Denso ES27C AC Compressor control (Toyota/Lexus)
Re: Denso ES27C AC Compressor control (Toyota/Lexus)
Hi, is there any progress in controlling this compressor?
I’m searching information about setting up ch-r compressor(esb20c), because for once, compressor(and bracket) for my car is made from unobtanium, second, with working stand alone controller, many people can adapt ac to cars that in never came with it, or with placement issues.
So im looking to adapt it to normal 12v car, can anyone can help me with it?
I’m searching information about setting up ch-r compressor(esb20c), because for once, compressor(and bracket) for my car is made from unobtanium, second, with working stand alone controller, many people can adapt ac to cars that in never came with it, or with placement issues.
So im looking to adapt it to normal 12v car, can anyone can help me with it?
Re: Denso ES27C AC Compressor control (Toyota/Lexus)
Siema Dziku,
As you can read from this post there are two types of this compressors .. one "ES" that is controlled via some proprietary DENSO interface ( whis is partially discovered as you can read in previous posts ), and the newer ones "ESB" that uses LIN interface.
Some hacking is needend for LIN .. i have no time to try that offline, and no acces to real car to sniff.
For planing to use that in some car with 12V supply it is useless - just imagine power requirement .. assume for about 2kW power -> about 170Amps @ 12VDC that is tremendous amount od power/current for 12V circuit, For these comressors you need about 200VDC,- So olny for EV's, hybrids, Stationary.
As you can read from this post there are two types of this compressors .. one "ES" that is controlled via some proprietary DENSO interface ( whis is partially discovered as you can read in previous posts ), and the newer ones "ESB" that uses LIN interface.
Some hacking is needend for LIN .. i have no time to try that offline, and no acces to real car to sniff.
For planing to use that in some car with 12V supply it is useless - just imagine power requirement .. assume for about 2kW power -> about 170Amps @ 12VDC that is tremendous amount od power/current for 12V circuit, For these comressors you need about 200VDC,- So olny for EV's, hybrids, Stationary.
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Re: Denso ES27C AC Compressor control (Toyota/Lexus)
I have been reading this thread with great interest, but was hoping someone could maybe help me put some information together.
I have a Lexus CT 200h (2011) that has had issues with the A/C compressor (ES27C).
I've gone through a great deal of troubleshooting and using the service manual and have eventually landed on the conclusion that the compressor needs to be replaced.
Before I pull the trigger though, one thing has been bothering me.
The fault I get on the car is B1473, indicating issues with the start-up signal (Which I believe is supposed to be STBI (pin 4, white wire) on the compressor side.
As per the service manual I have measured the wire resistance to the power management control ECU and to ground and all is within spec (below 1 Ohm between the power management ECU and the AC compressor, and above 10 kOhm between power management ECU cable to body ground) which presumably should mean that the wire harness is fine.
When measuring voltage however, I am getting a failure.
According to the manual, with the compressor connector connected, and the power management Control ECU disconnected, measuring the STB pin on the power ECU side of the cable I should be getting below 1V when the car is off (which passes, I get 0.05V), but with the ignition on I should be seeing 11 to 14V, where I am seeing 0.9V
The thing that bothers me is the fact that If I have the car running, and while it is running disconnect the AC compressor cable and reconnect it back, the compressor springs into action and the error code goes away! The AC works perfectly fine up until I turn the car off and back on again, which once again reintroduces B1473.
For some added context, when I first took off the connector I found corrosion on the connector, on pins 2 and 3 (yellow and red, DIN and DOUT).
I have cleaned up the corrosion on the AC inverter side and replaced the connector on the harness, however nothing has changed and the issue persists.
Can anyone make sense of what I am seeing? Is replacing the AC compressor the right call here?
My only real guess is that maybe the circuitry inside of the compressor got somehow messed up because of the corrosion, however its still a little odd considering the corrosion ive had was on the data lines, not the start up pin that is supposedly causing the fault...
I have a Lexus CT 200h (2011) that has had issues with the A/C compressor (ES27C).
I've gone through a great deal of troubleshooting and using the service manual and have eventually landed on the conclusion that the compressor needs to be replaced.
Before I pull the trigger though, one thing has been bothering me.
The fault I get on the car is B1473, indicating issues with the start-up signal (Which I believe is supposed to be STBI (pin 4, white wire) on the compressor side.
As per the service manual I have measured the wire resistance to the power management control ECU and to ground and all is within spec (below 1 Ohm between the power management ECU and the AC compressor, and above 10 kOhm between power management ECU cable to body ground) which presumably should mean that the wire harness is fine.
When measuring voltage however, I am getting a failure.
According to the manual, with the compressor connector connected, and the power management Control ECU disconnected, measuring the STB pin on the power ECU side of the cable I should be getting below 1V when the car is off (which passes, I get 0.05V), but with the ignition on I should be seeing 11 to 14V, where I am seeing 0.9V
The thing that bothers me is the fact that If I have the car running, and while it is running disconnect the AC compressor cable and reconnect it back, the compressor springs into action and the error code goes away! The AC works perfectly fine up until I turn the car off and back on again, which once again reintroduces B1473.
For some added context, when I first took off the connector I found corrosion on the connector, on pins 2 and 3 (yellow and red, DIN and DOUT).
I have cleaned up the corrosion on the AC inverter side and replaced the connector on the harness, however nothing has changed and the issue persists.
Can anyone make sense of what I am seeing? Is replacing the AC compressor the right call here?
My only real guess is that maybe the circuitry inside of the compressor got somehow messed up because of the corrosion, however its still a little odd considering the corrosion ive had was on the data lines, not the start up pin that is supposedly causing the fault...