Brainteaser for you electrical engineers, et al!!
My relay for my O2 sensor heater is not operating properly. I have no voltage at the sensor. I can hear the appropriate relay clicking under the hood, but it doesn't seem to be switching the current right because if i bridge the circuit with a piece of wire, i get +12 at the O2 sensor, but otherwise i get nothing. I swapped out a couple of different relays (eg horn & defrost) but that didn't do anything. I'm absolutely stumped as to what is happening, why i can get current to the sensor if i bridge the circuit, but i cant get current to the sensor with the relays. Does anyone have any ideas?
Are you bridging the correct wires? Has any of >>
the wiring been messed with before?
Pop the cover off the relay and observe it's action.
Depends on the construction of the relay>>>
It's just a box, be it metal or plastic. I guess it depends on your skill :o)
Re: Brainteaser for you electrical engineers, et a
Are you checking with the engine running or just key on? Fuel pump relay controls power circuit for O2 relay, so it'll only trigger when engine is running. IIRC