Not knowing what engine you have in that 02 Dodge, the bank of cylinders on a V6 or V8 that contains the #1 cylinder is bank 1. Sensor 1 would be the first sensor threaded into the exhaust system after that bank.
Assuming you mean P0135, that would be O2 sensor heater circuit malfunction (bank 1 sensor 1). If the wiring to bank 1 sensor 1 is not damaged, it is probably a bad bank 1 sensor 1 O2 sensor. Replace it.
where is the bank 1/sensor 2 O2 sensor on a dodge caravan...to the rear of the catalitic converter or to the engine (front) side of the converter?
There are three 02 sensors. The front left sensor is the forward most sensor, on the left bank of the engine. The next is the front right sensor on the right bank, the rear sensor is after the catalytic convertor. see below web site: http://www.courtesyparts.com/A32_O2-sensors.html
P0137 = O2 sensor circuit low volts (bank 1 sensor 2). Could be a faulty B1 S2 O2 sensor.
Bank 1 is the bank next to the radiator. Sensor 1 is screwed into the exhaust manifold.
On a 2006 Dodge Dakota bank 1 sensor 1 is driver side above the catalytic converter.
Bank 1 is the driver side.
That is the O2 sensor behind the catalytic converter.
02 sensor circuit slow response bank (bank 1 sensor 1)
Bank two sensor two on a 2002 Ram is passenger side, after the catalyst.
Bank 1 would be the bank of cylinders that contain cylinder number 1. Bank 1 on the 3.9 would be the bank of cylinders located on the drivers side of the engine. Bank 1 sensor 2 would be the O2 sensor located after the catalytic converter.
Bank 1 is the pass side.
Sensor 2 is allways further down the pipes. It is allways after the Cats Are your cats Missing and is this setting the code? Bank one is the driver side. Sensor two will be the sensor either in or below the small cat close to the engine.
Trouble code P0161 means:O2 sensor heater circuit malfunction (Bank 2 Sensor 2)
O2 sensor circuit low voltage (bank 2 sensor 1)
Trouble code P0546 means:Exhaust gas temperature sensor circuit high (bank 1)
It actually screws into the middle of the cat.