Lotus Eleven/Elise/Exige. Manual - part 41

 

 

Lotus Service Notes   

 

 

  Section EMP

Page 19

Potential failure modes:

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

•  Catalyst

P0139 

Set when the sensor fails to reach 650mV after 1.9 seconds of P.E or when the sensor fails to drop below 

150mV after 5 seconds of DFCO ('06 M.Y.; Set when sensor fails to switch between 250mV and 650mV with 

sufficient rapidity).

Enable Criteria:

•  Engine run time > 200 seconds

•  Coolant temperature > 60°C (140°F)

•  Open loop fuel control

•  DFCO (Deceleration Fuel Cut Off) followed by idle operation for 'lean to rich' switch

•  DFCO for 'rich to lean' switch

Disable Criteria:

P0116, P0117, P0118            – Coolant Temperature Sensor faults

P0201, P0202, P0203, P0204      – Injector faults

P0300, P0301, P0302, P0303, P0304 – Misfire faults

P1301, P1302                 – Misfire faults causing emission or catalyst damage

Monitor: Continuous, until the test is either passed or failed

Potential failure modes:

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

•  Catalyst

P0140 

Set when the sensor fails to switch above 557mV and below 400mV within 60 seconds.

Enable Criteria:

•  Engine run time > 30 seconds

•  Engine is not at idle

•  Engine is in closed loop fuel control

Monitor: Continuous

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

P0141 

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

checks.

Enable Criteria: Engine run time > 60 seconds

Monitor: Continuous

Potential failure modes:

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

Notes:

•  The MIL will be illuminated if the fault is present for 2 consecutive trips.

•  Further information on the sensor may be found in Toyota 1ZZ-FE, 2ZZ-GE manual RM733E (B120T0327J)

pages DI-63 to DI-66

Page 20

 

 

Lotus Service Notes   

 

 

  Section EMP

 

Fuel Control System Too Lean Or Rich      P0171

                                P0172

P0171  System Too Lean

P0172  System Too Rich

Description

The oxygen sensor sends a signal to the ECU corresponding to the exhaust gas oxygen content enabling the 

ECU to maintain a 14.7:1 air/fuel ratio under normal driving conditions. The ECU can make fuel corrections 

of ± 17% to the calculated fuel demand. If the ECU determines a rich condition exists (oxygen sensor above

0.450mV), it will decrease the calculated fuel demand to maintain a 14.7:1 ratio. If the ECU determines a lean 

condition exists (oxygen sensor below 0.450mV), it will increase the calculated fuel demand to maintain a 

14.7:1 ratio.

Enable Criteria

•  Fuel Trim condition enabled

•  Closed loop fuelling enabled

•  Engine speed > 1100 rpm

•  MAF > 6 g/sec

•  Engine load < 70 %

•  Altitude < 8000 ft (2438 m), Baro > 756 mbar

•  Inlet air temperature > -10°C (14°F)

Disable Criteria

P0106, P0107, P0108                               – Baro sensor faults

P0111, P0112, P0113                                – Air Intake Sensor faults

P0131, P0132, P0133, P0134, P0135                     – Oxygen sensor faults

P0300, P0301, P0302, P0303, P0304                      – Misfire faults

P0441, P0442, P0443, P0447, P0448, P0450, P0451, P0455, P0456   – EVAP faults

Monitor: Continuous

Malfunction Criteria

P0171 

This code is set when the calculated fuel demand has been increased to its maximum limit of 17% and the 

system still cannot maintain an air/fuel ratio of 14.7:1 under normal driving conditions.

Potential failure modes:

•  Fuel Pressure too low

•  Air leak in system

•  Water in fuel

•  Exhaust leak / crack before front oxygen sensor

•  Injector fault

•  Sensor connector and wiring for signs of corrosion or loose connections

P0172 

This code is set when the calculated fuel demand has been decreased to its minimum limit of -17% and the 

system still cannot maintain an air/fuel ratio of 14.7:1 under normal driving conditions.

Potential failure modes:

•  Fuel Pressure too high

•  Leaking fuel injector

•  Restriction in the exhaust system or air intake / filter

•  Erratic throttle position sensor

Notes:

•  The MIL will be illuminated if the fault is present for 2 consecutive trips.

