Alan_M 66 1 Cars Posted August 1, 2008 Bit of a dilemma here. I'm meant to be going to the Ring next Thursday, and my cars ready for a MOT but its not starting. After a check with a meter, there is no power to the fuel pump whilst cranking, and likewise at the green relay under the bonnet. I checked the coil side of the relay (Orange wires, 20C + 20B) for volts and there is sod all whilst cranking, hence an issue with the ECU. To rule out any wiring issues, can someone tell me the pinouts of the ECU connector on a 2 row Mi16? Just want to check the earths etc. Can someone tell me if the ECU has volts to it on the 2nd turn of the key, just before cranking? The K light has been wired up and I'm sure it used to come on on the 2nd notch. Its not, giving me the impression the ECU is either rogered (another bites the dust) or there is no supply to the ECU? Any ideas from anyone? Share this post Link to post Share on other sites
Alan_M 66 1 Cars Posted August 1, 2008 Correction, the K Light does light up. Got the pinouts and there is volts to the ECU and it is earthed. One thing I am doing is charging the battery, as it was a shade under 12v. The battery was charged fully about 2 weeks ago, and wasn't used till a few days ago. Share this post Link to post Share on other sites
S13Nick 0 Posted August 1, 2008 thi happened to a mate of mine. i think it was a knock sensor fuse... iirc. worth a try Share this post Link to post Share on other sites
Alan_M 66 1 Cars Posted August 1, 2008 Just had a read of the pinned 'Motronic Guide', very useful! By the looks of it I have got it mixed up on how it all works. Yes, there is no signal at the green relay (Fuel Pump relay) and this is connected to the ECU terminal 20. But it turns out that this is earthed on ignition being turned on. I have ignored the brown realy (Fuel Injection relay). There should be volts at the brown relay at terminal 1, and at 3 on the green relay which I've got. When ignition is turned on, the battery voltage is passed to the coil of the brown relay, closing the contacts which passes volts the injectors, ECU t35 and the coil of the green relay. On energising the green relay coil, which is earthed via ECU terminal 20, closes contacts and starts the fuel pump. The ECU will run the pump for 1 second to prime and then go open circuit. The circuit will stay open till the ECU gets a signal from the CAS. Been going about this the wrong way, did'nt realise the brown relay (Fuel Injection relay) was part of the equation......... Share this post Link to post Share on other sites
Alan_M 66 1 Cars Posted August 1, 2008 thi happened to a mate of mine. i think it was a knock sensor fuse... iirc. worth a try Not got a knock sensor....... Share this post Link to post Share on other sites
Alan_M 66 1 Cars Posted August 6, 2008 Just to complete this thread, it turned out to be crap multi connectors between the ECU loom and link-loom. Re-terminated all of them and its starts spot-on now. Main give-away was that it had the intermittent starting (click-click-click then it'll start) and a dodgy oil pressure gauge reading. Share this post Link to post Share on other sites
