2006+ Honda Civic Forum banner

updated air-con compressor relay to prevent failure

AC/Heater 
392K views 643 replies 222 participants last post by  culzean 
#1 · (Edited)
This is a common cause of failure of the A/C on our civics.

In fact just a week ago Honda issued a Bulletin about it. The original fit Omron relay is suseptable to moisture ingress. This can form nitric acid in the presence of the normal arcing as the contacts operate. This will lead to corrosion and eventual failure. The Bulletin warns that the relay can fail either open or short circuit. If the latter this forces the compressor on to 100% duty cycle and can burn it out.
The remedy is a replacement relay from a different manufacturer - Mitsuba - that is a better quality item. The bulletin warns that the EPC is not yet updated, so you have to order this countermeasure part number directly to recieve the new part, otherwise you will just get the "old" part. I'm surprised they are not doing a campain over this considering if can fail in a way that might lead to screwing up other parts of your aircon

This the bulletin number:-

SM-10-002-00

It affects ALL civics (and CR-V and jazz) upto and including 2011 model year

Here is the countermeasure part number:-

39794-SDA-A05

RELAY ASSY., POWER (MICRO ISO) (MITSUBA)



The datasheet for the original Omron part is here:






The specific part is G8HL-H71 which appears to be a Honda specific version not listed on Omron's website - the standard relay is 180ohm and the Honda version is 120ohm coil resistance.​


The Mitsuba part seems to already be used on other Hondas. I found this link for example​


 
See less See more
#42 ·
Have you tried the Battery Disconnect / ECU Reset yet ?
 
#46 ·
Firstly, thank you for the useful information.

When i had a problem with my a/c last summer, the problem found on a faulty high-pressure a/c valve on the a/c system under the front hood. As i did not use the a/c for months, the liquid stack on the valve. So, the valve could not work properly.

It was replaced with no extra charge as my car was on its guarantee.

Please, contact your local Honda dealer to check it ;)
 
#52 · (Edited)
My relay came today from the link I posted from toolbox
I'll keep you posted (my air con does work but wanted one as a back up)
It should be fine as the pin numbers and wiring diagrams match perfectly the Omron link from first post
 
#55 ·
I've bought an Omron version ...

I'm a firm believer in "preventive maintenance", when it comes to the sort of small things that can ruin your whole day ...

My Mitsuba version is working fine, but I'm going to change it just the same ...
 
  • Like
Reactions: Rixy
#60 ·
I tried mine today no error messages, but sadly the air con pully did not engage when set on LO. I put Omron back in and it did. So it would appear the rely is not suitable, why I dont know. :confused: Only £4 worth a try I suppose :(
 
  • Like
Reactions: Ranjbali
#61 ·
I tried mine today no error messages, but sadly the air con pulley did not engage when set on LO. I put Omron back in and it did. So it would appear the relay is not suitable, why I don't know. :confused: Only £4 worth a try I suppose :(
To be honest, a somewhat predictable outcome - and even if had worked, there is always a risk that cheap dodgy (chinese knock-off ?) electrical components could cause a fire - try telling your insurer that you fitted a part of "unknown provenance" !!!
 
#63 ·
Fitted the Mitsuba relay today, (dealer actually had item I needed in stock for a change :eek:). Like others have said, the old relay was hard to shift by hand, I had to get the swan neck pliers out, with a piece of cloth on the jaws, to ease it out. All good, and thanks for the info on this, I would never have known otherwise. :D
 
#65 ·
I have no plans to use my car this evening(been drinking so couldnt even if i wanted to), so as suggested im going to disconnect the battery earth lead and will leave it off all night.
I dont hold out much hope of it curing my A/C problem, but i hope everything else still works ok when i reconnect it. :)
 
#66 · (Edited)
Well.......my clock time and fuel computer records had been lost when i reconnected the battery, but unfortunately no difference to my air con - it still doesnt work.
Thats it then....game over. I have resigned myself to the air con never again working while i still own this car. :(
Was a very welcome feature on the relatively few occasions that i used it, but at least the car still runs fine without it.
 
#67 ·
Ah-ha

I didn't realise you were in the habit of not using the AC regularly

The recommendation - and my practice - is to have it on all or most of the time

Otherwise you are prone to mechanical / compressor failure

Take the car to a vehicle AC specialist, and get a diagnosis

If it's the compressor etc., then buy one on eBay or from a Breaker, or get the specialist to refurbish the existing unit

Then, leave it ON all the time !!!

p.s. - you did check the AC fuse(s) ?
 
#71 ·
I've checked my fuses too, but they seem ok too.

In regards to using the A/C all the time, well I never did with my prevoius car's as I don't want to waste fuel. So was only used in the hot summer months.

Didn't realise you could use the A/c for heating, what difference does it make ?
 
#79 ·
Think i may have this prob mine just stopped all of a sudden no leaks radiator looks ok took the relay out and it looks mint, i take it they get moisture in somehow

Sent from my GT-I9300 using Tapatalk 2
 
#81 · (Edited)
Changed relay today - AC works fine again. According to a service I visited for checking/filling system, I should change compressor. The did not bother to give a direct + to compressor. It is Sweden... That's how they work and get big money. Dealer suggested realay immediatly. Thanks to them and forum.
 
#82 ·
On Saturday I was quoted £550 to have a new compressor fitted - my air-con stopped working over the winter and I paid to have it regassed to no avail!
Having just read this thread I've taken the relay out, tapped it, put it back in and the aircon is working again.
Civinfo - I love you!!!
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top