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What is the air differential temps on your car ? (outside air temp vs temp at vents) ? That would tell you how well the system is operating.

The low pressure at 50 (idle i assume) is ok. The 200 on the high side could be a little low. (what is it at 2000 rpm ? )
 

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What is the air differential temps on your car ? (outside air temp vs temp at vents) ? That would tell you how well the system is operating.

The low pressure at 50 (idle i assume) is ok. The 200 on the high side could be a little low. (what is it at 2000 rpm ? )
thanks for attention and correct extra questions.
I have collected few inspirational images today.
here we go...

Air differential Temperatures inside, outside and interior surface temperature.
26 May, 1 PM.
45 degrees Celcius outside (113 Farenheit),
surface of dashboard is 191 farenheit (88 deg C).
CAR interior.jpg


The temperature of AC system's cooled air while engine is still cold (coolant T< 80 deg).
air is 122 Farenheit (+50 deg Celcius) within first 3-5 minutes after engine is started (AC clutch is ON but cooling Fan of condenser is OFF)
AC system performance engine is cold.jpg


The AC system performance after 30 min driving on high way, System is in MANUAL, setting point LO and AC cabin blower is on maximum.
air temperature charged into Cabin is 72 Farenheit (+ 23 degrees C). Outside is still about 40. NB: only LOW speed of condenser cooling fan is engaged / ON.
AC performance engine is hot.jpg


QUESTION: what is the AC compressor suction / discharge pressures at 2000 RPM.
Test Stand Unit is connected, 2000 RPM are kept, Bi-directional scanner shows 5V signal for adjustable WOBBLE disc position which is 100% Compressor capacity.
suction 14 Bar (55-60 PSI)
discharge is 16 BAR (255 PSI)
all is very close to Cadillac SRX Factory settings / initial parameters.
22 degrees C (72 farenheit) is an air charged into Cabin.
AC compressor at engine RPM 2000.jpg
 

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Yes, based on what i know about the ac systems in general I think you are right at the design specs for working as designed. I don't believe that Cadillac made any modifications for outside the USA market (meaning hotter climates) for extra cooling capacity. If that is the case and you need more capacity cooling I'd suggest talking to some of the local ac service shops in the area. They might know of some suggestions to get the air cooler in the vehicle through modifications they have come up with to assist in cooling vehicles interiors (people don't like being hot). Also, if you haven't figured out your problems with the cooling fans I'd pursue that angle as well since cooling efficiency is needed as well and if your fans aren't working as intended then you can benefit from correcting that as well. But overall the bottom line is that your temperature differentials from the outside hot air and air coming out of the vents is about 40 - 50 degrees. That's a good working ac system in any climate.
 

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I had opportunity to use Bi-directional scanner today to see common picture around Car cooling Fan, compressor adjustable ratio and running Ac system pressures.

at OFF condition the system charge is at 10.5 Bar (145 psi) which is about 46 deg dew/boiling point for R134A. simialr 40-45 deg were outside and I assume I haven't non-condensable gases (air) in my AC circuit.
AC system OFF equalized charge pressure.jpg


AC with running compressor keeps 4 Bar suction and 14 Bar discharge. condenser cooling Fan is on LOW speed still... Compressor Wobble disc is at maximum capacity (signal 5 V is applied)
Magic is that Bi-directional scanner shows Fan 2 & # are OFF. only Fan # 1 is ON... cooling fan of condenser is running on LOW speed only depsite of AC clutch is ON and engine runs.
Air in Cabin (from deflectors) is about + 20 deg... Should be + 6, + 9 deg, at least. Suction piping of refrigerant (under the motor hood) is not sweating at all.
AC system READ OUT parameters _2.jpg


