P0685
P0685
Greetings
2015 Fit EX automatic 91K
I have been experiancing an ocaisional loss of power that lasts 1 - 2 seconds that returns to normal power.
This has happend on and off over the last few months
The last time a code of P0685 was thrown, I have since cleaned up my grounds, battery terminals, checked for open contacts.
what else should I do, i have noticed other hondas have this error, but have not seen any Gen 3 postings.
Thanks
2015 Fit EX automatic 91K
I have been experiancing an ocaisional loss of power that lasts 1 - 2 seconds that returns to normal power.
This has happend on and off over the last few months
The last time a code of P0685 was thrown, I have since cleaned up my grounds, battery terminals, checked for open contacts.
what else should I do, i have noticed other hondas have this error, but have not seen any Gen 3 postings.
Thanks
ECM / PCM internal circuit malfunction (Power control circuit)
I was looking for the ECM relay
I guess it is under the dash, does a panel come out pretty tough to get in there
battery is less than a year old
charge at rest was 13.15
thanks
I was looking for the ECM relay
I guess it is under the dash, does a panel come out pretty tough to get in there
battery is less than a year old
charge at rest was 13.15
thanks
So the car losing power briefly has not gone away, and after stalling out in rush hour traffic, with a "Check Charging System" warning on the menu warning display
I dropped it at a honda specialist shop.
Battery checks out, after initially targeting the alternator, and swapping out with a known good alternator
No dice
2 relays were deemed dubious.
but no fix of the problem.
the were kind and only charged me for 2 hours vs. 10.5 of real time
the recomended a honda dealer as they would have a better Oscillope and data to test.
But reading the reviews of of the honda shops around me doesnt seem worth the ride.
So I am at an impasse
I dropped it at a honda specialist shop.
Battery checks out, after initially targeting the alternator, and swapping out with a known good alternator
No dice
2 relays were deemed dubious.
but no fix of the problem.
the were kind and only charged me for 2 hours vs. 10.5 of real time
the recomended a honda dealer as they would have a better Oscillope and data to test.
But reading the reviews of of the honda shops around me doesnt seem worth the ride.
So I am at an impasse
On the pushbutton start Fits, I've long believed that the circuit design is inadequate to buffer the load at startup. As a result, both the start switch and the starter are prone to premature failure, and when one goes, it's often ascribed to the other. Honda has recently started goodwilling the switch if it goes - but not the starter. But you wouldn't get a PCM/ECM error code off a bad starter or start switch - you'd know because the car would be hard or impossible to start.
I hope you're not running into a bad ECM, that would not be cheap to replace.
I hope you're not running into a bad ECM, that would not be cheap to replace.
Did the new PCM solve the issue? I am running into the same problem with my 2016 EX with 110k miles.
yes this solved my issue, they also replaced my sparkplugs as the wrong ones were in there (a different non honda shop put them in) and a temp sensor
they did do my ignition button replace on the factory recall call
kinda spendy $1400.00
this did cure the problem though.
they did do my ignition button replace on the factory recall call
kinda spendy $1400.00
this did cure the problem though.
That's good to hear, and thanks for the fast reply! 1400 is still cheaper than having to buy a new car that doesn't turn itself off at least. Mine has been at the Honda dealer for 8 days now with them still trying to figure it out. They keep insisting the PCM is fine even after going through the grounds, relays, connectors, and playing phone tag with the Honda Tech line...
The codes present when I scan seem to change, but P0685 is always stored under permanent codes. Other codes that have popped up and went away on their own were P011A and U0401. Typically the CEL is on and will sometimes turn itself off, but with the P0685 still being there in the background. One of the times it stalled and started up again it lit the dash up like a Christmas tree. CEL, TPMS, ABS, Traction Control, etc.. were all lit up, but no additional codes to explain the individual lights.
