ECU replacement

[Drakman]

Hi Guys and Girls,

 

I have a 2014 Roadsport 175 that has an alloy "lotus" branded ECU.  I believe these are a locked unit and can't be adjusted.

I am looking to replace the lotus ECU with a Haltech Elite 1500 as a first step in some modifications to the engine.  I have to admit I don't know much about the electronic side of the car, I thought I could just unplug the Lotus ECU and plug the new one in, apparently that isn't the case.  I have to either rewire the whole dash or cut the plugs off the Lotus ECU and find a "pinout" to rewire the Haltech in it's place.  Is this normally what is done or is there an ECU that does just plug and play for the Caterham?

 

Cheers

Dave

[aerobod - near CYYC]

Hi Dave, a number of options :

1. Cut off the existing connector(s) and rewire to the new ECU - potentially difficult to do if the amount of wire and wrapping of the loom prevents enough free cable to put the new connector(s) on. Not a task for the in-experienced, especially producing quality crimps with the new pins on relatively short cable ends, even with the right crimping tool.

2. Build or have built an adapter - requires identification of the existing connector(s) and an adapter cable to be built that converts the existing loom connector(s) to the new ECU.

3. Identify the existing Caterham ECU and buy an unlocked version - This is generally possible if it is an MBE ECU, with SBD Motorsports being the main source of unlocked ECUs with a base starting map. This also requires the right tuning software (Easimap for MBE ECUs), adapter cable and laptop.

4. Find a Caterham tuning specialist that has the ability to unlock the ECU and re-tune it for you - If you search this site, you will find others who have done this in the past.

In any case the existing ECU needs to be identified and a pin-out for the connector(s) obtained, as even a plug-compatible ECU may have sensor pin-out differences configured compared with the existing ECU, so all sensor pin mappings need to be understood.

The Caterham ECUs available can be compared here (https://caterhamparts.co.uk/search?controller=search&orderby=position&orderway=desc&search_query=Ecu&submit_search=&p=2) to try to identify the existing unit, as a starting point to find an equivalent unlocked one.

[aerobod - near CYYC]

With you being Australia, you may be able to have a UK company do remote tuning for you, I know SBD do this for MBE ECUs, but other organizations can too. You would need to have the car on a rolling road and appropriate software and laptop hooked up, they then do a remote session to build a new map while you or the rolling road operator control the car to their instructions.

In my case being in Canada, I swapped the ECU for an unlocked plug compatible version on my 2012 R400D, got a base starting map, changed it from MAP mapping to Alpha-N with appropriate sensor and wiring to the ECU changed, then tuned it on the road myself by logging all parameters over a wide operating range, analyzing the logged results, then adjusting the fueling, followed by iterating the logging again until I got the maps just right.

[Jonathan Kay]

I have a collection of wiring diagrams, including some for Sigma-engined Sevens that never appeared in Assembly Guides. Please send me a Private Message with your email address if you'd like copies.

Jonathan

[Jonathan Kay]

Please could you add some photos of the current ECU and connectors.

Thanks

Jonathan

[simon_h]

The ECU in question is a Lotus T6 ecu. The pin out is similar but slightly different to a Lotus Evora. There wont be anyone who has bothered to hack the unique Caterham code in this unit I am fairly sure. The dash will stop working as the ecu drives the dials via CAN and they suit the ecu's CAN database not a general one.

Best bet is to do one of the following;

Cut off the plugs and fit your own plugs to what ever ecu you please.

Cut up the ecu, or find a scrap one, remove the header connector and make an adapter loom to your choice of ecu.

Get a plug compatible EFI Euro8 ecu but you will need to re-pin the connectors as it is a slightly different pin out.

Contact SCS in the UK who make a plug compatible replacement unit for the Lotus versions and ask them if they will write you some code to run a Ford Duratec in that unit.

Remove everything and fit a UK spec cable throttle wiring loom, MBE ecu, cable throttle body and pedal. Probably the easiest route all said.

[Drakman]

Wow, thanks Guys, I had no idea what I was getting myself into here.  Lots of great info.  Jonathan, I will send some photos and hopefully you may have something that shows what i need, thank you.

 

Cheers

Dave

[Drakman]

Hello again,

 

Here are some photos of the ECU I want to find a replacement for.  If there is no simple plug and play ECU available it shouldn't matter what brand of ECU I get, should it?  The Haltech is a common ECU here in Australia or is there an ECU better suited to the Caterham Duratech engine?

Cheers

Dave

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