ECM Correction (the engine control unit)
ECM (the engine control unit) has the function of correcting parameters that affect the nature of the control signal. This feature allows the engine management system to (EMS) to keep the toxicity of exhaust gases within the established norms and to optimize the operation of the engine in the field of multi-parameter characteristics.
The components for which parameter adjustments can be made are the following devices:
- APP sensor (accelerator pedal position)
- Oxygen sensor (HO2S)
- MAF sensor (mass air flow) /IAT (intake air temperature)
- CKP sensor (crankshaft position)
- Electronic throttle body
UHEGO/HEGO and MAF sensors (mass air flow) /IAT (intake air temperature)
The fuel management strategy uses several adaptive data maps. ECM-determined fuel management strategy (the engine control unit), includes a short-term correction and a long-term collection. ECM (the engine control unit) monitors the HO2S performance while it is running. In addition, the ECM monitors the current correction made to these sensors.
In cases where the correction parameters are out of range, the ECM (the engine control unit) stores a fault code. Simultaneous ECM (the engine control unit) records engine speed, engine load and intake air temperature.
CKP sensor (crankshaft position)
CKP sensor signal characteristics (crankshaft position) stored by the ECM (the engine control unit). This allows the ECM (the engine control unit) calculate correction parameters and support the function of detecting misfires in cylinders. Since all flywheels and CKP sensors (crankshaft position) slightly different from each other, then when replacing (or when removing and installing) of any of the named components, the correction parameters must be updated. Correction parameters must also be updated when replacing the ECM (the engine control unit). ECM (the engine control unit) supports four types of CKP sensor signal correction (crankshaft position) by determining the position of the crankshaft (flywheel). Each type of correction refers to a certain range of crankshaft speed. The crankshaft speed ranges are characterized in the table:
Correction | Frequency of rotation of a cranked shaft, rpm |
1 | 1800 - 3000 |
2 | 3001 - 3800 |
3 | 3801 - 4600 |
4 | 4601 - 5400 |
Missing Flash Detection
Legislation requires that the ECM (the engine control unit) could detect misfires in cylinders. The ECM must distinguish between two types of missed flashes (levels). The first type of skipping outbreaks is one in which there is an increase in the total release of toxic substances by 1.5 times when determining their concentration in accordance with the Federal FTP methodology. Skipping flashes of the second type can damage the catalytic converter.
ECM (the engine control unit) tracks the number of occurrences of skips in two specific speed ranges. If the number of detected ECMs (the engine control unit) misses flashes in any of the speed ranges, exceeds the preset value for two consecutive trips, then the ECM (the engine control unit) will record the fault code and related parameters: crankshaft rotation speed, engine load and coolant temperature. In addition, ECM (the engine control unit) monitors the number of flashes skipped per 200 revolutions of the crankshaft. These leaks are judged on their ability to damage catalytic converters. If the number of skipped flashes exceeds a certain value, then the ECM (the engine control unit) will record the status code of the threat to the converter and related parameters: crankshaft rotation speed, engine load and coolant temperature.
The signal shape of the crankshaft position sensor depends on the speed of the flywheel relative to the sensor tip. With each passage of the tooth of the driving wheel past the tip of the sensor, a sinusoidal signal is formed in the latter. ECM (the engine control unit) determines the change in the speed of rotation of the flywheel (crankshaft) by changing the shape of the sinusoidal signal coming from the sensor.
Analysis of the received signal allows the ECM (the engine control unit) to detect the fact of missed flash. At this point in time, the ECM (the engine control unit) evaluates the degree of change in the signal of the crankshaft position sensor and assigns a coefficient of unevenness to it. The value of the coefficient of unevenness can be monitored in real time using the T4. ECM (the engine control unit) analyzes the signal by several parameters and decides whether the event is counted or not. ECM (the engine control unit) can establish the fact of a misfire and assign a coefficient of unevenness in relation to each individual cylinder.
