ECM (Engine Control Unit) Correction 4.0L (Discovery 3)

ECM Correction (engine control unit)

ECM (engine control unit) has a function for correcting parameters that affect the nature of the control signal. This function enables the engine management system (EMS) to maintain exhaust gas toxicity within the established standards and optimize engine operation in the field of multi-parameter characteristics.

The components for which parameter correction can be performed 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-defined fuel management strategy (engine control unit), includes short-term correction and long-term collection. ECM (engine control unit) monitors the HO2S characteristic during its operation. In addition, the ECM monitors the current corrections made to these sensors.

The original text can be found at [LRMAN.ru]

In cases where the correction parameters go beyond the permissible values, the ECM (engine control unit) stores the fault code. At the same time, the ECM (engine control unit) records the crankshaft speed, engine load and intake air temperature.

CKP sensor (crankshaft position)

CKP Sensor Signal Characteristics (crankshaft position) are stored by the ECM unit (engine control unit). This allows the ECM (engine control unit) calculate correction parameters and support the cylinder misfire detection function. Since all flywheels and CKP sensors (crankshaft position) are slightly different from each other, then when replacing (or when removing and installing) any of the named components, the correction parameters must be updated. The correction parameters must also be updated when the ECM is replaced. (engine control unit). ECM (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 rotation speed. The ranges of crankshaft rotation speeds are characterized in the table:

Correction	Crankshaft speed, rpm
1	1800 - 3000
2	3001 - 3800
3	3801 - 4600
4	4601 - 5400

Missed Flash Detection

Legislation requires that ECM (engine control unit) could detect misfires in the cylinders. The ECM must distinguish between two types (levels) of misfires. The first type of misfire is one that results in an increase in the total emission of toxic substances by 1.5 times when determining their concentration in accordance with the Federal FTP method. The second type of misfire can lead to damage to the catalytic converter.

ECM (engine control unit) monitors the number of misfire occurrences in two specified speed ranges. If the number of detected ECMs (engine control unit) if the number of flashes missed in any of the speed ranges exceeds a preset value over two consecutive trips, the ECM (engine control unit) will record the fault code and related parameters: crankshaft speed, engine load and coolant temperature. In addition, the ECM (engine control unit) monitors the number of misfires per 200 crankshaft revolutions. These misfires are assessed for their potential to cause damage to the catalytic converters. If the number of misfires exceeds a certain value, the ECM (engine control unit) will record the neutralizer threat status code and related parameters: crankshaft speed, engine load and coolant temperature.



The shape of the crankshaft position sensor signal depends on the speed of the flywheel relative to the sensor tip. Each time a tooth of the timing gear passes the sensor tip, a sinusoidal signal is formed in the latter. ECM (engine control unit) determines the change in flywheel rotation speed (crankshaft) by changing the shape of the sinusoidal signal coming from the sensor.

Analysis of the received signal allows ECM (engine control unit) detect the fact of a missed flash. At this point in time, the ECM (engine control unit) evaluates the degree of change in the crankshaft position sensor signal and assigns a ripple factor to it. The ripple factor value can be monitored in real time using the T4. ECM (engine control unit) analyzes the signal by several parameters and makes a decision on whether to count the event or not. ECM (engine control unit) can establish the fact of misfiring and assign a coefficient of unevenness in relation to each individual cylinder.

Diagnostics using the T4 device

ECM (engine control unit) stores fault data as DTCs (diagnostic trouble codes), referred to as 'P' codes. 'P' codes are defined by OBD regulations (on-board self-diagnostic system) and along with their associated environmental conditions and freeze frame data can be read out via a third-party diagnostic tool or the T4. The T4 is also capable of reading out sensor data, the currently used parameter settings, and the current fuel, ignition and idle speed parameters in real time.

