Originally Posted by Thermo

HELP, first things first, take a look at your multimeter and make sure you you are first on the correct scale. If you look at the dial, you should see something that looks like an omega (aka, an O that has feet). Some multimeters may have a number of scales that will read out as say 2M, 200K, 20K, and 2K. If this is what you have, then you want your multimeter on the lowest scale. Either one works. Next, check to make sure that your multimeter does not have the MIN/MAX function turned on. that can goof up a lot of people (even me who works with them every day). The final thing is to do the check that you did in that you should see your multimeter show a very low number when you touch the leads together (in your case you saw 0.6) and when you pull the leads apart, it should say "OL" (possibly something like "MAX"). Now, when you touch the leads of the O2 sensor, you should see it go from OL to a low value (as you touch the wires to the leads) and then when you disconnect the leads, jump back up to a high value. If you see your multimeter stay at "OL" the whole time, then the heater circuit is bad and you need a new O2 sensor (does not appear to be your case). If you are seeing the multimeter go from OL to a low value, then to some other value, you have something turned on wtih the multimeter and we need to figure out what it is so we can ensure we are getting accurate readings.

Originally Posted by h2o2steam

Your meter shows a "1" to the left of display when it is not measuring any resistance.
When you touch the probes together the meter cycles through obtaining a measurement and quickly settles on 0.5ohms.
As said before, that is the meter's interpretation of the resistance of the meter probes. In a perfect world you should get a resistance of 0.0 ohms and holding the probes together for an extended period of time the meter might auto calibrate, but for your purposes 0.5 ohms is just fine for your "zero or short circuit" resistance.

You then set about to measure the heater circuit of the O2 sensor and you get no resistance reading (just showing a "1" on the meter's left side of the display.
That is a failed sensor heater as you should be getting a measurement of probably 1 to 2 ohms showing on your meter.
If you like, unplug the downstream sensor plug and measure that......I would expect you will get a low resistance reading of a couple of ohms on the two black wires of that sensor.

Originally Posted by Thermo

HELP, ok, like what H2O2 said, when you have your probes apart and the "1" shows up, that is how it is saying that it is seeing a resistance greater than the selected scale. Never seen a multimeter do that before, but, it makes sense in a weird way.

So, you have a bad heater in that O2 sensor and that is causing it to read erroneously and therefore needs to be replaced. If you look next to where you unplugged the upstream sensor (that had a grey plug), you will see a black plug. that is the downstream sensor. It plugs into the center of the catalytic converter there dead center of the engine, under the air box. You look down there, you will see it sticking out the side. But, really, you just need to get access to the plug which is out in the open. Repeat the same steps like you did on this sensor and you will see the difference. What was confusing me was you were saying that you were getting 1 (which I assumed to be 1 ohm), but in reality, it was your meter saying that the resistance is greater than 200 ohms (aka, heater is bad). This is why a lot of meter say "OL" (overload). This way it doesn't get confused with an actual reading or something of the like.

Originally Posted by h2o2steam

P1000 code is nothing to worry about.
The car internally tests itself to check off emissions, evaporation system performance etc. so it displays a P1000 code until it has successfully worked through and ticked off all of its internal checklist.

Originally Posted by Thermo

Help, you have 2 ways to clear the check engine light/get rid of the P1000 code. The quickest way is to simply disconnect the battery after you do the repair to clear the memory of the ECU.