Diagnosis with T4
ECM (the engine control unit) saves fault data as DTC (diagnostic trouble codes) , referred to as 'P' codes. 'P' codes are defined by regulations for OBD (on-board self-diagnosis system) and along with their respective environmental conditions and freeze frame data can be read out by means of a third party diagnostic tool or T4. The T4 is also capable of real-time reading of sensor data, setpoints currently in use, and current fuel, ignition and idle settings.
P code number | Component/Signal | Description of the fault |
P0011 | CMP (camshaft position) /CKP (crankshaft position) /VVT | Position Error VVT Lag Position Signal High for CMP (camshaft position) /CKP (crankshaft position) row A |
P0012 | CMP (camshaft position) /CKP (crankshaft position) /VVT | Position Error VVT Lag Position Signal Low for CMP (camshaft position) /CKP (crankshaft position) row A |
P0021 | CMP (camshaft position) /CKP (crankshaft position) /VVT | Position Error VVT Lag Position Signal High for CMP (camshaft position) /CKP (crankshaft position) row B |
P0022 | CMP (camshaft position) /CKP (crankshaft position) /VVT | Position Error VVT Lag Position Signal Low for CMP (camshaft position) /CKP (crankshaft position) row B |
P0026 | VVT | Bank A Fault Signal Low/High |
P0028 | VVT | Bank B Fault Signal Low/High |
P0031 | UHEGO | Bank A Heater Control Circuit Low |
P0032 | UHEGO | Bank A Heater Control Circuit High |
P0051 | UHEGO | Bank B heater control circuit low |
P0052 | UHEGO | Bank B Heater Control Circuit High |
P0069 | HAC | Characteristic / sensor circuit |
P0071 | Outdoor temperature sensor | Characteristic |
P0072 | Outdoor temperature sensor | Low signal level at the circuit input |
P0073 | Outdoor temperature sensor | High level signal at the input of the circuit |
P0075 | VVT | Open circuit in row A |
P0076 | VVT | Short to ground in row A circuit |
P0077 | VVT | Short circuit to battery in bank A circuit |
P0081 | VVT | Open circuit in row B |
P0082 | VVT | Short to ground in bank B circuit |
P0083 | VVT | Short to battery in bank B circuit |
P0087 | Fuel system | Minor malfunction |
P0088 | Fuel system | Major malfunction |
P0089 | Fuel system | Interference |
P0093 | Fuel system | Significant leak |
P0096 | IAT (intake air temperature) | Sensor characteristic |
P0101 | AFM | Circuit characteristic |
P102 | AFM | Low signal level at the circuit input |
P103 | AFM | High level signal at the input of the circuit |
P0106 | MAP (manifold absolute pressure) | Sensor characteristic |
P0107 | MAP (manifold absolute pressure) | Low signal level at the circuit input |
P0108 | MAP (manifold absolute pressure) | High level signal at the input of the circuit |
P0111 | IAT (intake air temperature) | Constantly high / low signal level when starting the engine, high level |
P0112 | IAT (intake air temperature) | Low signal level at the input of the sensor circuit 1 |
P0113 | IAT (intake air temperature) | High signal level at the input of the sensor circuit 1 |
P0116 | ECT (coolant temperature) | Invalid signal |
P0117 | ECT (coolant temperature) | Low signal level at the circuit input |
P0118 | ECT (coolant temperature) | High level signal at the input of the circuit |
P0121 | Throttle circuits 1 and 2 | Range/Characteristic |
P0122 | Throttle circuit 1 | Low input level |
P0123 | Throttle circuit 1 | High input level |
P0125 | ECT (coolant temperature) | Insufficient coolant temperature for feedback control system |
P0128 | Thermostat control circuit | Low coolant temperature - thermostat stuck open |
P0131 | UHEGO | Short to ground in row A circuit |
P0132 | UHEGO | Short circuit to battery in bank A circuit |
P0133 | UHEGO | Slow response for row A |
P0136 | HEGO | Parameter setting for row A |
P0137 | HEGO | Short to ground in row A circuit |
