sylvaman Posted December 14, 2019 Share Posted December 14, 2019 Hi Paul , If you don't get sorted on here, Which i'm sure you will , as this site never ceases to amaze with all the knowledge and friendly, helpful folk. Give George Pinder a ring at Tytherleigh Vehicle Electrics , based at Chard in Somerset . I am happy to come along with you if it helps , as i took my Elise there last year. Not sure how far this is from you in North Dorset . Good luck . Link to comment Share on other sites More sharing options...
Pauls SLR Posted December 14, 2019 Author Share Posted December 14, 2019 AndrewIve got 12v on pin 3 of the MFRU whether the ignition is on or off. I've checked continuity from here to pin 4 on the ECU (I'm EU2) and that is fine, so it looks like it is the ECU not grounding the relay to allow it to work. As a check I connected the spare MFRU I have a d that gives the same. Ive emailed Karl at Emerald regarding the ECU so I guess I need to wait for a response from him in the week. sylvaman, that's a really kind offer - I will see how Karl responds and go from there.Paul Link to comment Share on other sites More sharing options...
SM25T Posted December 15, 2019 Share Posted December 15, 2019 Does the ECU have a separate earth cable ... check it is connected to something clean and bright. Try a cable from the casing to an earth point to see if it makes a difference ? Link to comment Share on other sites More sharing options...
Pauls SLR Posted December 15, 2019 Author Share Posted December 15, 2019 I've checked the ECU earthing with multimeter and also run a cable direct from the ECU to battery earth and this doesn't help. I'm now convinced it is an issue with the ECU. I'm away from the car this morning but might open the ECU this afternoon and see whether there is a failed joint in there somewhere.Thank you all for the help and suggestions Link to comment Share on other sites More sharing options...
revilla Posted December 15, 2019 Share Posted December 15, 2019 I've not played a lot with the Emerald (so this may be completely wrong / irrelevant) but from memory I think a lot of the pins are configurable as to their function. It might be worth checking whether that pin is configured correctly in the software, just in case something has been inadvertently corrupted. Link to comment Share on other sites More sharing options...
revilla Posted December 15, 2019 Share Posted December 15, 2019 Just had a very quick peep at the Emerald K3 and M3DK manuals.In the M3DK manual, Pin 4 is described as "Main Relay Control" however in the K3 manual it is described as "Ignition Driver 3/Main Relay Control" and "Igntion driver 3 or main relay control output according to ECU configuration". Not sure which one you have but that pin may indeed be configurable. Link to comment Share on other sites More sharing options...
Pauls SLR Posted December 15, 2019 Author Share Posted December 15, 2019 Mine is MD3K.Just as a final aside, I have opened the ECU. No obvious signs of corrosion or issues, but just as a little test if I use an earthed wire touched on the solder joint on the back of the board corresponding to pin 4 the relay is activated and I can start the car and it runs. As soon as I remove the wire the engine stops. I am assuming this means an issue with the ECU so probably can't go any further until Karl gets back to me, hopefully in the week. Link to comment Share on other sites More sharing options...
revilla Posted December 15, 2019 Share Posted December 15, 2019 Good investigation and yes it does sound like an ECU problem (either hardware or configuration) doesn't it? It won't be the ECU earthing if everything runs fine when you hold the main relay in with a finger. Ignition coils and injectors are also ECU switched earths and draw a lot more current so they would play up long before a relay failed to close. Fingers crossed that Karl comes up with some answers for you quickly. I'll be interested to hear what it was when it's all sorted. Link to comment Share on other sites More sharing options...
Nickhughes Posted December 16, 2019 Share Posted December 16, 2019 You could try HVE Mobile on 01258 459241. He is used by the garages in Blandford to sort out electrical problems, but have to say was not too keen to work on my seven when I had an electrical glitch. Said he had got stuck in one once. Link to comment Share on other sites More sharing options...
Pauls SLR Posted December 18, 2019 Author Share Posted December 18, 2019 Just to draw a line under this for anyone interested or to potentially help anyone else with a similar issue I exchanged a couple of emails with Karl at Emerald and sent the ECU up to him. He found some minor corrosion on the board on the trace to pin 4 and has fixed this. It was actually below the 36 pin connector so wasn't really visible until he removed the connector which may be why I missed it. Appears perhaps some moisture has got in at some stage: and I thought I was a fair weather motorist! Great service - it was in and out of Emerald the same day. Now just need some decent weather over the Christmas period so I can get out in the car. Many thanks for all the guidance on this thread.Paul Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted December 18, 2019 Member Share Posted December 18, 2019 Thanks for the update. Good to know about that service from Emerald.Have fun.Jonathan Link to comment Share on other sites More sharing options...
revilla Posted December 18, 2019 Share Posted December 18, 2019 Excellent news Link to comment Share on other sites More sharing options...
Area Representative Golf Juliet Tango Posted December 18, 2019 Area Representative Share Posted December 18, 2019 I have had a corrosion issue with an Emerald too, which I am sure was from condensation. Link to comment Share on other sites More sharing options...
Pauls SLR Posted December 19, 2019 Author Share Posted December 19, 2019 It may have been condensation. I'm wondering whether it would be worthwhile putting a thin bead of silicone around the joints at each end of the casing to prevent water ingress. My car only really comes out sunny weekends so it's never really been drenched on the road. I don't wash it that often either! Link to comment Share on other sites More sharing options...
revilla Posted December 19, 2019 Share Posted December 19, 2019 The casings on the standard MEMS3 ECUs are sealed with a bead of strong silicone all round and I've never seen corrosion inside one of those. Link to comment Share on other sites More sharing options...
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