MikeMolloy Posted December 11, 2012 Share Posted December 11, 2012 Right, I have a wiring diagram of the MFRU in my hand (although I can't find the original on the web!) It contains the Fuel Pump Relay (which is energised by Ignition ON and a signal from the Engine ECU), the ECU Relay, a "Spare Relay" and the Starter Solenoid Relay. The circuit for the starter is Ignition -> Start button -> Relay Coil. So, as someone correctly posted above if you have the ignition on pushing the start button should crank the engine regardless of immobiliser status. If it doesn't crank then you have a flat battery or a MFRU problem. Deffo check the photos on Angus' website and make sure it is plugged in! Link to comment Share on other sites More sharing options...
Jason Plato Posted December 11, 2012 Share Posted December 11, 2012 I think the black box next to the fuel cut off switch is the fuel vapour canister - about the size of a match box. Link to comment Share on other sites More sharing options...
Dave B Posted December 11, 2012 Author Share Posted December 11, 2012 MFRU is definately connected, the other black box is as Dave Jackson says, the fuel vapour canister. I have been at work this afternoon so will get stuck in with the multimeter tomorrow am and try and trace the starter and fuel pump faults. I think they have messed with something and not connected it back, or something similar. Then again it could be pure coincidence Link to comment Share on other sites More sharing options...
charlie_pank Posted December 11, 2012 Share Posted December 11, 2012 Just to save you some time try pulling out the MFRU plug and reconnecting it. I'm really struggling to think what else would cause the 2 failures you're describing and for my sins I'm a LOT more familiar with the wiring of the K series than most. Link to comment Share on other sites More sharing options...
Dave B Posted December 11, 2012 Author Share Posted December 11, 2012 Charlie P. Its got me completely stumped also. I think all I can do now is go through the electrics logically. Although saying that I was never great with auto electrics, but am willing to get stuck in. If there are any folks out there want a cheap holiday in Gran Canaria with some great blatting in my 7, get it going for me and you're on for some of the best roads ever. See pics in Nov. Low Flying Dave B Edited by - Dave B on 11 Dec 2012 20:39:49 Link to comment Share on other sites More sharing options...
Klunk Posted December 11, 2012 Share Posted December 11, 2012 Dave, I'm sure you've already done this, but carefully look over the wiring around the MFRU/ECU area before you start checking with a multimeter. On the way to this year's March Llandow I had a similar issue. After pulling in for petrol, my car would not restart. I eventually found a hidden loose spade connector where the ECU loom is spliced into the Caterham loom. However I spent an hour with a multimeter before I did this I'm sure this won't be your issue as your ECU has got power, however check for disturbed connectors where the mechanics are likely to have been working. As Charlie says, disconnect/reconnect all plugs as there's quite a bit of stress on the loom around that area, and a watch on a careless wrist can wreak havoc. With your immobiliser disabled in the Emerald, I would check all the wiring around the MFRU first, followed by the power feed to it and any associated earths. Good luck Giles Edited by - Klunk on 11 Dec 2012 22:00:38 Link to comment Share on other sites More sharing options...
Tom White Posted December 12, 2012 Share Posted December 12, 2012 For MFRU connections you might want to look at my old EU2 wiring website here. It's based around the MEMS ECU but the bits that hang of it are just the same. I have just relaunched this site and will add some stuff on the emerald in the New Year. Good Luck Tom Link to comment Share on other sites More sharing options...
Mankee Posted December 12, 2012 Share Posted December 12, 2012 Very handy website you have there, Tom! I have bookmarked it for future reference. It will be useful for making a new loom. Link to comment Share on other sites More sharing options...
Rob Walker Posted December 12, 2012 Share Posted December 12, 2012 If you remove the cover off the MFRU it is possible to operate the relays manually with your fingure. By pressing each one you will be able to identify what each relay does as one should activate the starter, one the fuel pump the others are the horn and the lambda sensor. When you have identified the fuel pump you can jam this in the energised position with a match stick. Then operating the starter relay the engine should crank. The Red light on the Emerald should change from Red to Green to indicated that the Emerald has recognised the crank pattern and is revolving above 200 rpm, the engine should start. Good luck. I would be happy to come out to Grand Caneria and fix it for you. Rob Link to comment Share on other sites More sharing options...
Jason Plato Posted December 12, 2012 Share Posted December 12, 2012 or short a 12v feed to the fuel pump wire and bypass the MFRU for test . Link to comment Share on other sites More sharing options...
Dave B Posted December 12, 2012 Author Share Posted December 12, 2012 Well. Many thanks to all the responses to my urgent plea. This morning was my first opportunity to take a look myself and I fixed it in around 2 minutes. It was the ECU fuse at the bottom of the fuse box. I have replaced the 20a with a 30a and car started first time. I have to say I did see the mechanic check the fuses but he must have missed this one. Now just have to get emissions checked and go for another test. Once again many thanks to all you blat chatters. Dave B Link to comment Share on other sites More sharing options...
Stationary M25 Traveller Posted December 12, 2012 Share Posted December 12, 2012 Hurrah. The remote power of Blatchat. Link to comment Share on other sites More sharing options...
MikeMolloy Posted December 12, 2012 Share Posted December 12, 2012 Link to comment Share on other sites More sharing options...
paul seymour Posted December 12, 2012 Share Posted December 12, 2012 Damn, i was just on my way for a cheap holiday in gran canaria with blats on the best rds ever. 😬 Pleased to hear you are back up and running and well done to all who gave advice Great club. Link to comment Share on other sites More sharing options...
diggerman Posted December 12, 2012 Share Posted December 12, 2012 Well done Ian. You were one of the first to respond and hit the nail on the head! Peter Link to comment Share on other sites More sharing options...
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