Code number P	Component/signal	Description of the malfunction
P0011	CMP (camshaft position) /CKP (crankshaft position) /VVT	Position Error, VVT Retard Position Signal High for CMP (camshaft position) /CKP (crankshaft position) row A
P0012	CMP (camshaft position) /CKP (crankshaft position) /VVT	Position Error, VVT Retard Position Signal Low for CMP (camshaft position) /CKP (crankshaft position) row A
P0021	CMP (camshaft position) /CKP (crankshaft position) /VVT	Position Error, VVT Retard Position Signal High for CMP (camshaft position) /CKP (crankshaft position) row B
P0022	CMP (camshaft position) /CKP (crankshaft position) /VVT	Position Error, VVT Retard Position Signal Low for CMP (camshaft position) /CKP (crankshaft position) row B
P0026	VVT	Low/High Bank A Circuit Malfunction Signal
P0028	VVT	Low/High Bank B Circuit Malfunction Signal
P0031	UHEGO	Low Signal Level in the Control Circuit of the Heater Row A
P0032	UHEGO	Row A Heater Control Circuit High
P0051	UHEGO	Low Signal Level in the Control Circuit of the B-Bank Heater
P0052	UHEGO	Row B Heater Control Circuit High
P0069	HAC	Sensor characteristic/circuit
P0071	Outside air temperature sensor	Characteristic
P0072	Outside air temperature sensor	Low signal level at the input of the circuit
P0073	Outside air temperature sensor	High signal level at the input of the circuit
P0075	VVT	Open circuit in row A
P0076	VVT	Short circuit to ground in the A-row circuit
P0077	VVT	Short circuit to battery in row A circuit
P0081	VVT	Open circuit in row B
P0082	VVT	Short circuit to ground in the B-row circuit
P0083	VVT	Short circuit to battery in row B circuit
P0087	Fuel system	Minor malfunction
P0088	Fuel system	Major malfunction
P0089	Fuel system	Interference
P0093	Fuel system	Major leak
P0096	IAT (intake air temperature)	Sensor characteristics
P0101	AFM	Chain characteristics
P102	AFM	Low signal level at the input of the circuit
P103	AFM	High signal level at the input of the circuit
P0106	MAP (manifold absolute pressure)	Sensor characteristics
P0107	MAP (manifold absolute pressure)	Low signal level at the input of the circuit
P0108	MAP (manifold absolute pressure)	High signal level 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 input of the circuit
P0118	ECT (coolant temperature)	High signal level at the input of the circuit
P0121	Throttle body circuits 1 and 2	Range/Characteristic
P0122	Throttle Valve Circuit 1	Low input signal level
P0123	Throttle Valve Circuit 1	High input signal level
P0125	ECT (coolant temperature)	Insufficient coolant temperature for closed loop control system
P0128	Thermostat control circuit	Low coolant temperature - thermostat stuck open
P0131	UHEGO	Short circuit to ground in the A-row circuit
P0132	UHEGO	Short circuit to battery in row A circuit
P0133	UHEGO	Slow reaction for series A
P0136	HEGO	Setting parameters for row A
P0137	HEGO	Short circuit to ground in the A-row circuit
P0138	HEGO	Short circuit to battery in row A circuit
P0139	HEGO	Slow reaction for series A
P0140	HEGO	No signals for row A
P0141	HEGO	Malfunction in the control circuit of the heater row A
P0150-1A	HEGO	Low impedance of row A element
P0151	UHEGO	Short circuit to ground in the B-row circuit
P0152	UHEGO	Short circuit to battery in row B circuit
P0153	UHEGO	Slow reaction for row B
P0154-00	UHEGO	Slow response for row B
P0156	HEGO	Setting parameters for row B
P0157	HEGO	Short circuit to ground in the B-row circuit
P0158	HEGO	Short circuit to battery in row B circuit
P0159	HEGO	Slow reaction for row B
P0160	HEGO	No signals for row B
P0161	HEGO	Malfunction in the control circuit of the heater of the bank B
P00171	Electronic fuel mixture control	Excessive lean in row A
P0172	Electronic fuel mixture control	Over-enrichment in series A
P0174	Electronic fuel mixture control	Excessive lean in row B
P0175	Electronic fuel mixture control	Over-enrichment in series B
P0181	Fuel Rail Temperature Sensor	Invalid temperature signal
P0182	Fuel Rail Temperature Sensor	Low signal level at the input of the circuit
P0183	Fuel Rail Temperature Sensor	High signal level at the input of the circuit
P0191	Fuel Rail Pressure Sensor	Range/Characteristic
P0192	Fuel Rail Pressure Sensor	Low input signal level
P0193	Fuel Rail Pressure Sensor	High input signal level
