Author Topic: fried while cranking ?  (Read 8574 times)

Offline uzelac

  • Full Member
  • ***
  • Posts: 118
  • BHP: 4
fried while cranking ?
« on: November 08, 2013, 01:55:37 am »
Hi

I had a strange issue today whice cranking engine after 2-3 months.
While cranking, which sounded a bit heavy, isolation on one of wires started melting.
I cranked it for some 5-6 seconds.

The wire which oveheated is thin (maybe 1mm thick) wire which was soldered to point where power and sensor grounds are connected to common ground. The other end was bolted to chassis.

Can't connect to VEMS any more. There were no funny smells, nor any damage is visible by close examination of whole board.

Can someone tell me what happend ?
Where to expect damage in VEMS if any ?

I will double check everything tommorow and try to connect to VEMS.
If no, can someone tell me what can i do to check which chip died ?

Thanks
N/A 4AGE 16V - 180hp@8000rpm - work in progress :)

Offline VEMS

  • Administrator
  • Sr. Member
  • *****
  • Posts: 487
  • BHP: 22
Re: fried while cranking ?
« Reply #1 on: November 08, 2013, 08:49:30 am »
Was the ecu properly fused with separate 1 amp fuse as instructed in supplied with ecu documents: http://www.vems.hu/download/v3/doc/RescueKit.pdf ?

Was an unregulated booster or charger used during starting ?

Best regards,


Dave

Offline uzelac

  • Full Member
  • ***
  • Posts: 118
  • BHP: 4
Re: fried while cranking ?
« Reply #2 on: November 08, 2013, 11:07:40 am »
ECU is on seperate 7.5a fuse. I remember 5A is recommended, you confused me with 1A now, i got something wrong or something changed in recent years after i assembled my Vems.

Accu charger was connected to battery terminals whole time. Don't know what unregulated means?!
« Last Edit: November 08, 2013, 11:11:05 am by uzelac »
N/A 4AGE 16V - 180hp@8000rpm - work in progress :)

Offline VEMS

  • Administrator
  • Sr. Member
  • *****
  • Posts: 487
  • BHP: 22
Re: fried while cranking ?
« Reply #3 on: November 08, 2013, 05:22:28 pm »
1-3 amp fuse is recommended for ecu supply (1 amp is supplied with ecu). Most simple chargers cannot handle cranking with charger connected and this should be prohibited. They produce high voltage spikes in effort to compensate for high current load from starter. This has probably triggered the ecu internal over voltage protection which should blow ecu supply fuse.

If any damage is suspected you can always use repair/upgrade product in VEMS webshop: http://shop.vems.hu/catalog/repair-upgrade-p-103.html

Best regards,


Dave




Offline Kamuto

  • Hero Member
  • *****
  • Posts: 814
  • BHP: 19
Re: fried while cranking ?
« Reply #4 on: November 09, 2013, 08:20:34 pm »
ground from engine to car body is still in place?
Vems installer in Lithuania
valdas.sunokas@gmail.com

Offline uzelac

  • Full Member
  • ***
  • Posts: 118
  • BHP: 4
Re: fried while cranking ?
« Reply #5 on: November 17, 2013, 02:07:14 pm »
ground from engine to car body is still in place?

It was there all the time.
As car stood for a long time I retightened it a bit. Maybe it cranks a bit better now, not sure.
It cranked a bit heavy earlier, but there were no issues with VEMS, it fired and run good.
N/A 4AGE 16V - 180hp@8000rpm - work in progress :)

Offline Kamuto

  • Hero Member
  • *****
  • Posts: 814
  • BHP: 19
Re: fried while cranking ?
« Reply #6 on: November 21, 2013, 02:30:07 pm »
i had one fried, p259 chip died, but the problem was no ground connection between engine and chassis, guy who replaced engine just forgot it.. it cranked really bad..
Vems installer in Lithuania
valdas.sunokas@gmail.com

Offline uzelac

  • Full Member
  • ***
  • Posts: 118
  • BHP: 4
Re: fried while cranking ?
« Reply #7 on: November 25, 2013, 12:46:58 pm »
Looks I was lucky after all, one of the relay's died and VEMS is 100% OK.
Replaced it, rechecked all fueses and it fired like a champ.
Can't find fuse below 5A so using that one for VEMS but will keep looking.

From now on, i will check grounds better, especially if car had stayed for long :).

Thanks
N/A 4AGE 16V - 180hp@8000rpm - work in progress :)