AC system READ OUT parameters 1.jpg


extra R&D:
manually I can start Fan MEDIUM and FAN MAX speed! it works!
that means all wirings, connectors, slots, relays , harness plate soldering, etc. are VERY MUCH OK!!!!!!!!
the trouble is somewhere inside ECU brains.. I still can't understand why ECU do not generate signal to start cooling Fan on a MEDIUM speed once AC clutch is ON. this should be done by default at any engine coolant T!

please look on CABIN's Air Vents temperature once condenser cooling fan is enforced to run on MEDIUM speed.
air is lowered down to 45 Farenheit (7.5 degrees celcius) !!!!!!!!!!!
AC Fan RUN charged air farenheit.jpg


presently I do still have doubts in:
1. if solenoid 0-5V control valve for AC compressor capacity adjustment does really respond well on to 0-5V signal. it is USD 35 item. shall replace to see what would be wrong there (if any).
2. if ECU of engine does really have a proper mind set for Cooling Fans control. I do not really know where to go to get it solved. should i take second hand ECU and try to run my caddy with ... ?

I'm getting really disappointed with all electronic surprises my 7 yrs old SRX brings on a daily basis ... (cruise control if off, remote start is off, cooling fans control is off, CUE is regularly frozen, Immobilizer has own opinion every 28 days, rear seats heating impossible to control and fuse to be kept out, etc. ...)
 

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Yes, based on what i know about the ac systems in general I think you are right at the design specs for working as designed. I don't believe that Cadillac made any modifications for outside the USA market (meaning hotter climates) for extra cooling capacity. If that is the case and you need more capacity cooling I'd suggest talking to some of the local ac service shops in the area. They might know of some suggestions to get the air cooler in the vehicle through modifications they have come up with to assist in cooling vehicles interiors (people don't like being hot). Also, if you haven't figured out your problems with the cooling fans I'd pursue that angle as well since cooling efficiency is needed as well and if your fans aren't working as intended then you can benefit from correcting that as well. But overall the bottom line is that your temperature differentials from the outside hot air and air coming out of the vents is about 40 - 50 degrees. That's a good working ac system in any climate.
thanks.

re: good AC working system examples.

my HONDA CRV (2015) runs well up to +51 deg outside. hands are frozen to the steering wheel. Honda is sold.
my SUBARU FORESTER runs super well within same environment. Subaru went to my girl-friend
my JAGUAR E-PACE (just purchased 3 months ago) runs as Paradise . just adjust +22 deg C inside and drive, nothing else you need to worry about! E-PACE is for my wife.
my office car Pajero I tortured over 65k miles (2.5 yrs) with no regrets and its AC run super powerful!. Pajero went to next rider.

I chose SRX and I'm dyeing almost 2 yrs to get it aligned with normal human climatic needs. and it is GCC version - adopted for Arabian desert climate by Maker.
 

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AHA ! There it is. Adapted for Arabian desert by Maker. Who is Maker and what did they do to your Cadillac ? That would be my first question. If they have changed the computer programming you might want to use the scan tool to get the firmware and software versions of your ECU and CCU control programming. And then try and figure out if that's different somehow or if Maker has done something to it all. Possibly screwed up the programming.
 

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AHA ! There it is. Adapted for Arabian desert by Maker. Who is Maker and what did they do to your Cadillac ? That would be my first question. If they have changed the computer programming you might want to use the scan tool to get the firmware and software versions of your ECU and CCU control programming. And then try and figure out if that's different somehow or if Maker has done something to it all. Possibly screwed up the programming.
story is continued.
as I could not repair and / or bypass control circuit I made a power circuit modification. My High speed Fan has never been activated by control since I bought this Caddy. for Medium Speed Fan's resistor the thick jumper was installed to see if increased fan speed solves the inefficiency of AC at + 48 deg environment.
wow! I have now + 7 deg air charged into cabin and I have my AC run now as a super freezer!

the core AC low efficiency reason is found - the Cooling fan medium speed is not absolutely enough and High Speed only shall be considered.
 

