[[beetlegeuse]]

Hi guys. I need some help!

Our 2004 element 4wd auto transmission with no modifications is behaving badly. At low RPM the accessories sometimes momentarily turn off - fan/HVAC stops, radio silences, etc. At the same time, a bunch of indicators flash on the instrument cluster (abs, etc) then power returns. Sometimes it's almost unnoticeable because it happens so quickly, other times the car has died. The more severe instances have resulted in the check engine light coming on. The light generally goes out and the car seems to start and run normally until these same symptoms reappear with the exception of the airbag light which stays on.

I searched through the archives and only found one other reference to P0685 but some of these symptoms seem fairly common...

I took it to the dealership. They recommended an ecm relay and ecm replacement. We replaced the relay but not the ecm according to their procedures.

The problem came back within a day so I returned to the dealer this morning. The computer showed DTC P0685 (losing power voltage in the ecm). They indicate that the optima battery is providing only 17 CCAs but the starter and charging systems are fine. I'm off to replace the battery even though she seems to start like a champ... dealership wants to address the issue ("if it recurs") with a known good battery.

Is it plausible the battery is causing the problem with the ecm? Any thoughts y'all have are welcome

thanks!

 

[MikeQBF]

Yes, intermittent battery or intermittent connection to it would result in your symptoms. That you have an Optima raises the likelihood of battery going south in this way, significantly.

 

[[beetlegeuse]]

Thanks, Mike. Got a new battery in there...the optima lasted 2.5 years.

I haven't seen the above described symptoms reappear, but we probably need to drive a bit more to be sure. It seems to operate more smoothly at idle speed whether underway or parked with the new battery, so that's a great sign.

Thanks again! I'll post up if the saga continues.

 

[TOMATO]

Same Problem

I'm having the same problem as the original post. Wondering if there is an update, or any suggestions I should try. I already blew $50 on the diagnostics for them to just tell me to go to the dealer. They said it could be fixed if the ECM/PCM is updated, but it may need to be replaced. I have no idea how much this would cost. I replaced the battery probably 2.5 years ago and have about 140,000 miles on the car total. I lose radio power when I have my AC running occasionally, but today I had the RPMs go up and a malfunction light come on. Any suggestions would be appreciated.
Thanks!

 

[sschuyler]

Same issue

Getting a P0685 code. Radio cuts out, Engine light is on, gas gauge acting weird, etc. etc. All symptoms started within the last week or two. 192,000 miles, 2004.