Lotus elise Crossed Jump leads.

[VINER]

Battery flat on Elise. Rushing and momentarily crossed jump lead. Now car starts just but have to keep it reving if i take foot off accelerator engine cuts out straight away Also alternater light on constantily. Have i cooked the ECM...

[400SE Dave]

Friend of mine crossed over the battery terminals and it fried the ECU. Sounds like you could have done the same

[Norgles]

Could well be the ECU, however it would be worth checking all the fuses, you could be lucky and just have just blown one or two of these. If any are blown the SELOC Techwiki will tell you what they are for. Worth a try!

[VINER]

Fuses all checked..No luck there im afraid. Typical just gone through a top end ovehaul and front clam repair, Test driven few weeks back. Off for MOT today on a right downer now. Looks like self inflicked expence.

[Norgles]

Gutted. I think both the S1 and S2 have some other fuses not found inside the main fuse box, some of which are quite heavy duty have you checked those?

I hope you get it sorted.

[VINER]

Checked the 2 20a fuses along side the ecu aswell as the fuse box thats all the fuses im aware of.
Thanks.

[JBanx]

Could be a bit of fuse wire between the alternator and starter motor. Have a poke around the engine bay

I did the same as you and that was what went on mine! (S1)

[Tonyringtone]

Just a thought, irrespective of having crossed the wires over, I have found after jump starting my Elise or reconnecting the battery, the car usually doesn't tick over on idle. The solution to this is to turn on and activate the ignition circuit on your imobiliser button on your keyfob and then depress the throttle 5 times over a 10 second period. Then turn the key to start as normal.
This works every time, so may be worth trying before you start spending out! Good Luck

[VINER]

Found 80A alternater fuse blown, 'Replaced' Car drives ok but just cuts out soon as you take you foot off accelerater pedal.

[Scuffers]

if your lucky, the idle valves just stuck/blown, that are relatively cheap/easy to change.

if your not lucky, it's the ECU..... but that fact it still runs the car would suggest it;s not the ECU (hardly conclusive I know)

[VINER]

Thanks for all the advice but looks as if its the ecu, Iv got no output to the icv. Fitted another icv in fully open postion now idles eraticly between 1000, to 2000 RPM.

[Stitch]

VINER said:

Battery flat on Elise. Rushing and momentarily crossed jump lead. Now car starts just but have to keep it reving if i take foot off accelerator engine cuts out straight away Also alternater light on constantily. Have i cooked the ECM...

Did the battery run flat after being left for a long time?

Issue you are having may have nothing to do with the crossed jump leads.

Does it start and hold a lumpy idle but then as soon as you rev it won't return to idle (i.e. just stalls)?

I had exactly the same issue after letting the battery run down over a couple of months standing.

Solution was a long drive (and looking like a cock as I had to keep the revs up when sat at traffic lights etc). ECU just needs to recalibrate itself. But I am talking about an hour or so drive to sort it.

[VINER]

Thanks for that.The car had been running ok. Battery was flat for only a matter of days and after Crosed Jump leads would not tick over at all Swapped icv that was in the fully open postion rather than the one that was on there, that was clsed and changed from no ticking over at all to running high tick over going for 2000 to a 1000 continosly But i have not given in a decent run as Need to mot.

[VINER]

Thanks James That might be the best thing to do is get it checked.