P0138 | HEGO | Short circuit to battery in bank A circuit |
P0139 | HEGO | Slow response for row A |
P0140 | HEGO | No signals for row A |
P0141 | HEGO | Malfunction in a chain of management of a heater of number A |
P0150-1A | HEGO | Low impedance row A element |
P0151 | UHEGO | Short to ground in bank B circuit |
P0152 | UHEGO | Short to battery in bank B circuit |
P0153 | UHEGO | Slow response for row B |
P0154-00 | UHEGO | Slow response for row B |
P0156 | HEGO | Parameter setting for row B |
P0157 | HEGO | Short to ground in bank B circuit |
P0158 | HEGO | Short to battery in bank B circuit |
P0159 | HEGO | Slow response for row B |
P0160 | HEGO | No Signals for Row B |
P0161 | HEGO | Malfunction in a chain of management of a heater of number B |
P00171 | Electronic fuel mixture control | Excessive lean in row A |
P0172 | Electronic fuel mixture control | Excessive enrichment in series A |
P0174 | Electronic fuel mixture control | Excessive lean in bank B |
P0175 | Electronic fuel mixture control | Excessive enrichment in row B |
P0181 | Fuel rail temperature sensor | Invalid temperature signal |
P0182 | Fuel rail temperature sensor | Low signal level at the circuit input |
P0183 | Fuel rail temperature sensor | High level signal at the input of the circuit |
P0191 | Fuel rail pressure sensor | Range/Characteristic |
P0192 | Fuel rail pressure sensor | Low input level |
P0193 | Fuel rail pressure sensor | High input level |
P0196 | Oil temperature sensor | Range/Characteristic |
P0197 | Oil temperature sensor | Low input level |
P0198 | Oil temperature sensor | High input level |
P0201 | Injector circuit | Malfunction in cylinder 1 |
P0202 | Injector circuit | Malfunction in cylinder 2 |
P0203 | Injector circuit | Malfunction in cylinder 3 |
P0204 | Injector circuit | Malfunction in cylinder 4 |
P0205 | Injector circuit | Malfunction in cylinder 5 |
P0206 | Injector circuit | Malfunction in cylinder 6 |
P0207 | Injector circuit | Malfunction in cylinder 7 |
P0208 | Injector circuit | Malfunction in cylinder 8 |
P0222 | APP sensor (accelerator pedal position) 2 | Low input level |
P0223 | APP sensor (accelerator pedal position) 2 | High input level |
P0227 | APP sensor (accelerator pedal position) 1 | Low input level |
P0228 | APP sensor (accelerator pedal position) 1 | High input level |
P0229 | APP sensor (accelerator pedal position) | Intermittent malfunction |
P0297 | Active speed control | Exceeding the normal vehicle speed |
P0300 | Misfire | Random misfire/series of misfires |
P0301 | Misfire | Cylinder 1 |
P0302 | Misfire | Cylinder 2 |
P0303 | Misfire | Cylinder 3 |
P0304 | Misfire | Cylinder 4 |
P0305 | Misfire | Cylinder 5 |
P0306 | Misfire | Cylinder 6 |
P0307 | Misfire | Cylinder 7 |
P0308 | Misfire | Cylinder 8 |
P0313 | Misfire | Misfire at low fuel level |
P0316 | Misfire | Misfire detected in the first 1000 rpm |
P0326 | Knock sensor | Wrong sensor characteristic 1 |
P0327 | Knock sensor | Row A Sensor Input Low |
P0328 | Knock sensor | High signal level at the input of the row A sensor |
P0331 | Knock sensor | Wrong sensor characteristic 2 |
P0332 | Knock sensor | Row B Sensor Input Low |
P0333 | Knock sensor | High signal level at the input of the row A sensor |
P0335 | Engine start sensor | Malfunction in a chain of the gauge at start/during operation |
P0336 | Engine start sensor | Range/Characteristic |
P0340 | CMP sensor (camshaft position) at inlet bank A | Crash at startup/during operation |
P0341 | CMP sensor (camshaft position) at inlet bank A | Range/Characteristic |
P0345 | CMP sensor (camshaft position) at B bank intake | Crash at startup/during operation |
P0346 | CMP sensor (camshaft position) at B bank intake | Range/Characteristic |
P0351 | Ignition coil | Malfunction in a chain of cylinder 1 |
