Hope everybody had a great weekend. I am new to this forum and new to forums in general. I've searched through this forum for answers to my problem, no luck yet.
So here's what's going on. I have a 2005 Lexus LX 470 that I purchased about a month and a half ago, it did not run at the time due to timing belt breaking but that is all replaced and repaired. The vehicle now runs great.
I'm quite mechanically inclined. I've built several engines and tuned them myself.
I'm getting 4 consistent codes, all are the same. "heater control circuit low'' from all of my O2 sensors.
I have replaced all of the O2 sensors with OEM ( Denso ). And the codes are still there.
I have measured the voltage and the voltage is reading low.. 0.04v. It should be around 12v with the key on (and running).
First conclusion is that I have a short in the system… I have checked absolutely everywhere. I nearly pulled the whole harness out. The wires look super clean and I don't think that's my issue. I have even unplugged the three connectors on top of the transmission just to make sure nothing back there was interfering. With the three plugs disconnected, the problem still persist.
I have checked all of my grounds and have personally taken them loose, sanded them down and re-connected them.
I have a nice OBD2 scanner with live data and I can see signal coming from the O2 sensors, which is great. But the voltage is still low, which throws the code.
I also have an issue with my evap purge valve. The valve is good. I've tested it but when using the scanner to turn on the purge valve, I cannot activate it. I can activate the pressure relief valve that is closer to the driver side fender.
This leads to the gas tank not being able to bleed of pressure. You can smell it when the car has been running for a while.
I feel like whatever is disrupting my O2 sensors is also affecting my purge valve.
Would anybody here happen to have an ECU pin out diagram for a 2005 LX 470? I would like to measure the voltage coming out of the ecu.
Has any of you experienced anything like this? Any advice you would like to give?
Anything would be greatly appreciated. Thanks in advance!
So here's what's going on. I have a 2005 Lexus LX 470 that I purchased about a month and a half ago, it did not run at the time due to timing belt breaking but that is all replaced and repaired. The vehicle now runs great.
I'm quite mechanically inclined. I've built several engines and tuned them myself.
I'm getting 4 consistent codes, all are the same. "heater control circuit low'' from all of my O2 sensors.
I have replaced all of the O2 sensors with OEM ( Denso ). And the codes are still there.
I have measured the voltage and the voltage is reading low.. 0.04v. It should be around 12v with the key on (and running).
First conclusion is that I have a short in the system… I have checked absolutely everywhere. I nearly pulled the whole harness out. The wires look super clean and I don't think that's my issue. I have even unplugged the three connectors on top of the transmission just to make sure nothing back there was interfering. With the three plugs disconnected, the problem still persist.
I have checked all of my grounds and have personally taken them loose, sanded them down and re-connected them.
I have a nice OBD2 scanner with live data and I can see signal coming from the O2 sensors, which is great. But the voltage is still low, which throws the code.
I also have an issue with my evap purge valve. The valve is good. I've tested it but when using the scanner to turn on the purge valve, I cannot activate it. I can activate the pressure relief valve that is closer to the driver side fender.
This leads to the gas tank not being able to bleed of pressure. You can smell it when the car has been running for a while.
I feel like whatever is disrupting my O2 sensors is also affecting my purge valve.
Would anybody here happen to have an ECU pin out diagram for a 2005 LX 470? I would like to measure the voltage coming out of the ecu.
Has any of you experienced anything like this? Any advice you would like to give?
Anything would be greatly appreciated. Thanks in advance!