•  Further information on the sensor may be found inToyota 1ZZ-FE, 2ZZ-GE manual RM733E (B120T0327J)

pages DI-67 to DI-72

 

 

Lotus Service Notes   

 

 

  Section EMP

Page 21

Fuel Injection System            P0201

                          P0202

                          P0203

                          P0204

P0201  Injector Circuit/Open – Cylinder 1

P0202  Injector Circuit/Open – Cylinder 2

P0203  Injector Circuit/Open – Cylinder 3

P0204  Injector Circuit/Open – Cylinder 4

Description

The ECU has four injector driver circuits, each of which controls an injector. When the engine is running the 

ECU continuously monitors the injector circuit feedback signals. The feedback signal should be low when the 

injector is ON and high voltage when the injector is OFF.

Component connections

Injector    ECU Pin    ECU Connector

1        25 (J1)    52 Way (Right)

2        51 (K4)    52 Way (Right)       

'06 M.Y. in brackets

3        14 (K3)    52 Way (Right)

4        40 (K2)    52 Way (Right)

Malfunction Criteria

The operation of all the injector codes is the same, the last digit relates to the injector involved i.e. a code P0203 

indicates there is a problem with injector number 3.

Enable Criteria: Engine running

Monitor: Continuous

Limp home:

•  Limit maximum engine speed to 6000rpm

•  Return the fuel system to open loop fuel control

Potential failure modes:

Sensor connector or wiring corroded or loose connections

Notes:

•  The MIL will be illuminated if the fault is present for 2 consecutive trips.

•  If an injector goes short circuit it is likely that the ECU injector driver will be damaged.

Page 22

 

 

Lotus Service Notes   

 

 

  Section EMP

Misfire                      P0300

                          P0301

                          P0302

                          P0303

                          P0304

P0300  Random/Multiple Cylinder Misfire Detected

P0301  Cylinder 1 Misfire Detected

P0302  Cylinder 2 Misfire Detected

P0303  Cylinder 3 Misfire Detected

P0304  Cylinder 4 Misfire Detected

Description

A misfiring cylinder can be detected by analysing crank speed variation. As a result of a combustion event there 

will be a net acceleration of the crankshaft. Subsequent to a misfire event the engine will decelerate over the 

period following the missed cylinder event.

Speed changes can be characterised by observing changes in the time period for a fixed angle of rotation after 

firing events. A significant change in this period, assessed by comparison to previous periods, may be attributed 

to misfire on a known cylinder. 

Component connections                    '06 M.Y. in brackets

Connector    Description          ECU Pin                    ECU Connector

1          Supply Voltage        Coil 1   Coil 2   Coil 3   Coil 4 

2          Ignition Coil Feedback   22 (F3)  22 (F3)  22 (F3)  22 (F3)  52 Way (Right)

3          Coil Output (Logic)     52 (G1)  26 (G4)  47 (G3)  48 (G2)  52 Way (Right)

4          Ground                     

Malfunction Criteria

The operation of all the misfire codes is the same, the last digit relates to the misfire involved i.e. a code P0303 

indicates there is a problem with coil number 3. P0300 indicates the misfire is random and not linked to one 

particular cylinder.

Enable Criteria:

•  Battery voltage between 10 – 16 V

•  Coolant temperature between -10 – 120°C (14 – 248°F)

•  Engine speed between 660 – 8010rpm

•  Engine speed transient > 15rpm

•  Altitude < 8000 ft (2438 m) / Baro > 756mbar

•  Fuel level > 5 litres (1.3 US gallons)

•  Engine load between 15 – 48% depending on engine speed

Disable Criteria: DFCO enabled (Deceleration Fuel Cut Off)

Monitor: Continuous

Limp home:

•  Limit maximum engine speed to 6000 rpm

•  Return the fuel system to open loop

•  ECU may deactivate two cylinders, the misfiring cylinder and it’s matched other i.e. 1 & 4 or 2 & 3.

Potential failure modes:

•  Injector related codes, as these can cause misfire codes to be set.

•  VVT or VVL codes set

•  Sensor connector and wiring for signs of corrosion or loose connections

•  Spark plug / Cylinder compression

•  Cam timing / Damage to rocker arm assembly