Symptoms are random stalling and will usually kick back on by itself after ~1 to 5 seconds. It almost feels like an old traditional auto car that has a slipping transmission. Not a big deal around the neighborhood, but it always seems to do it at the most inopportune spots/time (intersections, merging, passing...). I am fairly mechanically inclined and do all of my own maintenance using genuine Honda parts either on time or ahead of time to be on the safer side. This was the first time I had to take it to the dealer (or any shop) for anything besides alignments and mounting/balancing tires since I got it back in Nov 2015. So if I have to pay them 1k to get my car back, so be it at this point. I just want it to run properly and consistently again.
EDIT: Freeze frame data all seemed to be within normal parameters as well. Only thing that seemed off was the engine run time was 1 second when the code was thrown. Voltage, temps, and pressures all looked good and were reporting properly.
Symptoms are random stalling and will usually kick back on by itself after ~1 to 5 seconds. It almost feels like an old traditional auto car that has a slipping transmission. Not a big deal around the neighborhood, but it always seems to do it at the most inopportune spots/time (intersections, merging, passing...). I am fairly mechanically inclined and do all of my own maintenance using genuine Honda parts either on time or ahead of time to be on the safer side. This was the first time I had to take it to the dealer (or any shop) for anything besides alignments and mounting/balancing tires since I got it back in Nov 2015. So if I have to pay them 1k to get my car back, so be it at this point. I just want it to run properly and consistently again.
EDIT: Freeze frame data all seemed to be within normal parameters as well. Only thing that seemed off was the engine run time was 1 second when the code was thrown. Voltage, temps, and pressures all looked good and were reporting properly.
Last edited by GXOR; Jun 10, 2021 at 03:20 PM.
pretty much my symptoms
the stalling, warning lights, the U0401 looks similar to mine, incorrect spark plugs for me they would be fine on a cold engine but once warmed up, the code, to much gap on the plug.
been a month or so since the fix no problems, keep waiting for that stall but does not happen
I did do my injectors previously, 91K as my car is an 2015 and i was getting the injector code, did coil at that time also.
good luck
the stalling, warning lights, the U0401 looks similar to mine, incorrect spark plugs for me they would be fine on a cold engine but once warmed up, the code, to much gap on the plug.
been a month or so since the fix no problems, keep waiting for that stall but does not happen
I did do my injectors previously, 91K as my car is an 2015 and i was getting the injector code, did coil at that time also.
good luck
Just wanted to update my situation in case anyone else stumbles here in the future with the same problems:
The dealer was in touch with Honda Tech Line throughout the process, and they were confident that the valves being out of adjustment at my milage was the cause. I knew they needed to be done, but they showed no signs of being the cause of the random engine shut off or code. Since it was essentially deferred maintenance, I told them to go ahead with the adjustment knowing the issue would persist. Sure enough, the Fit was having the same issue with the same codes as before.
After a month of waiting, the new PCM finally came in and the relays I requested are still backordered.
Edit - and the code is back with the same random stall problem 50 miles after picking it up. If the new relays don't do the trick once they come in, I think it will be time to move onto another car. Problem does not appear to be mechanical, new PCM didn't help; relays and wiring are the only things left that I can think of.
The dealer was in touch with Honda Tech Line throughout the process, and they were confident that the valves being out of adjustment at my milage was the cause. I knew they needed to be done, but they showed no signs of being the cause of the random engine shut off or code. Since it was essentially deferred maintenance, I told them to go ahead with the adjustment knowing the issue would persist. Sure enough, the Fit was having the same issue with the same codes as before.
After a month of waiting, the new PCM finally came in and the relays I requested are still backordered.
Edit - and the code is back with the same random stall problem 50 miles after picking it up. If the new relays don't do the trick once they come in, I think it will be time to move onto another car. Problem does not appear to be mechanical, new PCM didn't help; relays and wiring are the only things left that I can think of.
Last edited by GXOR; Jul 31, 2021 at 11:40 PM.


