I have a 2012 Jazz hybrid. My AC stopped working so I bought the 4 pin relay 39794 sda A05. The jazz manual shows an under battery relay box holding 3 relays, but when I opened it, I see there are only two relays: the A05 (which I replaced), and, a 5 pin Mitsuba RC-5102. My fans go on, but my AC is not working!

Q1: was the A05 also for my compressor? If so, my compressor may be shot...
Q2: I cannot find what the RC-5102 relay is for. Is this possibly my compressor relay? Or, what other systems does it control?

Any info greatly appreciated!

 

That 5 pin controls the starter I believe. I've got a USDM non-hybrid fit so I can't help tell you if its your relay or compressor.

 

Thank you red05. Despite the fact that all resources I've come across say the 3-relay box for: radiator fan, condenser fan, AC clutch, is under the battery (or behind headlight), it turns out that MY 3-relay box is under the windshield washer reservoir! So, I'm going to try to replace the presumed AC clutch relay (A05) in that box. I'll let you know if that does the trick...

 

had the same issue (USDM) and replaced everything under the head light...now i'm breathing smoke its so cold.

 

Thanks, csingham. I guess I spoke too soon: I replaced all three relays, my fans came on and my compressor clicked, but it was barely blowing cold air. I went to have it filled and it did not get very cold after that I thought maybe the seals just needed to get the oil circulated, but that was not correct. within a couple of hours it was blowing warm. I went back and now my fans seem to be working very intermittently and the air conditioning is definitely not working! the so-called technician did not seem to know whether it was a condenser blockage or a high or low pressure switch. His fancy equipment did read very high high side pressures, instead of being 250 it was up to 400 so I thought that indicates a blockage or a pressure switch problem, but he was unsure. if anyone has more advice on this I'd love to know! if it's the evaporator sensor I understand that's a real bear to get out because you have to take off the blower motor and many parts under the dash.

 

For vehicles currently running with freon R-134a only
Outside-----low side-------High side------Center vent temp
60 F -----28-38 psi----130-190 psi ----44-46 F
70 F ------30-40 psi ---190-220 psi ----44-48 F
80 F ------30-40 psi ---190-220 psi ----43-48 F
90 F ------35-40 psi ---190-225 psi ----44-50 F
100 F -----40-50 psi ---200-250 psi ----52-60 F
110 F -----50-60 psi ---250-300 psi ----68-74 F
120 F -----55-65 psi ---320-350 psi ----70-75 F

 

Thanks fit09. Thi is very helpful. Now I just have to figure out why NEITHER fan is going on-despite new relays-when i push the AC button! 😠

 

Just so I understand earlier you had mentioned the two fans both condenser and radiator fans where cycling on and off. The compressor clutch was cycling on and off quickly as well. Correct ? If the mechanic did in fact read 400 psi on the high side you have a blockage as you mentioned earlier. What was the low side pressure at that time ? Have you added refrigerant recently? Overcharged system can also give the pressures that you are having. If you have that high of a head pressure then the compressor is cycling on/off by the high pressure switch.
The drier/receiver on the condenser might have failed thus sending particles thru your condenser and perhaps to your expansion valve. Very low or vacuum pressure on the low side is a sign of this issue. Hope this helps a little.

 

Hi fit09. Yesterday, I tried cleaning my condenser fins with a foam cleaner and a hose. Because it was very difficult to get the plastic pop fasteners off of the underside of the bumper cover, I could only get the top and sides unfastened and reached in to the front of the condenser. I don't think I got much of the lower portion hosed. Today, I pushed the AC button, and neither fan goes on. It is hard for me to see whether the compressor is running, but I don't think so. I tested the fuses and they all seem to have continuity.

So, I have 3 new relays, working fuses, but no fan action! To answer your low side pressure question, the tech showed me it read about 30. The high high-side pressures also lead me to believe that I have: (a) a blocked condenser, (b) a bad [high?] pressure sensor, or, (c) a bad TXV thermister valve—which I hope isn't the case because I understand it is a bear to get out requiring dismantling of the blower motor assembly etc. By process of elimination (yes, I guess that means 'throwing parts' at a problem) I thought I would unplug what I believe is the pressure sensor, short the wire connector, and see if it triggers the system to come on. Is the sensor the one on a very narrow alum tube voming off the evaporator and down to bottom of front condenser? Or, is that a low pressure sensor? Is it correct that the system has botb? Thank you VERY much for your help!

 

I looked back thru some of your earlier posts and you mentioned that you had refrigerant added. Not sure how the mechanic did this but it's best IMO to first reclaim the refrigerant, vacuum for at least 30 mins, verify vacuum holds (no leaks) and recharge by either weighing the charge with a digital scale or using a high end machine that can measure the charge. That might be one issue.
Do a quick check of your radiator and condenser fans by disconnecting the wires at the snap connectors, then run wires from positive and negative terms of battery to each fan to verify that they indeed are working.
If you replaced the two fan relays and compressor relay you should be good and rule out those. You would need to troubleshoot upstream of those for power perhaps.
Just to clarify a little the TXV is a valve and separate from the evaporator temp switch mounted on the face of the evaporator. I doubt this is your issue given what you have described. Normally the evap ices over during long trips if that fails.
The Fit only has a high pressure switch and the location you described is correct.
I am just a DIYer and not an AC expert, but I have worked on my Fit AC and other cars in the past so that's the best I provide at this time.

