Recently I posted about having an issue with my batteries, the passenger side is much lower than the driver side, 680CA vs 1050CA, I don't think I have parasitic drain and I cleaned the terminals and connections on the battery and the ground on the fender. But it starts slow and I kinda think its starting slower than yesterday. Could the battery not be accepting a charge? I suck at electrical and is the last thing I want to work on my truck. Thanks in advance for the help. BTW the batteries are Motorcraft Max Batteries and were bought in NOV 2015.

 

Could be. Did you check the LARGE ground connections on either side of the block toward the fan?

Not sure if you have the time to have your truck down, but you could remove the suspected bad battery from the circuit and check the voltage. Leave it sit for overnight or several hours and see if it is discharging by itself. Be sure to cover or insulate the terminals to prevent accidents. I like to use T-shirts and painters tape to insulate the terminals.

No matter how much you clean and check grounds and positive connections, if the battery is bad nothing will change that.

 

Where on the block are they? I did a cursory check yesterday but I couldn't find them. TIA

 

Let me see if I can find a picture on Google, standby...

EDIT: Couldn't find any clearly defined pictures. Best description I can give you is to stick your head underneath the truck and slide under it further until you are looking at the main crank of the engine. Then, to each side (passenger and driver) there will be a large black cable attached to the block. Remove those bolts, clean everything with a wire brush really well and put it back together.

The driver side negative goes from the battery down to the engine block, you could trace that if you like. I cannot remember the exact routing of the passenger side battery, but the block connection is very similar. Once you find them, you will probably laugh a bit.

 

Never mind should've fully read your reply, trying to do CAD and pray my truck starts going home lol.

 

Unhook both battery grounds when you park for at home for the night and check each individually for voltage should be the same as both were a set seconds ago. Go out in the morning and check each again. Both should be the same or very close If not one may be going bad. When I did this one was under 10 volts in the morning.

As long as each has a good ground and power connection I do not see anyway the alternator could only charge 1 battery. Have you verified the alternator is charging?

 

Yes, Brandon I know the alternator works (voltage goes up to 14.3 on my CTS2), I will try that and will report back

 

Update: went to my work and tested the problem battery, got a 370 CA reading, its supposed to be 1000CA. I don't know how Crowley Ford measured 700CA on Tuesday. But I went in today to get my warranty battery and they gave me a hard time on getting the warranty saying "it didn't read bad" took some complaining to get them to warranty the battery. I wouldn't recommend going to Crowley Ford to anyone on here that lives near Bristol Connecticut.

 

Rotate the drivers side and passenger side battery every year. Passenger side gets the harder initial draw during starting and is usually the one to go bad first if i don't rotate. Also check the water level in them at the same time.

 

It is becoming more and more difficult to find a good and honest dealer.

When I replaced the Orielly brand batteries with NorthStar AGM's I took the Irish batteries into the store and said I would like to have these tested and replaced if you find they are faulty. The guy behind the counter asked if they were bad, to which I replied "I think they are". He said OK, if you want to grab 2 off the shelf I will start the process.

Walked out with 2 new batteries which I sold on C-list at 1/3 the cost of what they were to a local guy that could use them.

 

This is what I discovered, my passenger battery would always fail after about 3 years, the driver's battery would be fine. I am going to start rotating them.

 

Never considered that. Thanks for the tip!