P0352 | Ignition coil | Malfunction in a chain of the cylinder 2 |
P0353 | Ignition coil | Malfunction in a chain of the cylinder 3 |
P0354 | Ignition coil | Malfunction in a chain of the cylinder 4 |
P0355 | Ignition coil | Malfunction in a chain of the cylinder 5 |
P0356 | Ignition coil | Malfunction in a chain of the cylinder 6 |
P0357 | Ignition coil | Malfunction in a chain of the cylinder 7 |
P0358 | Ignition coil | Malfunction in a chain of the cylinder 8 |
P0365 | CMP sensor (camshaft position) on row A outlet | Crash at startup/during operation |
P0366 | CMP sensor (camshaft position) on row A outlet | Range/Characteristic |
P0390 | CMP sensor (camshaft position) on row B outlet | Crash at startup/during operation |
P0391 | CMP sensor (camshaft position) on row B outlet | Range/Characteristic |
P0401 | EGR system (exhaust gas recirculation) | Registration of insufficient flow |
P0403 | EGR system (exhaust gas recirculation) | Valve circuit input low/high |
P0405 | Differential pressure sensor | Short circuit to ground |
P0406 | Differential pressure sensor | Short circuit to battery |
P0409 | Differential pressure sensor | Characteristic |
P0420 | Bank A catalytic converter | Efficiency below threshold |
P0430 | catalytic converter | Efficiency below threshold |
P0441 | Purge valve | Characteristic |
P0442 | DMTL | Moderate leak detection |
P0447 | DMTL | Short circuit to ground |
P0448 | DMTL | Short circuit to battery |
P0455 | DMTL | Large leak detection |
P0456 | DMTL | Weak leak detection |
P0458 | Purge valve | Short circuit to ground |
P0459 | Purge valve | Short circuit to battery |
P0461 | Fuel level sensor | Range/Characteristic |
P0480 | Radiator fan assembly | Malfunction in the control circuit |
P0493 | Viscous fan | Speed out of range |
P0501 | Vehicle speed | Range/Characteristic Fault |
P0504 | brake switch | Circuit fault |
P0506 | Idle speed control system | RPM lower than expected |
P0507 | Idle speed control system | RPM higher than expected |
P0512 | Crank request circuit | High/Low Input Level |
P0513 | security system key | Invalid key |
P0532 | Air conditioning refrigerant pressure sensor | Low input level |
P0533 | Air conditioning refrigerant pressure sensor | High input level |
P0560 | Backup battery | Malfunction |
P0562 | Sensor power | Low input level |
P0563 | Sensor power | High input level |
P0566 | Speed control override switch | Malfunction in the on position |
P0567 | Speed control resume switch | Malfunction in the on position |
P0568 | Cruise control | Low/high input level |
P0569 | Speed reset/learn/set switch | Malfunction in the on position |
P0570 | Speed dial/memory/set switch | Malfunction in the on position |
P0574 | Cruise control | Speed control |
P0576 | Cruise control | Low input level |
P0577 | Cruise control | High input level |
P0604 | ECM self-diagnosis (the engine control unit) | RAM error |
P0605 | ECM self-diagnosis (the engine control unit) | ROM error |
P0606 | ECM self-diagnosis (the engine control unit) | Processor error |
P0616 | Starter relay | Low input level |
P0617 | Starter relay | High input level |
P0627 | Main fuel pump | Lack of teams |
P0628 | Fuel pump | Low electrical signal |
P0629 | Fuel pump | High electrical signal |
P0633 | Protection | No ID in ECM (the engine control unit) |
P0634 | ECM temperature (the engine control unit) | Too high internal temperature |
P0646 | Air conditioning compressor clutch relay | Low input level |
P0647 | Air conditioning compressor clutch relay | High input level |
P0661 | Manifold valve actuator output 1 | Open or short circuit in the circuit |
P0662 | Manifold valve actuator output 1 | Short circuit to battery |
P0664 | Manifold valve actuator output 2 | Open or short circuit in the circuit |
P0665 | Manifold valve actuator output 2 | Short circuit to battery |
