MrGorsky

Well-Known Member

Full Member

• Thursday at 19:36

• #1

Evening All,

Whist doing some diagnostics on my GEMS 4.6, I notice I have an error code 1190 Oxygen Sensor Heater Circuit Low Resistance. Can't find much about it with Googling, but is this probably a defective O2 sensor? I don't have a MIL light or anything. The engine is running sweet as anything. I suppose I could get under and measure the resistance of the O2 sensor wires.... once I've worked out which ones they are!

I replaced them both only a couple of years ago, so I'd be annoyed if they're bad already.

 

pwood999

Well-Known Member

Full Member

• Thursday at 19:49

• #2

Are the Sensor voltages going up & down ? Could also be the sensor connectors either side of the block. They do tend to gather oil down there.

 

MrGorsky

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• Thursday at 20:04

• #3

They are. Up and down 5 volts down to 1 volt near enough.

 

Mark Piercy

Well fumbled member....

Full Member

• Yesterday at 10:07

• #4

How many wires are on the sensor in question? It sounds like just the heater side has failed, if they a four wire.

 

MrGorsky

Well-Known Member

Full Member

• Yesterday at 10:09

• #5

I think they are. Pretty crap to fail after maybe only one year. I’ll have to get the multi meter on it.

Could be a broken wire I suppose. The wires are much older than 1 year!!

 

MrGorsky

Well-Known Member

Full Member

• Yesterday at 10:37

• #6

Just been and tested again, the fault has gone. Maybe it's a dirty connector or something simple.... I'm hoping that!

 

Mark Piercy

Well fumbled member....

Full Member

• Yesterday at 16:01

• #7

The heater only heats the sensor but doesn't effect it's functioning on a warm engine when it switches off the heater side of the sensor.

 

pwood999

Well-Known Member

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• Yesterday at 17:08

• #8

BTW, UK cars generally don't light the MIL like the US versions do. Definitely check the sensor connectors either side of the block first, and measure the resistance. Could also be the connector on the GEMS ECU, but that's less likely.

 

P

Pug957

Active Member

• Yesterday at 18:15

• #9

Low resistance is normally the heater coil inside the sensor fusing together. Very very rarely wiring or connector issues. New sensor of the correct specification should sort that code, and as said earlier, will function fine once warmed up by the exhaust gasses.