Quinten Posted March 30, 2017 Posted March 30, 2017 That's my car It seems that my MBE 956 (ver C) ECU is not working. I'm at a loss why. It was working when removed from the car my engine came out of, and has only been stored in the garage until the last couple of days/week when I finally came around to fitting it. The plug to supply the ECU has 4 wires: Permanent 12V Ignition 12V Fuel pump Tacho How difficult can it be?!? Can anyone with the same/similar ECU tell me how the two relays 'operate'? They both are fed the Permanent 12V on 30, and the ECU relay 'relays' that when the Ignition 12V is activated, but the other relay, which should control the fuel pump, does not 'relays'. I swapped the relays themselves around to ensure they are both working, and it made no difference. I got no 12V on 85 or 86, which is strange as some current must flow if it switches the ECU relay? I opened up the ECU, and it all looks in order (quite fresh actually). I could not see 12V on pin 2, which I don't understand either... Quote
DamperMan Posted March 30, 2017 Posted March 30, 2017 Surely one wire has to be Earth ? It can't all be lives Quote
Quinten Posted March 30, 2017 Author Posted March 30, 2017 There is a separate earth wire, which I've put directly on the battery (was first on the chassis, but made no difference). Quote
corsechris Posted March 30, 2017 Posted March 30, 2017 I'm not familiar with the specific ECU but they usually switch relays by providing a switched ground, so as you noted, you should most likely have (a probably ignition switched) 12V on either 85 or 86 with the other terminal (86 or 85) driven by the ECU to ground. Double check your loom as a first step, make sure you have volts and grounds where you need them. Quote
Kingster Posted March 30, 2017 Posted March 30, 2017 Different ECU but same info applied to my older MBE 992-9A4 FWD-RWD Basic Wiring and Relay info.pdf MBE_967e_General.pdf Quote
Quinten Posted March 30, 2017 Author Posted March 30, 2017 34 minutes ago, corsechris said: I'm not familiar with the specific ECU but they usually switch relays by providing a switched ground, so as you noted, you should most likely have (a probably ignition switched) 12V on either 85 or 86 with the other terminal (86 or 85) driven by the ECU to ground. Double check your loom as a first step, make sure you have volts and grounds where you need them. The plan is tomorrow to wire it all up in isolation. Need to verify the ECU powers up before I can blame my wiring. 15 minutes ago, Chris King - Webmaster and Joint North East AO said: Different ECU but same info applied to my older MBE 992-9A4 FWD-RWD Basic Wiring and Relay info.pdf MBE_967e_General.pdf Sorry, but those documents don't help. The wire colours on the relays are different (and they don't say what the colours actually are) and the wires of the "interface" (= connector with main loom?) don't feature the permanent live. Unless the green (pin 3) for "Taco" (tacho) comes from the ECU relay 87?? Unlikely. Quote
Kingster Posted March 30, 2017 Posted March 30, 2017 Hmm trying to recall what was what on mine. Basically there were 4x wires and I used 3 - a live ignition feed in (purple), orange out to fuel pump and the green wire went to my tacho feed. Other than that, there's the TPS, water temp, air temp, crank, injectors, coilpack, a permanent battery live and a ground. The two relays were for the main live feed and the fuel pump. Didn't have a fan relay on my MBE. Quote
Quinten Posted March 30, 2017 Author Posted March 30, 2017 I received the complete 'engine/ecu' loom, which connects to the injectors, coilpack, AIT, TPS, crankshaft and temperature sensors. So nothing had to be done for that. The only thing I had to wire up was the 4-pin connector (see http://forum.wscc.co.uk/forum/topic/123035-loom-question/ ). My colours are brown (perm 12V) / green (ign 12V) / black/green (fuel pump) / white/black (tacho). Unless I've got it all wrong?!? Quote
Kingster Posted March 30, 2017 Posted March 30, 2017 TBH it's a different ECU so the colours could well be totally different from my MBE Best check with the person you bought it off. Quote
Kingster Posted March 30, 2017 Posted March 30, 2017 Looking at the photo I'd check the colours on the actual loom rather than those on the connector blocks - as they look to have beeen added afterwards and thus could use any old colour wires. Quote
Quinten Posted March 30, 2017 Author Posted March 30, 2017 I'm 99% sure the colours of the wires on both sides of the connector are the same. But then it all goes into a thick black plastic (heatshrink/wrap) bundle, with only a few wires visible at the relays. From googling this site on the ECU I am however under the impression that Westfield just used whatever colour they had in stock, but I seriously doubt the seller will be able to help (although I have contacted him) as he (in his words) "just bought the whole package from Westfield" Even found a thread where it is mentioned they have a 3 pin connector?! Quote
Kit Car Electronics Posted March 30, 2017 Posted March 30, 2017 Can't make any sense of the wire colours, but normally if you have a main power relay and a fuel pump relay, they'd be wired something like this, Q: 1 Quote
Trevor Little (Trevturtle) - Treasurer Posted March 31, 2017 Posted March 31, 2017 Sorry if you've tried this already...but have you tried connecting the ecu to a laptop to see if it's booting up. I suspect it isn't booting up, but checking it it would confirm that the problem is the ecu not booting up rather just a loom problem to the fuel ecu relay. Quote
Quinten Posted March 31, 2017 Author Posted March 31, 2017 @Kit Car Electronics, that's really helpful, thanks! It confirms my own knowledge and gives me points to measure at. @Trevturtle, unfortunately I do not have the serial lead to connect it up to a laptop. Quote
BenD Posted March 31, 2017 Posted March 31, 2017 not the same ecu but the fundaments are the same thats how omex is wired. assuming your loom is a westfeild supplied one and the colours are correct in the chassis. have you checked your fuses. do you have a zetec engine loom and standard westfeild chassis loom i had no power to my ecu but there was a lone brown wire in the zetec loom that plugs into a 3 pin econoseal plug which does power for somethign but i carnt remember what Quote
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