Switched 12v for wideband

[m1tch]

Hi all,

Just wondering where best to tap into a switched 12v source for my wideband, I need to get a 5a fuse to run inline with the 12v feed so I am thinking perhaps take the 12v feed and ground from the radio which should be fused anyway (there isn't a radio in the car anymore). Am I correct to say that I should crimp the wires together and no solder them?

It looks like fuse 28 is for the radio and electric aerial but at 15A - I don't have either in the car so could I simply run a 5a fuse in there as specified by AEM and use that? Need to check if the 12V socket is also using the same fuse though as I will be needing that for power on a display I will be running.

Looking at the wiring diagram the O2 sensor plugs directly into the back of the gauge - was expecting there to be an additional box somewhere that the gauge plugged into but it seems to do it all in one these days!

Just wondering what others have used with their setup.

[m1tch]

Can anyone help me on this, I have passed the wires through the fire wall so its ready to connect up, I am thinking I can just use the radio harness for the power but have read that I should use a common ground to the ECU - is this correct? If so which wires do I need to attach the +ve and -ve to?

[jvanzyl]

Hey - best place is behind the clock. You'll find all you need there.. have a look at some of my threads where I was wiring in my EDFC for the diagram etc...

[m1tch]

Hey - best place is behind the clock. You'll find all you need there.. have a look at some of my threads where I was wiring in my EDFC for the diagram etc...

Hmm my issue is that I think the wideband needs to have a common ground with the ECU to make sure it gives a correct signal - I have no radio so I can easily connect it up to that as there must be a switched 12v somewhere in that wiring but wasn't sure if it would cause an issue with having a different ground.

[jvanzyl]

Well you could run the ground from the ECU under the middle console to behind the clock if you really wanted to... but it couldn't hurt to try the connections behind the clock as they are pretty well situated...

The clock has 4 wires coming out of it.
Grey - approx 12V with ignition turned on
Red - always on at approx 12V
Green - approx 12V with light control on sidelights or main beam
White/Black - ground

[m1tch]

Well you could run the ground from the ECU under the middle console to behind the clock if you really wanted to... but it couldn't hurt to try the connections behind the clock as they are pretty well situated...

The clock has 4 wires coming out of it.
Grey - approx 12V with ignition turned on
Red - always on at approx 12V
Green - approx 12V with light control on sidelights or main beam
White/Black - ground

Thanks for that, will take a look - is it hard to get behind the clock?

[jvanzyl]

No worries and Nope! (This is why I went for it).

1 - Take the knobs off of the heater controls and the interior recirculation slider
2 - There may be a couple of screws to now undo, if not just pull the fascia directly off now
3 - I think the clock should just be there for you to unplug and then splice into the wires...

It's very easy to get to..

[m1tch]

No worries and Nope! (This is why I went for it).

1 - Take the knobs off of the heater controls and the interior recirculation slider
2 - There may be a couple of screws to now undo, if not just pull the fascia directly off now
3 - I think the clock should just be there for you to unplug and then splice into the wires...

It's very easy to get to..

Perfect, will check tonight  s:) s:)

[m1tch]

I am going to use the stock radio loom and after using a multi meter I have found the switched 12v and a ground - seems that the ground is actually at 0.5v but it works perfectly for the gauge, just need to secure the wideband O2 wiring in the engine bay - have fitted the sensor in one of the OEM locations as its a perfect fit.

I haven't fully wired it in as I have found that simply pushing the wires into the stock connector block holds them in quite tightly - will solder them properly once its working and I have routed all the wires around.

[alancsalt]

I have a live from the battery going through a relay activated by the ignition. It has a fusible link at the battery end.

[SteveJ]

If you're going to use the wideband to drive the ECU narrowband inputs a ground of 0.5v means you'll never cross the switching point as far as the ECU is concerned.

[Essex2Visuvesi]

Might be a good idea to have a chat with Carolyn.... I beleive she had issues wiring in her Wideband

[m1tch]

The PFC ignores the OEM O2 sensors I think, I have it all connected up temporarily to check that its working, will be plugging in the Hako very soon but its looking good so far!

[m1tch]

Looks like my switched 12v source using the radio is only a 12v source until you turn the headlights on! Will look to take the front of the dash off to get to the clock 12v supply as it should be more consistent - really do hate wiring! The Copilot also isn't picking up the voltage from the wideband either, its just stuck at the default 14.2 and doesn't move  s:( s:(

[alancsalt]

I could be wrong, but my understanding ATM is that the PFC does use the stock narrowband O2 sensor, and that you cannot just switch that out for a wideband sensor for day to day running, (because the PFC is not designed to read wideband) but if you have a datalogit or hako or similar, you can use the wideband to tune the car. My PFC is hooked up to my stock narrowband sensor, and my wideband just runs an AFR gauge. My dyno tuner says his equipment is better anyway, and he doesn't use my wideband sensor.

 m http://www.innovatemotorsports.com/reso ... torial.php m

[jvanzyl]

Looks like my switched 12v source using the radio is only a 12v source until you turn the headlights on! Will look to take the front of the dash off to get to the clock 12v supply as it should be more consistent - really do hate wiring! The Copilot also isn't picking up the voltage from the wideband either, its just stuck at the default 14.2 and doesn't move  s:( s:(

I knew you'd return to it  s;-) ;-) s;-)  it's just so much easier!