P0196	Oil temperature sensor	Range/Characteristic
P0197	Oil temperature sensor	Low input signal level
P0198	Oil temperature sensor	High input signal level
P0201	Injector chain	Cylinder 1 fault
P0202	Injector chain	Cylinder 2 fault
P0203	Injector chain	Cylinder 3 fault
P0204	Injector chain	Cylinder 4 fault
P0205	Injector chain	Cylinder 5 fault
P0206	Injector chain	Cylinder 6 fault
P0207	Injector chain	Cylinder 7 fault
P0208	Injector chain	Cylinder 8 fault
P0222	APP sensor (accelerator pedal position) 2	Low input signal level
P0223	APP sensor (accelerator pedal position) 2	High input signal level
P0227	APP sensor (accelerator pedal position) 1	Low input signal level
P0228	APP sensor (accelerator pedal position) 1	High input signal level
P0229	APP sensor (accelerator pedal position)	Intermittent malfunction
P0297	Active Speed Control	Exceeding the normal speed of the vehicle
P0300	Misfire	Random misfire/misfire series
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 with low fuel level
P0316	Misfire	Misfire detected in first 1000 rpm
P0326	Knock sensor	Incorrect sensor characteristic 1
P0327	Knock sensor	Low signal level at the input of the sensor of the row A
P0328	Knock sensor	High level signal at the input of the sensor of row A
P0331	Knock sensor	Incorrect sensor characteristic 2
P0332	Knock sensor	Low signal level at the input of the sensor of the row B
P0333	Knock sensor	High level signal at the input of the sensor of row A
P0335	Engine start sensor	Sensor circuit fault at start-up/during operation
P0336	Engine start sensor	Range/Characteristic
P0340	CMP sensor (camshaft position) at the inlet of row A	Crash on startup/during operation
P0341	CMP sensor (camshaft position) at the inlet of row A	Range/Characteristic
P0345	CMP sensor (camshaft position) at the inlet of row B	Crash on startup/during operation
P0346	CMP sensor (camshaft position) at the inlet of row B	Range/Characteristic
P0351	Ignition coil	Malfunction in cylinder 1 circuit
P0352	Ignition coil	Malfunction in the cylinder 2 circuit
P0353	Ignition coil	Malfunction in the cylinder 3 circuit
P0354	Ignition coil	Malfunction in the cylinder 4 circuit
P0355	Ignition coil	Malfunction in the cylinder 5 circuit
P0356	Ignition coil	Malfunction in the cylinder 6 circuit
P0357	Ignition coil	Malfunction in the cylinder 7 circuit
P0358	Ignition coil	Malfunction in the cylinder 8 circuit
P0365	CMP sensor (camshaft position) on the release of row A	Crash on startup/during operation
P0366	CMP sensor (camshaft position) on the release of row A	Range/Characteristic
P0390	CMP sensor (camshaft position) on the release of row B	Crash on startup/during operation
P0391	CMP sensor (camshaft position) on the release of row B	Range/Characteristic
P0401	EGR system (exhaust gas recirculation)	Registration of insufficient consumption
P0403	EGR system (exhaust gas recirculation)	Low/High Input Signal Level of Valve Circuit
P0405	Differential pressure sensor	Short circuit to ground
P0406	Differential pressure sensor	Short circuit to battery
P0409	Differential pressure sensor	Characteristic
P0420	Catalytic converter row A	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	Detecting a major leak
P0456	DMTL	Detecting a weak leak
P0458	Purge valve	Short circuit to ground
P0459	Purge valve	Short circuit to battery
P0461	Fuel level sensor	Range/Characteristic
P0480	Radiator Fan Block	Control circuit fault
P0493	Viscous coupling fan	Speed out of range
P0501	Car speed	Range/performance related fault
P0504	Brake switch	Circuit fault
P0506	Idle Speed Control System	RPM is lower than expected
P0507	Idle Speed Control System	The rotation speed is higher than expected
P0512	Crankshaft rotation request circuit	High/low input signal level
P0513	Security system key	Invalid key
P0532	Air conditioning refrigerant pressure sensor	Low input signal level
P0533	Air conditioning refrigerant pressure sensor	High input signal level
P0560	Backup battery	Malfunction
P0562	Sensor power supply	Low input signal level
P0563	Sensor power supply	High input signal 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 signal level
P0569	Speed reset/memory/setup switch	Malfunction in the on position
P0570	Speed dial/memory/setup switch	Malfunction in the on position
