Rocketman69, look in here for LS2 GTO HO2S connections...

[joecar]

Gib,

I couldn't attach files to the pm I sent you, so here are those attachments...

This is for 2005 GTO.

The HO2S plug is a little different, it has 2 keyways on it, see the pic.




Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1

Connector Part Information		• 9723-6897-40 • 4-Way F (GY)
Pin	Wire Color	Circuit No.	Function
A	BU/BK	1664	HO2S Low Signal Bank 1 Sensor 1
B	PU	1665	HO2S High Signal Bank 1 Sensor 1
C	BK/WH	1050	HO2S Bank 1 Sensor 1 Heater Low Control
D	PK	439	Ignition 1 Voltage

[joecar]

Gib,

You may not be able to power your LC-1 from the HO2S connectors because the PCM controls the heater power, as you can see in the wire diagram;

maybe the PCM switches heater power on and keeps it on, I don't really know... you could test that with a DMM, and if id does keep the heater power on, then you should be ok.

Cheers
Joe

[Rocketman69]

Thanks Joe! That's exactly what I've been looking for.

[Rocketman69]

Gib,

You may not be able to power your LC-1 from the HO2S connectors because the PCM controls the heater power, as you can see in the wire diagram;

So what controls the heater power on the LS1 cars?

[joecar]

So what controls the heater power on the LS1 cars?

On F-body LS1, it is controlled by the ignition relay via the ENG SENSOR fuse, so it's direct.

[Rocketman69]

ah....I see. So the heater circuit on the LS1 cars isn't monitored by the PCM at all....I believe we get a code if the heater circuit doesn't read any voltage at the PCM.

[joecar]

ah....I see. So the heater circuit on the LS1 cars isn't monitored by the PCM at all....I believe we get a code if the heater circuit doesn't read any voltage at the PCM.

That leads me to believe the PCM possibly just keeps heater power on all the time (and why wouldn't it, it wants feedback from the O2 sensors).

[Gelf VXR]

Gib,

You may not be able to power your LC-1 from the HO2S connectors because the PCM controls the heater power, as you can see in the wire diagram;

maybe the PCM switches heater power on and keeps it on, I don't really know... you could test that with a DMM, and if id does keep the heater power on, then you should be ok.

Cheers
Joe

Hi Joe, another post from the dead, how about this possible issue, was it resolved? How would the PCM control the heater power thru the ground wire?

[joecar]

Hi Joe, another post from the dead, how about this possible issue, was it resolved? How would the PCM control the heater power thru the ground wire?

Hi Gelf,

The 4th Gen F-cars powered the NBO2 heater via a relay that come on with key on, and the heater ground goes directly to chassis/battery ground... so trying to power a wideband from here is not a problem (as long as all the wiring and terminal crimps are in good condition, i.e. no voltage drops).

The GTOs on the other hand have the NBO2 heater ground going to the PCM, and we found that the PCM controls heater current/temperature by doing PWM on the heater ground... so trying to power a wideband from the NBO2 connector does not work due to repeated interruption of ground.

[Gelf VXR]

I have a vauxhall monaro, similar/same E40 PCM as the GTO. Ive had the LC-1's wire to the PCM heater and ground since day one, the LC-1s seemed to work fine, never reported any errors, but im sure the grounds must have affected the response and accuracy.