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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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Voltage drops on pin 5  at the relay.  Tried couple of them ( all from the car so they were old )   they all drop voltage :huh:  will  buy a new relay and  try with new one.

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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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What is the terminal connection like on pin 5 of the relay if that was not making a good connection changing relay will have no effect as the issues is the actual terminal 

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Terminal conection looks ok also contacts in there looks ok   is it possible that some ground from the ecu is playing up... 

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If you are measuring that voltage drop across the relay and using the same ground for each measurement then it is not ECU related. There is something up in that relay area.

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In the ECU is it giving a low battery voltage or only the errors you showed in the first post?

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So i cut the wire from pin 5  out from eccs  and mesured pins on ecu 59, 109, 49  they stil have the same voltage oround 9v  :huh: 

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wired in ecu directly and now it is error free  voltage is ok and car starts  but dies right after  ( but i think that this  is a map foult ) 

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