P0574	Cruise control	Speed control
P0576	Cruise control	Low input signal level
P0577	Cruise control	High input signal level
P0604	ECM self-diagnosis (engine control unit)	RAM error
P0605	ECM self-diagnosis (engine control unit)	ROM error
P0606	ECM self-diagnosis (engine control unit)	CPU error
P0616	Starter relay	Low input signal level
P0617	Starter relay	High input signal level
P0627	Main fuel pump	Lack of commands
P0628	Fuel pump	Low electrical signal level
P0629	Fuel pump	High electrical signal level
P0633	Protection	Missing ID in ECM (engine control unit)
P0634	ECM Temperature (engine control unit)	Internal temperature too high
P0646	Air Conditioning Compressor Clutch Relay	Low input signal level
P0647	Air Conditioning Compressor Clutch Relay	High input signal level
P0661	Manifold Valve Drive Output 1	Open or short circuit in the circuit
P0662	Manifold Valve Drive Output 1	Short circuit to battery
P0664	Manifold Valve Drive Output 2	Open or short circuit in the circuit
P0665	Manifold Valve Drive Output 2	Short circuit to battery
P0668	ECM Temperature Sensor (engine control unit)	Short circuit to ground
P0669	ECM Temperature Sensor (engine control unit)	Short circuit to battery
P0687	EMS control relay	Relay failure
P0831	Clutch Switch Chain A	Low input signal level
P0832	Clutch Switch Chain A	High input signal level
P0834	Clutch Switch Circuit B	Low input signal level
P0835	Clutch Switch Circuit B	High input signal level
P0851	Parking/Neutral Position Sensor	Low signal level at the input of the circuit
P0852	Parking/Neutral Position Sensor	High signal level at the input of the circuit
P1136	Fan of the control system mounting box	Fan malfunction
P1146	Generator control circuit	Low Input Signal/Data Transfer Error
P1155	HEGO heater series A
P1160	UHEGO series A	Slow response
P1197	UHEGO series A	Slow response/open/short circuit
P1198	UHEGO B-series	Slow response/open/short circuit
P1233	Auxiliary fuel pump	Open circuit in output circuit
P1234	Main fuel pump	Lack of commands
P1236	Main fuel pump	The pump does not turn on when the command is received
P1244	Generator control circuit	High input signal level
P1260	Turning on the security system	Attempted theft
P1339	Auxiliary fuel pump	Low/High Level of Signal at the Output of the Drive Circuit
P1367	Ignition coil row A
P1368	Ignition coil row A
P1452	DMTL	Too weak reference current
P1453	DMTL	Too high reference current
P1482	DMTL Heater Control Circuit	Low signal level
P1483	DMTL Heater Control Circuit	High signal level
P1582	Flight recorder	Saving data
P1624	Security system identifier	Error in ID transfer process
P1629	Generator	Malfunction in FR circuit
P1632	Generator	Malfunction in the charging system
P1646	UHEGO sensor row A	Slow response/open/short circuit in control unit
P1647	UHEGO sensor row B	Slow response/open/short circuit in control unit
P1670	Fan of the control system mounting box	Unacceptably low signal level
P1671	Fan of the control system mounting box	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 Drive Output 1	Jamming in open/closed position during operability check
P2071	Manifold Valve Drive Output 2	Jamming in open/closed position during operability check
P2101	Electronic throttle	Characteristic
P2103	Electronic throttle	Continuous throttle operation
P2105	Electronic throttle	Dual Fuel Cut MIL Request (malfunction indicator lamp)
P2106	Intentionally reduced utilization rate	Crash while changing configuration
P2118	Electronic throttle control system	Hardware overcurrent detection
P2119	Electronic throttle	Throttle valve stuck open
P2122	APP sensor (accelerator pedal position)	Low signal level at the input of circuit 2
P2123	APP sensor	High signal level at input of circuit 2
P2228	HAC sensor	Low signal level in the circuit
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	Interference/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 Shutdown Timer	Timer malfunction
P2632	Auxiliary fuel pump drive chain	Open circuit in output circuit
P2633	Auxiliary fuel pump drive chain	Low signal level at the output
P2634	Auxiliary fuel pump drive chain	High input signal level
P6365	Main fuel pump	The pump does not turn on when the command is received
P2636	Auxiliary fuel pump	Low consumption/performance