2009 Chevy Aveo5 - error code P0641 (Update - FIXED - damaged connector)

[Enjoyneering]

Good day everyone,

Does anybody have electric schematic for 2009 Chevy Aveo5? Looking for how many sensor are connected to MCU +5v ref. line?

Thank you.

P.S car runs fine, just check light (for now) and permanent code P0641.

[Enjoyneering]

Good day everyone,


I was too confident saying - "car runs fine". The P0641 slowly drained my battery from 12.7 volt to 7 volt in a week.
The good news, I found schematic & localized the issue. The voltage on exhaust camshaft position sensor, intake camshaft position sensor and fuel tank pressure sensor is too high - 11.9v. Checked the wires from ECM to each sensor - no short circuits. Any suggestions?

Thank you.

[petrified.rabbit]

Often this is a source issue more than a draw issue (IE. computer). But disconnect each of those sensors one at a time and check for a voltage drop. I don't have the schematic, but is the too high-11.9v coming from diagnosis or the scanner? is it a good scanner? Often that code can mean one of the 3 sensors doesn't have a signal, and only a sensor needs replaced. You can check each of them for an open circuit.

If you have a drain on the battery, it might not be related to that circuit, unless another system has shorted into that harness and is providing the 12v source. Im not sure where to tell you to check this, either in the ECU, or fusebox perhaps?

If your car is a manual, low optioned car, I have a spare ECU I could send you to try. But any potential ECU coding issues would need sent to dealership anyhow.

[Enjoyneering]

Hi,

Thank you for reply. I'm not a mechanic to buy an expensive scanner. All I have is "poor man" OBD ELM327 v1.5 bluetooth adapter. I used voltmeter and done my homework about P0641 troubleshooting.

After the all sensor were disconnected, the voltage on each 5v pin was 11.9..12.7v. It's obviously a short circuit between 5v ref. and line connected directly to the positive battery terminal.

P.S. Do not agree with - "Often that code can mean one of the 3 sensors doesn't have a signal". ODB2 protocol has different codes if the sensor doesn't sent the signal. For example P0363 or P0340 or P0341 and ect.

[Enjoyneering]

Good news everyone.

After a week of troubleshooting I found the problem. It wasn't a short circuit, just a bad connector. This is why it took so long.



Also my problem with LTFT and STFT (described here http://www.aveoforum.com/forum/f81/o...85/index3.html) is gone too. Now I have nice 0..3% long term fuel trim +-5% short term fuel trim anytime.

[xintersecty]

That looks like the main cable going to the firewall into the cabin. Yech. Any ideas on how you are going to fix it?

[Enjoyneering]

First pin in the second row disappeared. I've put the wire through, see sketch below. Still able connect/disconnect it, except one wire.

[Mwbrown93]

What connector is that And where is it located? I have the same problem

[Redber1980]

I want to know too