Intermittent P0138 and P0158

[Jay MacLeay]

My CEL keeps coming on and going off. When it is on, I am getting p0138 and p0158 codes. Also, while I'm driving, sometimes when I hit a bump the power to the engine will cut out shortly and the instrument cluster will reset. I'm assuming I have a short somewhere. I recently found that the ground wire that connects to the engine block was not connected. I have since reconnected it. Any thoughts as to where to look?

@Chris @Jerry Bransford

 

[Jerry Bransford]

My CEL keeps coming on and going off. When it is on, I am getting p0138 and p0158 codes. Also, while I'm driving, sometimes when I hit a bump the power to the engine will cut out shortly and the instrument cluster will reset. I'm assuming I have a short somewhere. I recently found that the ground wire that connects to the engine block was not connected. I have since reconnected it. Any thoughts as to where to look?

@Chris @Jerry Bransford

Not likely a short, more likely an intermittent connection at the battery or where the battery connects to. Closely examine all the wiring and connectors that are in any way connected to the battery or to the Power Distribution Center. They are getting old enough to be corroding/coming apart inside of where the wiring is crimped into their connectors.

 

[Jay MacLeay]

Not likely a short, more likely an intermittent connection at the battery or where the battery connects to. Closely examine all the wiring and connectors that are in any way connected to the battery or to the Power Distribution Center. They are getting old enough to be corroding/coming apart inside of where the wiring is crimped into their connectors.

Thanks, Jerry. That makes sense. I have one of those Smittybilt duel battery trays w/ 2 optima red tops and an isolator. I've noticed that the aux battery seems to be acting funny. The aux battery has stopped working unless I push on it a little bit. Then it will work. I leave a light on that is connected to the aux battery. When I push on the battery/tray system the light will come on. If I play w/ the neg. terminal on the aux battery while pushing the battery into the position where the light comes on, the light will then flicker as I slightly move the neg. terminal. I know this now is probably more specific to my Jeep and my system and would require actually looking at it to completely figure out what is going on. My assumption now is that the aux battery is bad. My question now is, could that bad battery be causing the issues I'm having w/ the main battery/electrical system? Could replacing the aux battery fix all my issues?.... All my Jeep electrical issues haha

 

[Jerry Bransford]

I'm betting at least one of those many extra connections required for your dual battery setup is causing problems. A bad battery can also cause problems for the good battery if they're not connected properly.

Optima has developed a REALLY bad reputation in recent years since JCI bought them and moved their manufacturing to Mexico. Personally, I'd get rid of the Optimas and convert back to a single battery using a good quality AGM battery. Odyssey if you can afford it, they are known to last ten years.

My last Odyssey battery lasted over ten years and I'm now on another. Dual batteries aren't really needed, even if you do a lot of winching like I do. I've even winched my Jeep off the trail on my single Odyssey battery without the engine running after it died from a bad ignition coil. I didn't even need a jump start once I replaced the ignition coil.

 

[Jay MacLeay]

I'm betting at least one of those many extra connections required for your dual battery setup is causing problems. A bad battery can also cause problems for the good battery if they're not connected properly.

Optima has developed a REALLY bad reputation in recent years since JCI bought them and moved their manufacturing to Mexico. Personally, I'd get rid of the Optimas and convert back to a single battery using a good quality AGM battery. Odyssey if you can afford it, they are known to last ten years.

My last Odyssey battery lasted over ten years and I'm now on another. Dual batteries aren't really needed, even if you do a lot of winching like I do. I've even winched my Jeep off the trail on my single Odyssey battery without the engine running after it died from a bad ignition coil. I didn't even need a jump start once I replaced the ignition coil.

I removed the second battery and am just using one battery (optima red top... don't have the money to shell out for a new battery). That has fixed this issue. Thnx for the help. That's pretty impressive that your Jeep didn't need to be jump started!