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Low voltage at ECU


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Posted this in the other thread  but noticed  that it vas for vipec ^_^
Hi i have problem  with low vlotage on ecu but  eccs relay is OK  ( replaced and masured )   voltage sometimes drops as low as 9v  if i conect  original ecu voltage still drops but not so much 11.4v  any ideas?  car is  s14a silvia with swaped rb25 det s2    i am chasing this electrical phantom  for 2 days  now and going nuts...

I get this errors ( atached  image )   and atached log of runing car

Lem g3 updated to g4 with adaptalink 

Best regards

event log.jpg

Log 13-07-19 7;04;50 pm.llg

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Update: hardvired eccs  and now i have   same voltage  on ecu  but  error on an volt 4 is still present sometimes lov sometimes high.. 
also i mesure the resistance on  ground vires around 15ohm  should i consider to wire new grounds ?  or is it posible that contacts are bad? 

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What is AN Volt 4 function set to?  I think from memory it is the narrowband oxy sensor so you will need to change the fault settings to low = 0.0V and high = 5.0V.

Your resistance to ground doesnt sound right - how are you measuring this - between which pins/points?

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i have wideband conected to  an v4  i will set  the value  to  what you recomend.  i mesured resistance betwen ecu ( not on adaptalink )  and   chasis   if this is not ok will direct conection  on wires betwean ecu and adaptalink sort this problem out ? 

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Update:  I presed conector deeper in to the  conection and the resistance on grounds is gone. But low voltage is still present,  also on pin 16 i have  same power as on the  59 (9-10v). 
When i hardwired the eccs relay the car  could berely start and die  right after.
if i put everything  back to original state( no hardwire ) when i  turn the key  fuel pump is runing all the time  does not stop( priming in ecu is set to 3s) , when car starts  sometimes it idles ok but when  i touch the gas pedal  some reley at my foot start kliking ( lhd ) and car dies  or berely stays on  and recover ( maybe fuel pump reley ? )  ...   also ecu disconects while cranking engine...  realy lost here :wacko: 

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i  have mesured   pins on eccs and pins on the ecu  and mesurements are: 
ECCS reley: pin1=12.26v  pin2=11.20v  pin3= 12,26v  pin5= 8.9v 

ECU: pins 49,109,59 and also at crank sensor all have 8.91v airflow meter is deleted  ( i am using IAT sensor ) 
pin18=  pin2 onfuel pump reley have 9.53   and fuel pump directly have 11.9v

If i jump wire the  eccs  reley i get normal voltage ( same as batery ) but car dies or it leans out  and dies...  


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