The engine management system has a built in diagnostics plug (Assembly Line Diagnostic Link – ALDL) which is mounted in the passenger footwell on both LHD and RHD cars.

Although the location varies slightly. It can be easily seen with the glove box lowered and should be clipped into a plastic housing.  This is a view of the plug and housing located on a LHD car.

Stored fault codes can be read by Bridging terminal A (Black wire) & terminal B (white wire) with the ignition off

The simplest way to do this is by using a short piece of wire or paper clip. Lotus also supply a bridging plug p/n T000T0909. Turn the ignition on and monitor the amber Check Engine Light on the instrument cluster. It should emit a series of flashes with a short pause between them.

1 flash followed by 2 flashes indicates code 12.  (no faults found). This will be repeated 3 times and then any stored fault codes will follow. Each will be repeated 3 times. After the last code is displayed code 12 will be displayed. Check any displayed codes against the list.

ElanScan

By using ElanScan. It is possible to see real time readings for the sensors using a laptop (running windows 95 or higher operating system).  and either purchasing or making your own ALDL interface cable

Download ElanScan A free program developed by the Mountain Chip manufacturer.If using a USB ALDL cable you will also need to download and install  the USB Drivers.

Once you have installed the software and connected the cable to the ALDL plug you can start logging and saving the information into a file. To see the kind of data available.You can download a typical log file taken from my  car earlier this year.

Car started from cold to operating temprature

Car taken on a small test drive