Hello all 8th civic users,

I would like to get some help on my car that is failing more and more to start along time.
I've read a lot of stuff, articles, posts on forum about things around my issue, done the tests I could too, but still not resolved.
I hope someone here could give me a better analysis than mine or at least some tracks to follow.
I'll try to explain the more clearly possible what happens.

When the car is not starting, dashboard is displaying message "check system" below a sequence of several aspects : VSA, ABS, engine icon. Pressing the start button will just crank but not launch engine.
From the moment it happens, I can pass various time (10 min to 3 hours for the worst day) doing continually ignition OFF and ON, until a "normal" ignition event occurs and have finally the possibility to get the engine running. In that case, all messages disappear and i see the green key icon flashing half a second.

The issue started end of winter, rarely, and then it gained more and more frequency until summer.
The facts are :

• I never have this problem when I take my car from the garage, after some days of non use.
• I systematically have this problem when I drive for 2 hours, let my car under the sun for the day and try to take it end of the afternoon.

When I started to question, I supposed it was linked to the heat ... and by the way I noticed it made a long time I didn't heard the radiator fan going gone a little after I stop driving.
The car has absolutely no issue when it's driven, good performances, no heating, ...
One detail that made me look closer to the radiator fan is because I first thought to a heat problem and also, the climatisation isn't working anymore since more or less the same period the not starting issue begun.

What I've done :

• provoked the issue to pass time with my car in this state, looking for some hints, but mostly confirm I can't see anymore the radiator fan running when I stop driving. Pretty sure it was often before ...
• tested all the fuses I could and all seems ok
• done a test in my garage that is at the center of my mind today : launch the engine for 2 minutes after arriving, then Ignition OFF, wait for 2 minutes, then Ignition ON : issue happens, error messages and fail start, but in that case I usually have to trick the ignition for a short time, less than 5 minutes, before being able to launch the engine again. So this makes me doubt heating relative problem, as the engine has not the time to go warm in 2 minutes. Other fact : If I start the engine for 2 minutes, I cut, and a do Ignition ON in the 30 seconds following, I don't have the issue ... So it seems around one minute after I cut the engine, something is happening in the car preventing to have a normal behavior at the next ignition.
• connected a OBD-2 diagnostic system, that gave me some DTC codes P0602 : Engine control module (ECM) - programming error - temporary and confirmed
• connected a J2534 device to be able to use Honda diagnostic tool and get some other codes that I attach as images.
• tried an update of the ECU firmware but the car is already with the last one existing
• cleaned battery connections and made it stronger
• tested the radiator fan relay from Honda diagnostic tool and get it spin

I've read a lot of people that changed their ECU but I can't resolve to it as it is working perfectly during driving session.
What I observed is I can't communicate with the ECU trough the different protocols (OBD-2, ...) when I've the problem .. so I think it's because the ECU don't communicate I've this issue and I still search why.

Hope someone can see something in all of it !

 

hi did you manage to resolve this issue please

 

Yes. I removed the glove box to disconnect and extract the EMU. I've sent the beast to a company that offers service in the case of error codes I had. After à diag they confirmed it was the "usual" issue, repaired, sent it back, and no more issue at all after remount.