[sabieworld]

Hi all,

My civic has battery drain issue. further inspecting, I found that my PGM-FI main relay and Ignition coil relay are on even when the Ignition is off. I checked the relays. those are not faulty. Relays are on because there are always voltage in the sockets.

when only one relay is removed, the voltage in the socket was 10.5 (battery voltage 12.5v)
when both relays are removed the voltage was something between 12 and 12.5

from fuse box diagram, I understood that relay's positive pin is always connected to battery +ve terminal. and the ground is supplied from ECM when ignition is on. so there is a chance that relay's negative is shorted to body ground which makes a voltage and enables the relay. but when I checked the continuity between body ground and relay socket's negative pin, there were no continuity.

can u guys pls guide me find out what causing this voltage..?

 

[richadam]

Hi all,

My civic has battery drain issue. further inspecting, I found that my PGM-FI main relay and Ignition coil relay are on even when the Ignition is off. I checked the relays. those are not faulty. Relays are on because there are always voltage in the sockets.

when only one relay is removed, the voltage in the socket was 10.5 (battery voltage 12.5v)
when both relays are removed the voltage was something between 12 and 12.5

from fuse box diagram, I understood that relay's positive pin is always connected to battery +ve terminal. and the ground is supplied from ECM when ignition is on. so there is a chance that relay's negative is shorted to body ground which makes a voltage and enables the relay. but when I checked the continuity between body ground and relay socket's negative pin, there were no continuity.

can u guys pls guide me find out what causing this voltage..?

A few things to note. 14.5 indeed suggest/confirms the alternator is charging. Yes after taking it off charge, even with cables disconnected, it would settle to what should be 12.5 -12.6v fully charged battery in good condition. You went the right direction by pulling the fuse. You can do this with other systems/components to see if they are the culprit. A bad battery will initially charge, but then drop voltage with no draw, so ensure the battery is good before driving yourself crazy. Finally, one simple check is to park it in a dark spot at night, in a garage is better, pull the key and exit like parking it overnight, then look very closely for ant lights remaining on. Trunk, glove box, dome light, accessories like aftermarket cameras, stereo, or others.