ENGINE MANAGEMENT SYSTEM - V8
Function
With the ECM operating in the 'New' state, TestBook is required to instruct the ECM to learn the new BCU code. If the
ECM is in delivery state (i.e. direct from the supplier), it will not run the vehicle and will store a new ECM fault code
when it is fitted. This code must be cleared after instructing the ECM to learn the BCU code using TestBook.
When the ECM is in the 'Secure' state, no further action is required as the ECM has successfully learned the BCU
code. A 'Secure' ECM can not be configured to a 'No Code' state.
If the vehicle is fitted with an ECM with a valid code, the engine will start and the MIL will go out.
However, if the ECM has an invalid BCU security code the engine will crank, start, and then immediately stall. The
status of the security system can only be interrogated using TestBook.
TestBook is able to retrieve the following immobilisation fault codes:
P Code
P1666
P1667
P1668
P1672
J2012 Description
Engine anti-theft signal circuit malfunction
Engine anti-theft signal circuit low
Engine anti-theft signal circuit high
Land Rover Description
BCU serial link frame/ bit timing error
Serial link short circuit to earth
Serial link open circuit
Engine anti-theft signal circuit wrong code
received
Secure ECM, received incorrect code
P1673
P1674
Engine anti-theft signal new engine control
module not configured
New ECM fitted
Engine anti-theft signal
No code ECM, valid code received
Misfire detection
Due to increasing legislation, all new vehicles must be able to detect two specific levels of misfire.
Conditions
The ECM is able to carry out misfire detection as part of the OBD system using the following component parts:
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Flywheel reluctor adaptation.
Calculation of engine roughness.
Detection of excess emissions misfire.
Detection of catalyst damaging misfire.
Function
The flywheel/ reluctor ring is divided into four segments 90° wide. The ECM misfire detection system uses information
generated by the CKP to determine crankshaft speed and position. If a misfire occurs, there will be an instantaneous
slight decrease in engine speed. The ECM misfire detection system is able to compare the length of time each 90°
segment takes and is therefore able to pinpoint the source of the misfire.
For the ECM misfire detection system to be calibrated for the tolerances of the reluctor tooth positions, the flywheel/
reluctor ring must be 'adapted' as follows:
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1800 - 3000 rev/min = speed range 1.
3000 - 3800 rev/min = speed range 2.
3800 - 4600 rev/min = speed range 3.
4600 - 5400 rev/min = speed range 4.
The ECM carries out flywheel/ reluctor ring adaptions across all the above speed ranges and can be monitored by
TestBook. The test should be carried out as follows:
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Engine at normal operating temperature.
Select second gear (for both automatic and manual transmission vehicles).
Accelerate until engine rev limiter is operational.
Release throttle smoothly to allow engine to decelerate throughout the speed ranges.
Repeat process as necessary until all adaptations are complete.
DESCRIPTION AND OPERATION 18-2-53
| Categories | Land Rover Defender, Land Rover Discovery II, Range Rover |
|---|---|
| Tags | Land Rover |
| Model Year | 1999 |
| Download File |
|
| Document Type | Workshop Manual |
| Language | English |
| Product Name | Discovery Series II |
| Product Brand | Land Rover |
| Document File Type | |
| Publisher | landrover.com |
| Wikipedia's Page | http://en.wikipedia.org/wiki/Land_Rover |
| Copyright | Attribution Non-commercial |
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