2)

Description 

The oxygen sensors separately monitor the oxygen content in the exhaust gases of each bank of the engine. 

Each sensor is electrically heated to improve response from start. 

The sensor consists of a zirconia electrode between two platinum plates. When zirconia comes into contact with 

oxygen, it becomes an electrical conductor. The exhaust gases passes through louvers in the sensor. One plate 

is in contact with the outside air and the other plate is in contact with the exhaust gases. The platinum plate in 

contact with the air is electrically negative due to the oxygen in the atmosphere and the plate in contact with 

the exhaust gases is electrically positive. This will cause a difference in electrical potential to develop between 

the two plates. Thus the voltage across the platinum plates ranges approximately from 100 millivolts to 900 

millivolts, depending on the oxygen content of the exhaust gases. Thus when the air/fuel mixture is rich, the 

oxygen sensor output will be high. If the air/fuel mixture is lean, the oxygen sensor output will be low. The post 

catalyst oxygen sensor performance is a good indicator of catalyst efficiency.

Sensor connections

Sensor Connector    Description      ECU Pin    ECU Connector

1 Bank 1         Signal              H1     48 Way (Centre)

2 Bank 1                Ground             K4     48 Way (Centre)     

3 Bank 1         Heater              K1        48 Way (Centre)

4 Bank 1          Battery Voltage         -             -

1 Bank 2                     Signal            H2     48 Way (Centre)

2 Bank 2         Ground          K4     48 Way (Centre)

3 Bank 2         Heater          K2     48 Way (Centre)

4 Bank 2         Battery Voltage      -          -

Sensor characteristics

Normal operating range is 0 – 1000mV

P0137, P0157 

Monitor: 

•  Continuous

Enable Criteria:

•  None

Disable Criteria: 

•  DFCO (Deceleration Fuel Cut Off)

•  AE DE (Acceleration Enrichment or Deceleration Enleanment)

•  Misfire

Malfunction Criteria:

•  Set when the sensor operates below 15mV for more than 1.5 seconds consecutively for a specified number

of times.

2009/02

 

 

Lotus Service Notes   

 

 

  Section EMR

Potential failure modes:

•  Check and rectify any pre catalyst sensor fault code, as they may be causing the fault code to be set

•  Sensor wire shorted to ground

•  Catalyst

Diagnostic Mask:

•  The MIL will be illuminated if these faults are present for 2 consecutive trips.

P0138, P0158 

Monitor: 

•  Continuous

Enable Criteria: 

•  Engine running

Disable Criteria: 

•  None

Malfunction Criteria:

•  Set when the sensor operates above 1200mV for more than 1.5 seconds consecutively for a specified

number of times.

Potential failure modes:

•  Check and rectify any front sensor fault code, as they may be causing the fault code to be set

•  Catalyst

Diagnostic Mask:

•  The MIL will be illuminated if these faults are present for 2 consecutive trips.

P0139, P0159 

2009/02

 

 

Lotus Service Notes   

 

 

  Section EMR

P0140, P0160 

Monitor: 

•  Continuous

Enable Criteria:

•  Engine run time > 30 seconds

•  Engine is not at idle

•  Engine is in closed loop fuel control

•  Oxygen sensors ready

Disable Criteria:  

•  None

Malfunction Criteria:

•  Set when the sensor fails to switch above 673mV and below 400mV within 60 seconds.

Potential failure modes:

•  Check and rectify any front sensor fault code, as they may be causing the fault code to be set

•  Sensor connector and wiring should be checked for corrosion and loose connections

•  Catalyst

•  Gas leak in exhaust system

Diagnostic Mask:

•  The MIL will be illuminated if these faults are present for 2 consecutive trips.

P0141, P0161 

Monitor: 

•  Continuous

Enable Criteria: 

•  Engine run time > 20 seconds

Disable Criteria:  

•  None

Malfunction Criteria:

•  Set when the heater output is greater than 1900mA or less than 250mA for 1.5 seconds, for 40 consecutive

checks.

Potential failure modes:

•  Sensor connector and wiring should be checked for corrosion and loose connections

Diagnostic Mask:

•  The MIL will be illuminated if a fault is present for two consecutive trips.

 

2009/02