Power Source for WB02

[VetPet]

I'll be getting my LM 1 soon (thanks IRA) and was just wondering if there's a preferred place to get the 5V feed for the O2 sensor? If I've understood correctly, you want there to be power to the sensor when the key is in the 'on' position in order to heat up the 02 before starting the car. This will help the 02 have a longer lifespan. Suggestions would be appreciated.

:cheers:

[Bruce Melton]

Are you mounting it permenently and using a single purpose sensor for the WB or other?

[m396 #00-011]

The LM-1 needs 12v, not 5v. It send the 5v out of the LM-1 to the sensor itself. If this is for a C5, use the Aux power in the passenger side fuse box. It's behind the floor mat and a little door in the footwell. There is are black, orange and red wires under there, I believe. Black is ground, and the two others are switched and constant power. Use a multimeter to test which one is which.

[caver]

I put a cigarette lighter plug on mine and just plug into the lighter or powerpoint.

[VetPet]

:thankyou2: Took a better look at the LM-1 instructions. It comes with a power cord to plug into the cigarette lighter for 12V power. Since I don't plan on permanently installing the WB this will be my power source for it. However, if I decide to leave it mounted in the exhaust I'll have to find a switched 5V source to keep it heated when I'm not using it for tuning. What's a good place to get power if I decide to go this route?

:cheers:

[Bruce Melton]

:thankyou2: Took a better look at the LM-1 instructions. It comes with a power cord to plug into the cigarette lighter for 12V power. Since I don't plan on permanently installing the WB this will be my power source for it. However, if I decide to leave it mounted in the exhaust I'll have to find a switched 5V source to keep it heated when I'm not using it for tuning. What's a good place to get power if I decide to go this route?

:cheers:
Not to avoid your question but first I suspect you will not want to run it when not tuning as you will need that extra bung and will need to keep it hooked up to 12V. The 5 volts really only comes into play if you want the WB sensor to also output to the PCM thus replacing the OEM and becoming dual purpose. That setup has not has not worked well for most folks.

[joecar]

Need a switched 12V source (as in NBO2 harness connector pin D).

If you are not tuning, you still need 12V otherwise WBO2 sensor will be damaged
(there's discussion regarding this at the Innovate forum).

[VetPet]

I'll be installing a bung for the WB sensor to keep it separate from the NB02. I didn't want to install the WB permanently but it might be better to do so for a while during my initial tuning period so I don't have to keep getting under the car to install it.

It sounds like I can tap into the 12V supply to the NB02 so that my WB will get power to keep it heated. As noted by Joecar, if you don't do this you will greatly reduce the life expectancy of the WB02.

I don't think I'll try to get the WB02 to output to the PCM and act as a NB. Bruce you've alluded to the problem being encountered by others trying to do this and I don't want to complicate the process any more than I have to. Remember the KISS rule. Keep It Simple Stupid! Words to live by.

:cheers: :beer:

[SSbaby]

:thankyou2: Took a better look at the LM-1 instructions. It comes with a power cord to plug into the cigarette lighter for 12V power. Since I don't plan on permanently installing the WB this will be my power source for it. However, if I decide to leave it mounted in the exhaust I'll have to find a switched 5V source to keep it heated when I'm not using it for tuning. What's a good place to get power if I decide to go this route?

:cheers:
Also a hint to make sure you power the LM-1 unit up everytime you start your engine otherwise it could lead to premature WO2 failure.

That's why a lot of people have purchased the simpler (and cheaper) LC-1 unit as it must be wired to a switchable 12V source... it kind of eliminates the often forgetful task of you having to remember to turn your LM-1 on.

EDIT: didn't read Joecar's same message. :exactly:

[joecar]

a. If you're running the WBO2 in place of the NBO2, you can install a square HO2 plug on the end of the LC-1/LM-1 so it can be connected to the vehicle harness (heater power/ground and optionally NB signal high/low).

b. If you're running the WBO2 in its own bung, you can fab up a Y adapter (one plug to two sockets) to connect both the NBO2 and the LC1/LM-1 (heater power/ground only) to the vehicle harness;
I haven't tried this so I don't know how much current it draws.

Edit: Or, if running b., do a. but plug it into one of the rear HO2 sockets.

:beer:

[VetPet]

Sounds like I'm gonna need a schematic. I think you could calculate the current draw if you know what the sensor resistance is (Ohm's Law I=E/R) as by splicing into the existing harness you've created a parallel circuit to the NB02. The same applies if you use the rear H02 as your power tap. I'm hoping to get a hold of the service manual soon.

:thankyou2: