[Lotustalk_lacy]

I've purchased a branded standalone ECU recently and has been trying to get it to work. My tuner has been facing some strange problem trying to setup the basic before going up to the dyno, again.

Both of us have been very busy, it has been a month since, we've not gotten anywhere. Last saturday, we got together and did some testing following the recommendation of the manufacturer. The strange issues persisted. We reverted back to stock ECU (pnp) so I can drive the car home and I realised the AC is no longer cold.

Dropped my car at workshop today and was informed that the Compressor was blown with oil leaking and also the AC pipe in the front condensor had also bursted. Then I realised that while troubleshooting the strange ECU issue, we saw the rear hatch had smoke/steam coming out from the pulley side, now we know what it is. When the smk came, it was 100C oil and water. Well, this is definately within threshold as I've seen up to 110c oil and 115c water in track.

So now I am wondering if there could be a problem with the standalone ECU or wiring harness that caused the compressor and pipe to burst? Well, I know it sounds strange, ECU, Wiring and compressor/pipe burst. But the ECU is really behaving strangely.

I remember reading somewhere about some different between US wiring and Euro wiring. Anyone has specific or can direct me to some reading materials? I've been searching.

I am not looking to bury anyone, just want to avoid blowing another compressor and get my ecu to work properly. My tuner is professional and has tuned more than thousand of cars. My previous ride was tuned by him as well.

I dont wish to name the ECU to avoid misunderstanding. I just want to solve my problem and go on to my next mod Seq dogbox. :sad:

Any help will be much appreciated.

 

[Deja Vu]

Without knowing which ECU you have it'll make things a bit difficult to diagnose. The reason being some of them leave A/C control up to the stock ECU.

As for what could cause your problem, aside from it just being a coincidence, would be the ECU locking the clutch on the compressor, while ignoring the high pressure signal telling it to unlock, and then doing a bunch of high RPM dyno runs.

In that case you'd need to go to whatever the ECU's A/C config is and make sure it's setup to properly disengage the clutch when it doesn't have a signal for the A/C being on (I can't imagine you were making these runs with the A/C on intentionally), and that it also cuts out when it detects high and low pressure.

 

[Lotustalk_lacy]

The standalone disconnects the oem ecu entirely. So the standalone controls the AC.

Yes, my mech suspects the same as what u are saying about the compressor.

Anyway, we were not doing high rpm runs, we were trying to troubleshooting some strangle issue with the ecu. RPM was most of the time at idle or 3-4k. But we were doing it for a good 1-2 hours with little break in between.

Without knowing which ECU you have it'll make things a bit difficult to diagnose. The reason being some of them leave A/C control up to the stock ECU.

As for what could cause your problem, aside from it just being a coincidence, would be the ECU locking the clutch on the compressor, while ignoring the high pressure signal telling it to unlock, and then doing a bunch of high RPM dyno runs.

In that case you'd need to go to whatever the ECU's A/C config is and make sure it's setup to properly disengage the clutch when it doesn't have a signal for the A/C being on (I can't imagine you were making these runs with the A/C on intentionally), and that it also cuts out when it detects high and low pressure.

 

[Lotustalk_lacy]

Also, my car has custom rely to perm fix the persistence fan module failure issue. Not sure if it has thing to do with it... but I've been running on these custom rely for months.

Maybe the standalone requires the fan control module to work properly?

 

[Deja Vu]

That relay module has a relay for the compressor as well from what I remember. If there's something wrong with it's wiring or the relay jammed closed then the compressor clutch would remain engaged. Over time that would really screw up your a/c system (burnt out compressor, blown lines from overpressure etc)

Your standalone also has to read the input of the trinary switch to determine if it is safe to engage the compressor clutch.