ECM AFM1040, Instruction Manual

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Command Mode
Command Mode is used to auto-detect AFM1540 and F/A1540 modules on the SMB bus.
After the reception of command XXXX 0000 (where XXXX = module address) the module
switches into Command Mode and waits for a second byte. Upon entering Command Mode,
wait 30 ms minimum before issuing commands.
The sensor is powered off when the unit
is in Command Mode.
The module remains waiting until a second byte with the correct
device number in the high-nibble is received.
1st BYTE 2nd BYTE COMMAND NO. COMMAND
XXXX 0000 XXXX 0000 0 Stay in Command Mode
XXXX 0000 XXXX 0001 1 Device Identification (See Below)
XXXX 0000 XXXX 0010 2 Not Used
…. …. …. ….
XXXX 0000 XXXX 1111 15 Exit Command Mode
Device Identification
In response to the DEVICE IDENTIFICATION command, the module sends back 6 bytes
(including a check sum): 0x00, 0x02, 0x18, 0x0C, 0x00, 0xDA. This will identify the
module as an ETAS LA3 to INCA software.
Calibration
Calibration of the AFM and the lambda sensor can be easily performed using air.
To bring the system into calibration, put the sensor in air and adjust the calibration
potentiometer (CAL POT) on the control module using the calibration screwdriver provided.
First turn the potentiometer counter-clockwise until the CAL LED (yellow) is off, then turn
the potentiometer slowly clockwise until the CAL LED just lights. If the CAL POT cannot
be turned to where the CAL LED is off then the sensor is bad.
For best accuracy, the AFM and lambda sensor should be on for at least 20 minutes prior to
calibration.
For best accuracy, the lambda sensor should be held with its tip pointing down in still air
during calibration. Calibrating with the sensor in an “off ” engine is not recommended due to
the possibility of residual exhaust gases remaining in the exhaust system.
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