Relays and Modules *** READ THIS FIRST ***

[swindon_alan]

Another labour of love complete!

This thread came about because of this post:

http://www.thelotusforums.com/forums/topic/81207-relay-window-voltage-module-c082m6531f-required/?do=findComment&comment=635553

I was curious about this part as I couldn't find any cross references whatsoever. It turns out that a few of the relay modules in the Stevens cars are unbelievably not parts bin sourced but were probably custom made for Lotus. Blimey! Of course, this will cause us failure replacement problems in the future as when the remaining stock (if still available) held by the likes of SJ and Elise Shop have gone then we will be stuffed.

So to find out what they actually do and how they work I took mine apart and reverse engineered these specials, coming up with workarounds (which I have tested and they all do the job). As is my wont, I then got my spade out and dug and dug and ended up carrying on and compiling lists and cross references for every relay/module for every Esprit made (!)

Attached is an Excel spreadsheet with two tabs, firstly description/part number against Esprit model and the second gives cross references, alternatives, current stockists (May 2016) and TLF forum links where appropriate.

Relays.xlsx

*** HELP REQUESTED ***
I pulled all of the relays in my V8 and read off the manufacturers/part numbers to get cross references against Lotus part numbers but I can't do that for the other models. If you have an earlier car and the time I would be grateful if you could do the same for me and post up or PM the details. I can then update the spreadsheet. The ones I am missing are noted in YELLOW in the spreadsheet, although any other equivalents of those I already have info on would be useful too. Thank you in advance.

Note that there are four relays which are pretty common in most Esprits that are industry standard and can be as cheap as chips (the prefixes may differ but I am reasonably certain that current ones will do the job):

*079M6141F - Standard changeover relay ISO Type B 12V 20/30A
*082M6058F - Standard twin make and break relay ISO Type B 12V 2 x 15A
*082M6182F - Standard double make and break relay ISO Type B 12V 2 x 15A
*082M6589F - Standard high current relay with heat sink

Details and sourcing in the spreadsheet.

NOTES ON THE STEVENS BMI MODULES

There are four types of what appear to be "specials" in the Stevens Esprits. They are identified with the wording "BMI MADE IN UK" moulded into the top surface. They will probably have a sticky label on one of the sides with the Lotus part number and a date code. Scratching around Google, I think I found the now defunct manufacturer, who were based in Bristol. I am happy to be corrected though:

About B.M.I. Electronics Limited
Company Status: dissolved
Company Number: 01288781
Company Age: 39 Years - Incorporated on 01 Dec 1976
Country of Registration: GB
Company Type: Private limited with Share Capital
Business Activity: Manufacture of telegraph and telephone apparatus and equipment
Latest Accounts: 31 Dec 1997
Next Accounts Due: 30 Sep 1999

https://companycheck.co.uk/company/01288781/BMI-ELECTRONICS-LIMITED/about

So it looks as though they went bust in the late '90s which would fit with the end of Esprit production, assuming that Lotus had bought enough stock in advance.

Modules:

Headlamp pod delay module (BMI 01208E), *082M6325F http://www.thelotusforums.com/forums/topic/82336-relay-headlamp-pod-delay-module-082m6325f/
Window logic module (BMI 01210E), *082M6531F http://www.thelotusforums.com/forums/topic/81207-relay-window-voltage-module-c082m6531f-required/
Rheostat module (BMI 01206E), *082M4847F http://www.thelotusforums.com/forums/topic/82335-relay-rheostat-module-082m4847f/
Low fuel warning delay module (BMI 01212E), *089M6330F http://www.thelotusforums.com/forums/topic/82337-relay-low-fuel-delay-module-089m6330f/

I'm planning on designing a single microprocessor based module to replace all of these (as a pilot development ahead of my V8 ECM). Will post updates on that as and when.

[ramjet]

Looks like good work Alan. Well done.