Wideband controller power wiring

[hiltonlo05]

Just got in my two Spartan 2 wideband controllers from 14point7 and wanted to know the preferred way to wire the power supply.

The O2s need 7.5w each for heaters plus whatever the control circuitry requires, I would assume total load each controller would be 1-1.5 amps.

My first thought is to pull them from my fuel pump relay, it's a beefy 30amp mini relay, as long as there's no issue with that being a noisy source.

Option two would be to pull them from the ms3 ecm relay which is a 20 amp mini fed by a 3amp fuse, would need to resize that fuse to 5 or 7.5 amps. As long as that's not an issue sharing power with the ecm.

Option three...the most work, adding an additional relay to my Power Distribution Module that is controlled by the ecm relay and having the controllers on a dedicated fused relay.

Also have my 8 injectors on a dedicated relay, and 4 d585 coils on a relay and another 4 coils on another one, all 20 amp relays with various appropriate sized fuses...if any of those are an option.

Am I overthinking all of this??? I'm a stickler for the details and like to do things right the first time.

Thanks in advance!

[nathaninwa]

I think you over did the coils. I'm all for separating each system, but all my LS installs use a single 30 amp relay with 20 amp fuse for all 8 coils

Combine those and wire the widebands to the freed up relay

[hiltonlo05]

I think you over did the coils. I'm all for separating each system, but all my LS installs use a single 30 amp relay with 20 amp fuse for all 8 coils

Combine those and wire the widebands to the freed up relay

I did overdo the coils, the way they are mounted, completely separate sides of the car, it made sense to me at the time to separate their power feeds. I suppose it would be simple enough to to combine their power feeds at the PDM and borrow the freed up relay. It would mean the wideband relay is activated by the fuel pump relay which is controlled by the ms3...any foreseeable issues with that?

[MWPau]

Running it off the fuel pump relay is a good idea.
It means it'll only be powered when the engine is running which is great for WB02 sensor life.

[dontz125]

IIRC, the heaters pull ~ 3A on warm-up, 1A while running at temperature. Slightly more than 7.5W ...

[hiltonlo05]

IIRC, the heaters pull ~ 3A on warm-up, 1A while running at temperature. Slightly more than 7.5W ...

I may have misread that 7.5w spec...but either way they should be safe on a 7.5 amp fuse with a relay