Rep Power: 0

Finally HAVE to address CEL in my sweeties 2006 Civic. You cant have a CEL and pass e-check!

0111 and another one for the coolant sensor have been a problem for some time. My research has found that its typically from the coolant sensor getting corroded and not making contact. The contact is fine. That was the past and light did go away on its own for a while but came back.

Now its time for some heavy duty diagnostics. Using a scanner, we have checked the intake temp reported to the ECU. 1st test at RT showed right temp. Some warming up to 80° showed it was working, but on a repeat, it STUCK at 80 and didnt return to RT. Weird, but I will disassemble the MAF if I can and see if its a bad solder joint.

Next stupid PITA- AC was not working right, even after the clutch was replaced. (there is a thread from last summer on that job) Since the scanner was hooked, we did some testing for AC components. Fans come on, when the scanner tells them to. AC clutch comes on when told, BUT fans and clutch will also come on by themselves EVEN THOUGH the AC switch isnt on!

I'm going to guess a faulty AC computer for that.

Any comments or answers are welcome in solving these problems for good. I've found good info on these boards in the past because most problems are experienced by many and solutions have been found.

TIA,

-SP

 
Rep Power: 518

Maybe....P0128?
No it isn't. It's time for a bulletin search.

http://ww2.justanswer.com/uploads/Ho...201805_hyb.pdf

Fix the coolant temp sensor #2 first.
It's the one in the bottom tank of the radiator. (Did you mess with this one or the other one?)
If you already messed with the wiring, then replace the sensor itself.
Please use factory parts.


They run AC in defrost mode too without lighting the AC indicator.

A good scanner should show the AC REQUEST and AC CLUTCH RELAY pids in a datalist.
If your scanner can do bidirectional controls on the AC, does it have those pids in the datalist?

 
Rep Power: 0

Yes, I found the info in the bulletin earlier this year. I removed the connector and it was good with no corrosion.

Fast forward to now- CEL troubles are fixed. Heres what we eventually found. Maf sensor didnt read temp right. It was replaced. Temps read correctly now. Coolant sensor was rechecked and THIS TIME one of the pins pulled free from the sensor. New sensor time! All is well with the engine.

I know about the AC cycling with defrost function. That wasnt the case. Thanks for the tip on the AC clutch. We'll narrow down some of the silliness when things arent so busy at the dealer where my boy works.

-SP