Cannot resolve P0685 Code in 2003 Accord

We may earn a small commission from affiliate links and paid advertisements. Terms

JohnneeO

New Member
Hi Everyone,

I am having a problem with my 2003 Honda Accord LX w/ AT. The current ptoblem is that Code P0685 is coming up, and the transmission is acting strange (slipping, etc.). My mechanic feels he cannot clearly state one way of the other the AT needs to be fixed b/c he cannot resolve the P0685 code.

Recent history with the car is no major problems until Nov. 2010 (over 150K miles). Then the timing Chain slips, and the engine is shot. New (used) engine is installed, Check engine light comes on a day later. Numerous codes (including P0685), also code for the CAT and a fuel soleniod. I had that work done, and then P0685 code remained, and now the AT is acting up. Replaced the PCM (on advice), expecting the that to clear the code. The new PCM has not cleared the code, and the AT is still acting weird. Slips at times, works fine at other times.

My mechanic has been chasing the code but cannot isolate it, and in turn, cannot be certain one way or the other about the AT. He has even reported that AT codes have come on, and then self-cleared, with the P0685 code remaining.He thinks it could be a solenoid from the AT feeding back to the computer, but he cannot confirm.

Found this forum on a web search, and wanted to ask for ideas. Please help!
 
P0685 ECM/PCM Power Relay Control Circuit Malfunction

- ECM power control circuit is open or shorted
- Failed ECM power relay
- Failed ECM


If its not the ecu, as it's been replaced, it's likely the relay where the issue lies.

also, check your battery terminals and connections. a lose feed line could cause power issues.
 
Good ideas, I appreciate the reply.

The relay has been replaced (first thing he did), and then he has gone over the basic electrical connections, going as far to drop a different battery to see if that changed things. No change. Any other thoughts?
 
Problem Solved!!!

The problem was solved, and I have the car again. I drove it home this morning from the mechanic, and it felt solid.

The problem turned out to be a loose ground wire from the PCM to the engine. The specific wire was G101. After that ground wire was cleaned and reattached, Voila! Everything is fine now. No codes, no problems with the transmission, and now the cruise control even works, which had not functioned since the new engine was installed.

What a relief.
 
Can anyone upload a picture for the location of the G101 ground wire? i have the same problem but couldn't locate the G101 wire to replace it.

Thanks guys
 
Back
Top