Lotus 2004 ELISE Service Notes page 418

Lotus Service Notes
WD.4 - TROUBLE CODES
All the time the ignition is switched on, the Sensing and Diagnostic Module (SDM) continuously monitors
the resistance of various parts of the SRS electrical circuit, and compares these values with pre-programmed
tolerance bands to enable it to recognise 'faults' in the system and light the airbag tell tale lamp in the instru-
ment cluster. If such a fault is detected, the SDM stores a 'Trouble Code' for that particular type of fault in its
memory.
i). Current (Present) Codes - Faults that are currently being detected. Current codes are stored in the SDM
Random Access Memory (RAM), which will be cleared if the vehicle battery is disconnected.
ii). History (Not present) Codes - All faults detected since the last time faults were cleared from the memory
using the Lotus Scan tool. History codes are stored in the SDM Electronically Erasable Programmable
Read Only Memory (EEPROM) and are not cleared if the battery is disconnected.
Vehicle crash data is also stored in coded form in the SDM and is not erasable. New SDMs are supplied
only against V.I.N. and on exchange with the old unit.
WD.5 - LOTUS SCAN TOOL
In order to provide for communication with the airbag SDM, engine management system ECU and anti-
lock brake system, a hand held electronic scanner 'Lotus Scan 2' (part number T000T1418F), may be plugged
into the Data Link Connector (see earlier)
Amongst the operations available using the 'Lotus Scan 2' tool are:
- Reading of Trouble Codes
- Clearing of Trouble Codes
- Reading live data
Operating instructions are provided with the tool.
Important Note
The power supply transformer is used for overnight charging of the printer, and also for powering the
Scan 2 tool during software downloading from a PC (personal computer). For the software download opera-
tion, the Scan tool requires a power supply from the mains via the transformer and an inverter. Two types of
inverter have been used; early kits used an adaptor lead to plug into the bottom end of the Scanner tool. Later
kits use an adaptor plug fitting into the top end of the scanner.
When charging the printer, it is most important that the inverter is NOT used, or damage to the
transformer may be caused. Incorrect connection is possible only with the early type adaptor lead, with which
extra care should be exercised.
1. Reading data from vehicle
Data Link Connector (DLC)
(front of passenger footwell)
Page 4
Section WD
Scan 2
Printer
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