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I had opportunity to use Bi-directional scanner today to see common picture around Car cooling Fan, compressor adjustable ratio and running Ac system pressures.

AC with running compressor keeps 4 Bar suction and 14 Bar discharge. condenser cooling Fan is on LOW speed still... Compressor Wobble disc is at maximum capacity (signal 5 V is applied)
Magic is that Bi-directional scanner shows Fan 2 & # are OFF. only Fan # 1 is ON... cooling fan of condenser is running on LOW speed only depsite of AC clutch is ON and engine runs.
Air in Cabin (from deflectors) is about + 20 deg... Should be + 6, + 9 deg, at least. Suction piping of refrigerant (under the motor hood) is not sweating at all.
Harness plate for all relays and fuses was disassembled and core of malfunctions seems found.
photo is below.
we have extra 9 relays hidden beneaf Printed circuit Board... those are partially visible on electric scheme and it is hard to identify them as no marking and no numbering is with me.
the copper road to one of Medium /High Speed control pin is burnt and also at elast 2 relays here are responsible for activating of High/Low control circuits once ECU signal is sent.

presently I'm looking for spare one. GMC spares seller(s) have replied it is not something they faced as needed over last 5 yrs... I could not gain anything clear on what shall be procured as Price is USD 350 / set and waiting time 35 working days... plus I can see on printed offer it is 2009 version.. I'm very much confused.
checked salvage Yard offers and even more complicated picture was found...
Printed circuit board for SRX 2010, 2014 different modifications the Part # is the same, however looks different (different amount of internal relays are seen there). The circuit Board # is 13847014_01 for all Versions of SRX...2010-2014...
The Harness Plate ASSEMBLY itself has a GMC Part # 812461952 6B (my SRX 2014, premium with HID), the version 5B is same SRX 2014 but without HID and the version 1B is SRX 2010 (most probably)...
Harness plate old damages.jpg


for those who willing to disassemble same Harness assembly in future please prepare tooth picks... there are dozen clips which should be released simultaneously to pull up the Harness plate cover. see it for wrong version 5B... that Printed circuit Board has remained my Caddy withiout HID LO/High... :cool: I still need to find out precisely 6B version of Harness Plate assembly.
harness plate disassembling method.jpg
 

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I found second hand Harness Plate with same precisely Harness assembly Part number and modification 6B.
Printed circuit Board was taken out today and installed into existing Harness plate housing.

results:
1. Alarm "Service Vehicle soon" gone.
2. Auto-Head Lights ON/OFF is not operating at all. Manually LO/HIGH HID are working well. Light Sensor on dash panel covering / uncovering do not initiate automatic HID ON/OFF... it is quite out of logic as sensor is connected to Body control Module and I did not touch it all during Harness plate renewal...
3. cooling Fan only LOW speed is activating and MEDIUM and HIGH - never... again same story as I'm facing since SEP 2019..
4. Cooling Fan is OFF unless engine coolant temp < 80 deg. even if ACc clutch is engaged the cooling Fan and condenser are remained dead while engine is still cold... Same story as I had before.

everything run now without Alerting messages (Cadillac SRX is happy) but situation is same as before:
no AC at all while engine is cold
super weak AC while riding

I'm fed up with all those surprises, symptoms, etc...
no force to fight anymore. it is endless nightmare .

Suppose I need again to find our professional bi-directional scanner and see if all fan's SPEEDS could be ON/OFF manually via ECU. if yes - the reason is in ECU only as rest of hardware already replaced...
 

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Yep, and need to follow the wiring to the sources. Check the connections as testing to see where the control voltages drop out at. That burnt trace on the board isn't good though. That indicates too much current was drawn. AS a result something else is probably fried too from it. You "fixed" the problem you found but not the actual source of your current issue. And it does sound like the Control ECu could be suspect. And though. Guessing is not a good idea for repairs. Testing the actual circuit and voltages is the only real way to go on it.
 
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