 

As Alice might put it: curiouser and curiouser:

RELAYS: Replaced all 3 relays, compressor, AC fan, radiator fan.
COMPRESSOR: Definitely going on when I push AC button on dash, and runs while AC on.
FANS: **Now they do NOT come on with AC! But, if I push AC button a couple of times, they BOTH spin MOMENTARILY and then stop!!
AC CONDENSER FAN SENSOR (ECT #2?): I disconnected the plug at bottom left fan and jumped the wires. AC pushed on. NO spinning.
AC PRESSURE SWITCH/SENSOR: On the narrow line running from evap down to bottom of condenser--cannot reach it either from top, or from bottom with bottom shield/panel off. May have to jack up car. Any advise on reaching this? [I do suspect this MIGHT be the culprit.]
ENGINE COOLANT TEMP SENSOR (ECT #1?): I see TWO 3-pin sensors sitting right next to each other to the right of spark plug number 4. (See PIC) But I don't know why there are two of them, nor, which is the ECT, nor which of the 3 pins to jump! Any advice on this??

I can't seem to find any info on cause of 'both fans spin momentarily.' Aside from the ECTs, or, the AC pressure switch, what else might control them?? Dreaded TXV valve? Hope not. An overcharge, or, leak? (Recently filled as noted earlier, and, high side, very high!) I ruled out a bad dash button bc I figured if it was bad, then the compressor would not go on either! (Unless there are multiple contacts in it.)Thanks!!

 

Refer to this video for troubleshooting your AC. This is not Fit, but similar in how it works and with a 2 pin high pressure switch. You will need a millimeter to preform these tests. My high pressure switch on my 09 Fit is on passenger side near condenser just off to the side and down low. Wiring connection is accessible from top of car. Not sure about your 2012 hybrid layout in this respect.

 

Skipped over this thread because of the name. "Oh, a question about a relay location" I thought. Ha. If only, eh?
Unfortunately can't dive into troubleshooting with you at this time as much as I'd like to, but I can provide documents regarding the systems. Did do a quick check for fans not operating, A/C on. The result being that you should have a DTC, diagnostic troubleshooting code. OR that there was some buggery of the wiring. That doesn't sit right after skim/reading your efforts here.

Lets start you off with some general files. Please forgive if not all of these are useful. cant think tonight but uh. give the expansion valve bit some consideration.
Heres a site with a system descrip. if you didn't already talk about this and I missed it. https://www.yourmechanic.com/article...e-orifice-tube

There was a gent a few months back whose issues were traced back to that component's failure.. food for thought.

 

Thank you fit09 and pyts. The pdf files look especially helpful. Q: Does the schematic apply to the GP1 version of Jazz? (That's what I have.) Also, I'll try to take pic of my dash controls as I believe mine (2012) uses a 'climate control' system, i.e.it has a round button combo of: AUTO, FAN ON-OFF, FAN UP-DOWN, and a second round button for: A/C, MODE, COOLER-HOTTER. The 'outside air in' and 'recirculate' buttons are in a horizontal row just offset from the blue screen round digital display.

Does the schematic you provided go along with that set up?

And, as a True Confession: Although I have owned a Multimeter for a few years, I confess that I have really only used it to check continuity, and....whether or not there is any life in my DC batteries. (I know, it's like the guy who owns a set of golf clubs but only keeps them on hand in case a burglar breaks in.) Anyway, I guess my long-procrastinated Multimeter tutorial lessons are ripe for delving into now!

Regards,
Jeff

 

I'm only familiar with USDM vehicles and only possess the service manual for the USDM fit, so if something aint the same I dont know what to tell you. If I were honda I would want as few dissimilarities as possible between regions to help reduce production costs. It sounds like your A/C system is already drastically different, still a picture would be beneficial. I *may* have a wiring diagram for the canadian model.. not sure if that'll come in handy.

Were you able to read the article on the orifice tube/expansion valve? I think it sounded inline with your original fault.

Oh and as for the multimeter, worry not. Youll likely be wrapping a bare paperclip, one on each prong of the multimeter to make them fit into the little connector pin holes that you'll be testing. Its not different from testing for continuity. You just need the 12v D/C (direct current) setting since thats what cars run on.. unless that too is different elsewhere. And. Ohms.

 

So we all know that I had very high readings on the high pressure side; we also know that that generally indicates a blockage of some sort. My question is: would that blockage be at the TXV valve on the evaporator as pyts suspects? Or might it be on the receiver drier? Or on the whole condenser itself internally? In any event because some sources indicated that there might be a leak of refrigerant I hooked up a dye can to the low pressure side and after only a minute or two I hear rattle-hiss-pop- spray and apparently my high pressure relief valve on the back of the compressor (the opposite of the pulley side) blew and oil went all over the lower plastic pan of the engine. So now in addition to needing to know WHERE my blockage is (txv, dryer, condenser...), I am also trying to determine whether the high pressure relief valve on the compressor can be (a) reused, (b) simply be replaced, or (c) do I have to replace my whole compressor? Any other reply to this latest part of the Saga greatly appreciated! Thx.