S2 Electric and Starter Motor Problems

[scotboy15]

Well my Elise problems continue! No one said Lotus ownership would be easy!

I went away for a week with work (during the time when it was pretty torrential rain) and when I returned the battery on my Elise was dead which I found strange as its never happened before. I charged the battery and am now seeing some strange behavior

Basically, as soon as I deactivated the alarm (so the key isn't even in the ignition) the engine tries to start and keeps turning over. Reactivating the alarm stops it and then eventually if you start it yourself using the ignition and turn it off it sometimes stops it attempting to restart itself.
If that problem doesn't happen then it appears the starter solenoid is firing whether the key is in the ignition or not and occurs both when the engine is on and isn't. On top of that, when you turn off the car there is a high pitched whining noise that comes from the engine for about 15 seconds or so.

I know it sounds really weird, but does anyone have any suggestions as to where to start with this or what could be wrong? I may have missed some details out so any questions feel free to fire them my way.

[robin]

I would guess that you have water in your MFRU I suspect ... the MFRU lives underneath the ECU and should be secured against the ECU plate but all too often they are left dangling. You go over some bumps, crack the case, then water runs into the unit and causes chaos. This also flattens the battery.

To access the MFRU you can look underneath the ECU rain cover - in the engine bay, on the boot wall, passenger side, black box about 3"x2"x6" with two wire blocks running into it.

Cheers,
Robin

[robin]

It's #9 in this picture

[scotboy15]

Cheers for that Robin.

I'll check it over the weekend but whats the best course of action? Can drying it out fix the problems and if so is it easy to remove or is it a case of getting a replacement?

[roadboy]

Robin is spot on with his diagnosis.

Just get a replacement. It will be corroded inside. They are a standard Rover part so you could pick up a cheap second hand one from a scrappy.

HTH

Dan

[robin]

Yeah, just get a replacement - water in there causes electrolytic corrosion that eats the PCB tracks so you're as well to just source a replacement. Make sure it's a MFRU though and not the HVAC control unit that looks the same but lives under the front wheel arch (where else!).

Cheers,
Robin

[scotboy15]

Robin and Dan,

Thanks heaps for your diagnoses as it was spot on. It took a bit of locating but removed the MFRU and even before I took it apart I knew it was gone as I tipped it up and green, corroded water poured out of it.

Bought a new one for £50 and fitted it and its working perfectly.

Have put some pictures below but again, thank you heaps as it saved me a potentially mammoth mechanic bill!

[robin]

Is the first picture new one installed?

If possible, I would rotate the unit through 90 degrees so that the connectors don't point rainward. There should be a metal clip on the ECU backplate that will accept the MFRU ....

Cheers,
Robin