Hi everyone,
New to the sight and back in a 20005 Accord after 25yrs away.So far im loving the car but it did come with a few issues.Whats giving me grief is mil code p2185.This mil comes back immediately on restart
After researching this code it would appear that it's the ECT on the left lower rad(ECT high)I have also found that the ECM program may need an up date with this code?According to the manual the sensor should be tested.However as and industrial electrician I don't trust testing this PID (proportional integral differential)sensor since it cannot done across it's entire range.I would rather replace the sensor and have an independent do it instead of at Honda's rate.
Again as an industrial electrician I find the need for a ECM update to be a little strange since this is how we try to hide faults/fool the ECM by substituting parameters.
The manual says to test the sensor and "update" the program if it tests good.It also says to replace the ECM if the update does not work.It would appear that the point of this whole exorcise is to simply turn off the mil since the ECM would likely recognize the ECT as bad and remove it from reference anyway leaving the mil on without the reflash.Replacing the ECM in the event that the mil stays lit makes me think this peripheral is just a fine tuning PID for fuel savings.If this is true I would be very upset to have to spend the money on a new ECM just to shut off a light
The car currently passes the e-test with flying colors but the inspectors **** and moan about the mil every time.Everyone agrees that it does not run as if it's in a limp mode.In fact it runs better than the other 2005 Accords i have test driven
The questions i have are as follows
1)How much coolant is there in the system as i would rather change it all since a good portion is getting dumped anyway
2)Is Honda coolant a must or can any type be substituted it sounds like it is required as i believe this mil issue has to do to system/coolant properties and age.If honda says that their coolant must be used it would be very telling
3)How common is it to need the ECM update.
Thanks

 

See link:

ECT Sensor 2

 

Ok, let's just go with thermistor for the DIY'ers here Reflashing the PCM is not uncommon, i'd slap in a new sensor and see what happens first. Honda recommends their coolant of course, it's a 50/50 mix no water needed, capacity is as follows:
At Coolant Change:
M/T:
5.1 L (1.35 US gal)
A/T:
5.0 L (1.32 US gal)

Any good quality 50/50 mix coolant will be fine, Peak has a good one.

It may not be running in limp mode, but depending on the sensor readings it's probably not in closed loop operation. Or, get this, it's in closed loop all the time neither is good, you should address the problem...but you're an electrical engineer, so you knew that already
let us know what happens.

 

good article redbull

 

I was already back from picking up the part before I thought about using Honda specific coolant.I agree that leaving the issue unattended for long is not a good idea.Thanks for the link and capacities.The sensor was $38,thats cheap here in Canada