Driver side battery venting?

[BrettLisk]

see my first post --




That being said, 12.2 volts and 11.4 volts is too LOW for EEITEHR battery and 12.2 volts in the PS battery does not necessarily, though still could, indicate a bad cell.

OP, curious you can SEE if either battery case is swollen?? If so, the overcharging has been going for a awhile.

Surprisingly neither is swollen or getting hot. Waiting for school to let out currently.

 

[PWong]

The ONE and ONLY ONE thing that ECM looks at/cares is to see the DRIVER SIDE BATTERY voltage matches with its TARGET system voltage.
And the target system voltage depends on the DRIVER SIDE BATTERY temperature sensor signal underneath the battery.
Passenger side battery voltage is never in ECM's mind!

The charging voltage can be much higher than 15V when the driver side battery voltage is far from the target voltage.
Hence its normal/common to see driver side battery undercharged and passenger side battery overcharged when the crossover cable is BAD.

 

[PWong]

So what's the voltage that ECM sees (at OBDII port) when running?

Interesting case to follow!

Was it an overcharge issue to cause the driver side battery vent but not passenger side???

 

[BrettLisk]

Was it an overcharge issue to cause the driver side battery vent but not passenger side???

I'm not sure, the alternator is new, but the load test will tell me if it's a bad cell or not. I'm at my wits end.

 

[PWong]

It's hard ( for me) to concur that its an overcharged issue.

 

[DavidC]

Update ?

Dave

 

[BrettLisk]

Ok guys,

Sorry for the delay, hours have been all over the place. The culprit was a dead cell in the driver side battery. Passenger one tested fine. Thank you to everyone that tolerated my stupidity and asking you to diagnose a problem with little to no information.

Brett

 

[DavidC]

Thanks for the update. This may help someone in the future.

Dave

 

[PWong]

So the venting was caused by a dead cell and hence the battery experienced overcharge with the normal system charging voltage .

 

[seafish]

I mentioned a bad cell in my post as likely cause of the DS side overcharging, I just thought that it would more likely be on the PS side. Proofed wrong AGAIN!!! LOL!!! Thanks for the update.

 

[BrettLisk]

I mentioned a bad cell in my post as likely cause of the DS side overcharging, I just thought that it would more likely be on the PS side. Proofed wrong AGAIN!!! LOL!!! Thanks for the update.

Pm me your PayPal, I'll send you 10 bucks for being the most correct haha

 

[seafish]

pm me your paypal, i'll send you 10 bucks for being the most correct haha ��

....lol !!!

 

[PWong]

a bad cell as likely cause of the DS side overcharging, I just thought that it would more likely be on the PS side. Proofed wrong AGAIN!!!

Any battery with a dead cell (one cell less) will experience overcharge with the normal system charging voltage.

So if just one battery vents and the other is good then it's that battery defective.System charging voltage is normal.

If it's the PS battery vents and the DS battery LOW/drained then it's the crossover cable/connections defective. System charging voltage is high since ECM sees the DS side voltage low. Check gauge light will be ON in this case.


If BOTH batteries vent then it's the alternator or the ECM or both batteries are defective. System charging voltage is high.

 

[PWong]

passenger side I'm getting about 12.2 and on the driver side I'm getting about 11.72 volts

This was a sign of bad crossover cable or defective DS battery.
BUT the PS battery was good and not overcharged then it's NOT the crossover cable.

 

[DavidC]

Correct me if I am wrong but the charging is taken care of the PCM not the ECM.

Dave

 

[PWong]

There is only ONE module: Engine Control Module ECM on the truck (3rd gen) that covers the job of PCM and TCM.

 

[DavidC]

There is only ONE module: Engine Control Module ECM on the truck (3rd gen) that covers the job of PCM and TCM.

Live and learn

Dave

 

[muchsnow]

https://www.solar-electric.com/midnite-solar-battery-hydrometer.html

https://www.altestore.com/store/dee...l-hydrometer-for-deep-cycle-batteries-p11208/