P0668 | ECM temperature sensor (the engine control unit) | Short circuit to ground |
P0669 | ECM temperature sensor (the engine control unit) | Short circuit to battery |
P0687 | EMS control relay | Relay failure |
P0831 | Clutch switch circuit A | Low input level |
P0832 | Clutch switch circuit A | High input level |
P0834 | Clutch Switch Circuit B | Low input level |
P0835 | Clutch Switch Circuit B | High input level |
P0851 | Park/neutral position sensor | Low signal level at the circuit input |
P0852 | Park/neutral position sensor | High level signal at the input of the circuit |
P1136 | Control junction box fan | Fan failure |
P1146 | Generator control circuit | Low input signal/transmission error |
P1155 | HEGO heater row A | |
P1160 | UHEGO series A | slow response |
P1197 | UHEGO series A | Slow trip/open/short circuit |
P1198 | UHEGO Series B | Slow trip/open/short circuit |
P1233 | Auxiliary fuel pump | Break in the output circuit |
P1234 | Main fuel pump | Lack of teams |
P1236 | Main fuel pump | The pump does not turn on when a command is received |
P1244 | Generator control circuit | High input level |
P1260 | Activation of the security system | Attempted hijacking |
P1339 | Auxiliary fuel pump | Drive circuit output low/high |
P1367 | Bank A ignition coil | |
P1368 | Bank A ignition coil | |
P1452 | DMTL | Reference current too low |
P1453 | DMTL | Reference current too strong |
P1482 | DMTL heater control circuit | Low signal |
P1483 | DMTL heater control circuit | High signal level |
P1582 | flight recorder | Saving data |
P1624 | Security system ID | Failed to pass ID |
P1629 | Generator | Fault in the FR circuit |
P1632 | Generator | Malfunction in the charging system |
P1646 | UHEGO row A sensor | Slow response / open / short circuit in the control unit |
P1647 | UHEGO row B sensor | Slow response / open / short circuit in the control unit |
P1670 | Control junction box fan | Unacceptably low signal level |
P1671 | Control junction box fan | Unacceptably high signal level |
P1697 | Cruise control | Malfunction in the on state of the increase / decrease switch |
P1700 | Low gear ratio | Plausibility check |
P2066 | Auxiliary fuel pump | Range check |
P2070 | Manifold valve actuator output 1 | Stuck Open/Closed During Function Test |
P2071 | Manifold valve actuator output 2 | Stuck Open/Closed During Function Test |
P2101 | Electronic throttle | Characteristic |
P2103 | Electronic throttle | Continuous throttle |
P2105 | Electronic throttle | MIL double fuel cut request (malfunction indicator lamp) |
P2106 | Intentionally reduced utilization rate | Failed to change configuration |
P2118 | Electronic Throttle Control System | Overcurrent detection in hardware |
P2119 | Electronic throttle | Throttle stuck open |
P2122 | APP sensor (accelerator pedal position) | Circuit 2 input low |
P2123 | APP sensor | Circuit 2 input high |
P2228 | HAC sensor | Circuit Low |
P2229 | HAC sensor | High signal level in the circuit |
P2299 | Accelerator pedal | Brake lock |
P2401 | DMTL pump | Short circuit to ground |
P2402 | DMTL pump | Short circuit to battery |
P2404 | DMTL pump | Noise/reference leakage |
P2450 | DMTL | COV stuck open |
P2451 | DMTL | COV stuck closed |
P2503 | Charging system | Low voltage |
P2504 | Charging system | High voltage |
P2601 | coolant pump | Characteristic |
P2610 | Engine off timer | Timer failure |
P2632 | Auxiliary fuel pump drive circuit | Break in the output circuit |
P2633 | Auxiliary fuel pump drive circuit | Low output level |
P2634 | Auxiliary fuel pump drive circuit | High input level |
P6365 | Main fuel pump | The pump does not turn on when a command is received |
P2636 | Auxiliary fuel pump | Low consumption/performance |
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